Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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The reason i call this an assembly and not an ATM is because i am not polishing my own lens, making a lens cell, or fabricating a focuser. I am just assembling parts that i have ordered, i will post this so i can get some input and ideas from others to help me, and in return maybe i can help another refractor build in the makings.
I purchased a 127mm f/5.5 from Surplus Shed. It is air-spaced achromatic optics, fully coated, 127mm diameter with a focal length of 700mm. The entire lens housing is 130mm long and made of thermo-plastic. The coating are nice and it is a big son of a gun, i am sure from the price it will show its share of false color and have so softness on the edge but for the price it should be a fun scope, i am not expecting much. It will be used at low power as a Milky Way Buster and Satellite finder so color won't bother me. I purchased a 5" OD aluminum tube from a local supply store it is very nice and has good roundness. The focuser and adaptor plate were a scope stuff buy, the adaptor is the Adaptor Ring for Crayford Refractor Focuser on 5.125" OD Tubes. And since my OD of my tube is 5" and the adaptor is for an 5.125" i know i will have to do some magic to make it fit(later).
I figured out the size of the tube by making a "scope on a stick" and focused on some stars. I mounted the lens/cell on a board and mounted the focuser and adaptor behind it on an adjustable sliding jig. I used three eyepieces a 30mm, 12.5mm, and a 5mm along with a diagonal, starting out in the mid range of the focuser with the 12.5mm first. Then making sure i found the optimum position of the focuser using all the eyepieces, i marked its position on the board. That will be a rough tube length.(sorry no pictures of the scope on a stick due to the juggling act of making sure nothing came crashing to the ground).
Once i determined my tube length i cut the tube. Cutting aluminum tubing can be tricky and dangerous(aluminum tubing can fly around if the saw teeth grab instead of cut) so i borrowed my brother's metal chop saw. It did a great job, here is a picture of the metal chop saw and a different OTA i had cut.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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The cut isn't the most accurate cut but it is a safe cut(no flying OTA's). To square it up i wrapped a sheet of paper around the tube tightly so that the top edges of the paper met ensuring a straight edge. This let me see which areas were high and needed to be filed down. I sprayed black spray paint(leaving the paper ledger in place) to blacken and show the high spots when the paper was removed.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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now all that i had to do was file the blacken high areas and i had a square even tube.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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Now some easier stuff like mounting the lens cell. First i removed all the glass as so not to have any mishaps. I want to get it as square as possible but i am going to have to rely on the manufactures accuracy on this one due to the fact that the tube slides fairly deep into the cell so the is no play to collimate.
I slid the cell in place and marked the three holes,removed the cell, and drilled the holes using a drill press. I made a simple jig to get the holes straight.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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Since my tube is fairly thick i tapped the holes so i wouldn't have any nuts or washers inside the tube(less light scatter). Excuse my dried out dirty hands, earlier this morning i was using some strong degreasing solvent on my lawnmower engine, i was getting it prep'd to winterize.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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Then i worked on the other end of the tube. First i removed the lens cell for ease of work. And i had to conquer the problem of the adaptor being 5.125" inside diameter and the tube being 5" outside diameter. I had some scrap aluminum of the perfect thickness laying around so i cut it into a 0.75" strip and bent it around the tube by hand to give it some memory.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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I cut it to size and filed all the burrs off. Then i fit it into the adaptor plate. The adaptor plate is black and the aluminum filler strip is obviously silver. I marked each hole so when i disassemble it later i know exactly which way the strip,adaptor, and tube holes align.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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It is late so i am calling it quits. I still have to mount the adaptor and collimate the focuser. I need to find out from some of you ATM'rs how to do a "ray trace" for knife edge baffles???? Mount finder scope, paint inside and out, make some rings(i have a good idea for those), and also a good idea for a dewshield.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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 mattyfatz
Pooh-Bah
Reged: 12/27/06
Posts: 1293
Loc: Boise Idaho
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Looks good so far. I'm glad you had the "perfect piece" of scrap aluminum in your shop. I never do. As for the "ray Trace" its kind of hard to explain without pictures. I can send you some pages from SAM BROWNS ALL ABOUT TELESCOPES that describe it pretty well. PM me your email and fax if you can.
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**Matty**
Stimulating the economy, one piece of equipment at a time.   
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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Thanks Matty but i have been searching through the archives and i think i may have it, with the exception of one hang up. If you look HERE How do i select a desired size for the illuminated field and draw it at the focal plane? I am keeping in mind i will probably be mostly using a 30mm Tele Vue plossl, or a 26mm Meade smooth sided Super Plossl.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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Since i was at a bit of a road block with the ray tracing, i decided to paint some shiny surfaces with Ultra Black Krylon paint. These are surfaces that may reflect and bounce light around in the tube, some may think it is overkill but it can't hurt being safe. The red arrows show the surfaces painted, masking off these parts can be a bit of a pain, i hope it pays off?
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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I also scuffed and painted the retaining ring for the cell it had a sheen to it that i didn't like(it will now match the inside of the future dewshield). It still needs a second spray.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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The lens cell had that ugly brown Synta color, so i sanded it down and primed it, it will be a satin black to match the rear focuser transom.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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beanz4
member
Reged: 08/23/08
Posts: 33
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More updates please, really looking forward to see what else you have done with your scope.
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reodds
member
Reged: 05/04/06
Posts: 76
Loc: Merrick, New York
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Brian, perhaps you want to wait to complete your scope, and make the tube out of carbon fiber!
Or make this one, and use it as a template for a cf tube, whic would be a major weight saver over metal.
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Roger
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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Sorry Beanz4 i have been directing my attention to another build HERE. The baffles on the 127mm will be similar but i will need more. I need better weather to do a test run with a 32mm Meade SWA and then i can do a ray trace with those measurements. And as you can see my sky clock is white so i will just have to wait. 
Roger i was thinking of a cf tube for this project but getting a mold tube the exact size for the lens cell and focuser transom is tough. I want to see how yours comes out then i will try it with a Newt, i have a few mirrors laying around in wait. I do have some cf sleeving that i bought for the dewshield and heat shrink to match, but that was going to be later in the post, plus i want to do a cf laminate for the rings and maybe incorperate the finder into the cf mix.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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oneslowz28
Witty Title
Reged: 11/14/06
Posts: 595
Loc: Aiken , Sc
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This is coming along great. Keep up the good work.
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Charles "Jeff" Gantt
Orion XT12I
16" lightbridge f/4.5
Orion 100mm ED Apo f/9
TeleVue Bino viewer
8mm Baader Planetarium Hyperion
35mm TeleVue Panoptic
40mm pair William Optics SWAN
20mm pair William Optics SWAN
Oron Stratus 17mm
Orion shorty plus 2x barlow
Orion 2x apo 3 element 2" barlow
The C. Gantt Observatory.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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Quote:
This is coming along great. Keep up the good work.
I wish that were so. I was drawing a ray trace tonight to plan my placement of baffles and i made an alarming discovery. The drawtube is pinching the optical light path! I picked my desired field size using a 2 "32mm Meade SWA eyepiece at focus. And i set the drawtube distance at focus using a diagonal(diagonal is not drawn in)and the optical path in red is pinched dramatically by the focuser drawtube. At first i thought i could shorten the drawtube but with this GSO model it can't be shortened(internal roller bearings ride on drawtube to stabilize). I have a longer section of aluminum tube for another OTA but it wouldn't help because the focuser drawtube would still be at the same position. My only hope is using a 2.7" focuser, i do have one but it will be a pain to mount. ANY IDEAS? Are my drawings correct? I am new to this so any help would be appreciated, please excuse my drawings i am not a draftsman.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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A close up at drawtube. red is desired optical path for a 32mm 2" and green is pinched path.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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You can see with the green how little of the lens i am using. A glorified 80mm! 
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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I did some quick calculations and if i switch over to this focuser i would have a clear optical path. But it will be a headache to mount, and it would add some weight. Although i am not concerned too much with the weight because it will be mounted on a very sturdy Alt/Az. If anyone could come up with a quick fix for the use of the 2" focuser i would love to hear it? Thank you.
BTW even with the set back i am having a blast assembling this monster.  And i am learning from my mistakes. 
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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Well after going over the ray trace, talking it over with a few CN's friends,taking some more measurements,and loosing a few hairs i think this will work after all. I decided to continue the build just as it is(using the original GSO focuser) and after completion, cut the focuser drawtube to the correct length(i can safely lose a few millimeters).
So i am up to the light guards(baffles). I am putting to use some of my wife's old CD's, the Bee Gees to be exact, heck she won't miss them and besides Disco is DEAD. 
I will be using the drill press so I made a simple jig with a piece of scrap wood and tape. I drilled a 1/2" hole to match the hole in the CD, i simply line up the holes and tape the cd to the wood. I am not going to clamp the CD down because if anything grabs or binds the CD will shatter into plastic Disco shrapnel(i know from experience,i lost a few clamping them down). Now if anything should grab, the tape should give out first. So far no mishaps with the tape technique(always wear safety goggles).
Notice the bevel of the circle cutter, this is how you will cut your knife edge bevel into the plastic of the CD. I used the slowest speed on my drill press and lowered the cutter as slowly as possible, NO RUSHING trust me. 
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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Here you can see the knife edge bevel that goes towards the focuser.
BTW Krylon Ultra Flat reacts poorly to the plastic CD so a coat of Plastic friendly primer is a must then Ultra Flat can go on top of that.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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here is the other side that faces the lens, i still need a light sanding to remove any burrs and then the final coat of Flat after it is glued into the tube.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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I was lucky because it just so happens that the diameter of the CD's are almost exactly the same size as my tube inside diameter so i didn't have to cut them to size. But they are literally a hair too small but the silicon will fill in the micro-space anyway. The only trouble is how to hold them in place while drying?? I solved this by spraying a textured paint called Rustoleum "Stone Creations" into the tube first. The micro bumps not only create hundreds of mini light blocks but it also adds just enough thickness to hold the CD baffles in place while i apply the silicon. i will be using paintable silicon and apply a final coat of Flat Black to the baffles, and inner wall of the OTA. Test paint your silicon and make sure they work together ahead of time.
Before installing the baffles i will knock down the bumps with 320 grit sandpaper to remove any loose granules. Then i can install the baffles and recoat with flat paint.
Here is a photo of the first coat of textured paint, not yet flat painted.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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Before i go any further i have to start thinking and designing a mounting system and decide what type of finder to mount. It will be easier to drill and tap the tube now without the baffles in place.
I am leaning towards radius blocks like the kind found on a Cassegrain. I will be using this on an Alt/Az setup and rotating won't be necessary so that rules out rings. And since it is a RFT i was thinking of a telrad or maybe a simple 50mm finder.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Anil
member
Reged: 11/21/07
Posts: 128
Loc: Bangalore, India
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Great idea Brian, thanks!!!
I shall follow your idea of making baffles from old cd's.
I am yet to install baffles for my 4" DIY refractor
Anil
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DIY 100mm CARTON @ f/13
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dawsonian2000
professor emeritus
Reged: 07/26/06
Posts: 563
Loc: Riverview, FL, USA
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Love your idea for knife edge baffles, Brian! I will be using your design in my 127mm f/9.4 refractor. To help in secure them in the tube I will glue three blocks 120-degrees apart.
Thanks for sharing,
Mel
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Clear Skies, Forever!
The Vega Sky Center
10" (254mm) F/5.65 Home Built Fork Mounted Newtonian Reflector
5" (127mm) F/9.4 Home Built Refractor (under construction)
3.5" (90mm) F/11.1 "Vixen-Spec Modified" Konus Refractor
3.1" (80mm) F/6 Scopos ED APO Refractor
4.5" (114mm) F/8 Tasco 11te-5 Newtonian (under restoration)
2.4" (60mm) F/16.7 Tasco 7te-5 Refractor
2.4" (60mm) F/15 Jason Discoverer 313 Refractor
http://www.vega-sky-center.com
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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Thanks Anil and Mel, BTW both of you guys have incredible scopes. 
I taped off the tube and sprayed a coat of primer onto it. I am still up in the air about mountings. I like the idea of radius blocks, they are clean and out of the way.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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I have changed my mind so many times with this build but i guess that is half of the fun. I was going to buy a Telrad but i decided to get a 50mm objective from SS for an ATM finder. Heck it may as well match the SS main objective. Man oh Man....I need more projects like i need another hole in my head.  I plan on using this 2.5" diameter delivery tube for the OTA. I may coat it in Carbon Fiber but i have time to toy with that idea.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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I will make the lens cell from wood using a circle cutter. What would i do without my drill press and this circle cutter. 
First the clear diameter hole(all the way through the 3/4" wood, than the lens diameter(thickness of lens), than the tube diameter(all the way through). The wood at the bottom of the hole is just scrap to prevent the blade from hitting the metal drill press table. I will make the lens retaining ring in the same fashion just with thinner wood.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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Here is a horrible picture(bad flash) of the lens cell with lens inside to check fit. It will be cleaned up, sanded, sealed, and painted. The lens looks all smudged and terrible here but it is actually in real good shape, i will clean it before installation. BTW excuse my hands i work outside for a living. 
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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dawsonian2000
professor emeritus
Reged: 07/26/06
Posts: 563
Loc: Riverview, FL, USA
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Hey Brian!
It is great to see you working on your 127mm project again. I see you have some priming done and you are fabricating your own finder scope. I really like the wooden lens cell you created with the circle cutting for it. How will you be holding the lens in place within the cell?
I will also be putting my circle cutter to use again when I begin work on my tripod, which should be this weekend. I can not wait to really put my 127mm to the test.
In the meantime, please keep those updates coming!
Mel
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Clear Skies, Forever!
The Vega Sky Center
10" (254mm) F/5.65 Home Built Fork Mounted Newtonian Reflector
5" (127mm) F/9.4 Home Built Refractor (under construction)
3.5" (90mm) F/11.1 "Vixen-Spec Modified" Konus Refractor
3.1" (80mm) F/6 Scopos ED APO Refractor
4.5" (114mm) F/8 Tasco 11te-5 Newtonian (under restoration)
2.4" (60mm) F/16.7 Tasco 7te-5 Refractor
2.4" (60mm) F/15 Jason Discoverer 313 Refractor
http://www.vega-sky-center.com
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GlennLeDrew
Pooh-Bah
Reged: 06/18/08
Posts: 1269
Loc: Ottawa, Ontario, Canada
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Brian,
I just did a Homer-esque 'D'oh!', and slap to the forehead. When I read your earlier progress report (months ago) in which you found what you called an alarming aperture restriction due to the focuser tube cutting into the optical path, I didn't realize then that I could have alayed your fears.
Your 'ray trace' diagram clearly represented the full light bundle across the eyepiece's field stop. In that case, the rather small clipping you found would be absolutely undetectable. The first main consideration in a visual 'scope is that the illumination be 100% at least on axis.
I'm dead certain that in your 'scope this condition is met, and then some. Lines drawn from the opposite sides of the objective's edge to the entrance of the focuser drawtube and then straight on to the image surface will show a not-too-small circle of full illumination. That's more than good enough!
In fact, in fast visual 'scopes it's often *beneficial* to introduce some form of baffle that causes a gradual decrease in off-axis illumination. Eyepieces that don't work so well at short f/ratios (e.g., Erfles) will deliver somewhat sharper images off-axis when the objective is partially masked to this off-axis light.
If you suffered even as much as 50% light loss at the field edge, as long as the fall-off was gradual (and it would be when the distant front end of the drawtube is the culprit) you would have to *really* look hard to see it.
So, rest easy!
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Home-made 11X50 right angle bino, 8.1 deg. FOV
Modified 26X100 bino, 3.5 deg. FOV
Home-made Mk II RA bino, using interchangeable objectives and eyepieces
My Gallery
Mediocre minds discuss people. Good minds discuss events. Great minds discuss ideas.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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I have been so busy with work that i put this off to the side but reading Mel's completion of his 127SS really got me charged to get this finished. Thanks Mel.  The picture of the wooden cell for the finder looks very rough but it actually worked out pretty well, i will show better pictures. I will seal it, prime it, and paint it. Hopefully that will prevent it from swelling and altering or pinching the optics (its only a finder anyway). I will cut another thinner wood ring from 5mm Okume plywood for the retaining ring, and pin it in place with three drops of epoxy on the field side of the ring so i can remove it down the road if necessary.
My company has changed my hours again these next two weeks so i wont be able to work on the scope until the weekends. But i will be able to keep a lookout for your tripod build Mel, i am looking forward to the build.
Thank you Glenn for making me fell better about my light path debacle. I will take your advice and build the scope as is, i should be happy with it as you have described. But thanks again for the explanation, i am slowly learning with this build.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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GlennLeDrew
Pooh-Bah
Reged: 06/18/08
Posts: 1269
Loc: Ottawa, Ontario, Canada
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Brian,
Glad to help!
To better absorb what could be hard to visualize from the verbiage I peviously spouted, you could try this first simple excercise. Draw straight lines from the objective edge to the *center* of the eyepiece field stop. You'll note how they easily fit through the drawtube's front opening with room to spare. As long as this condition is met, you're off to the races.
You won't believe how many commercial 'scopes (and an even greater percentage of binoculars!) I've seen over the decades that fail in this area.
The next thing to do is what I tried to describe in my previous post. That is, draw lines from the objective to the field stop plane that also just clip the drawtube's first opening. From these two rays you can directly measure the diameter of full illmination. If it's larger that about 1/5 or 1/4 of the largest field diameter you'll get at lowest power, your 'scope will perform perfectly well for visual use as far as field illumination goes.
I'd be curious to know what you get....
Cheers!
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Home-made 11X50 right angle bino, 8.1 deg. FOV
Modified 26X100 bino, 3.5 deg. FOV
Home-made Mk II RA bino, using interchangeable objectives and eyepieces
My Gallery
Mediocre minds discuss people. Good minds discuss events. Great minds discuss ideas.
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dawsonian2000
professor emeritus
Reged: 07/26/06
Posts: 563
Loc: Riverview, FL, USA
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Quote:
Thank you Glenn for making me fell better about my light path debacle. I will take your advice and build the scope as is, I should be happy with it as you have described. But thanks again for the explanation, I am slowly learning with this build.
... and doing a fantastic job, Brian. I look forward to seeing the new photos of the cell.
I will be posting my steps under the "Surplus Shed 127 mm refractor build" thread, so please stay tuned. In the meantime, you can take a look at the construction pages of a prototype field tripod I built for a friend. We call it the North Star Field Tripod. It was featured in the March/ April 2009 issue of ATT magazine. But, I also have a section that covers its construction on my website. You can find it at this link: http://www.vega-sky-center.com/index_ns_tripod.html
Please let me know if you assistance with navigating the pages.
The new North Star II will utilize aluminunm plate support brackets on each leg instead of the continuous bulky pieces of plywood I used on the North Star I prototype. Plus it will have a smaller pan-head. The aesthetics will be improved substantially.
Mel
--------------------
Clear Skies, Forever!
The Vega Sky Center
10" (254mm) F/5.65 Home Built Fork Mounted Newtonian Reflector
5" (127mm) F/9.4 Home Built Refractor (under construction)
3.5" (90mm) F/11.1 "Vixen-Spec Modified" Konus Refractor
3.1" (80mm) F/6 Scopos ED APO Refractor
4.5" (114mm) F/8 Tasco 11te-5 Newtonian (under restoration)
2.4" (60mm) F/16.7 Tasco 7te-5 Refractor
2.4" (60mm) F/15 Jason Discoverer 313 Refractor
http://www.vega-sky-center.com
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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Well i have been working weird hours but i have been sneaking time for the build in. Here is the finder tube with the carbon fiber epoxied on, it is dull from heat shrink wrapping it, i need to sand it and add some layers of epoxy.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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I have finally came to a decision on how the heck i am going to mount this puppy. Since it will be a Alt/Az fork mount i thought radius blocks, than i thought rings, and i couldn't make up my mind so i decided on "radius wings". Thats right radius blocks with wings. I started with thin sheets of plywood that you would find at a hobby store.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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I took a spare piece of tube that is the same diameter as my OTA and wrapped it in plastic wrap. It looks wrinkled in the picture but i pulled it tighter after the shot was taken.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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I brushed a thin layer of 2 part epoxy onto the wrap. Then i laid a layer of carbon fiber on top of the epoxy applying more epoxy to the top of the CF. Next a layer of plywood and more epoxy on that, then another layer of plywood etc.... I did four layers of plywood then i topped it off with a final layer of CF with epoxy brushed on top. Now i had a CF/plywood ham sandwich with the CF as the rye bread,the ply as the ham. and the epoxy as the mustard. I then covered the lot with heavy plastic sheet as seen in the picture. After i took duct tape and wrapped the whole bunch really tight. The picture shows only half the duct tape done, i ended up covering all the surface with duct tape forcing all the epoxy into the plywood and CF, and conforming the composite into the shape of my tube radius.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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After the epoxy set up, i removed the CF sandwich from the mold and cut to shape on the band saw. And i drilled the holes for the tube mounting screws.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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I cut radius blocks from some hardwood scrap i had laying around. And drilled mounting screw holes into them, i also added some CF to the ends of the blocks.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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Here is a shot of a slurry of epoxy mixed with wood flour to a consistency of peanut butter. It is mixed to thicken and strengthen the epoxy so i can mate the wings with the radius blocks.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
Edited by Happy-Idiot (06/19/09 09:42 AM)
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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I predrilled and countersunk two wood screws as extra security, they will be hidden under felt anyway. You don't want to squeeze all the slurry out of the gap.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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After the slurry set up i vacuumed bagged some CF onto the sides of the radius wing combo. Here i taped off the existing CF that i didn't want the new CF to stick to.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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I then sanded the CF surfaces with 100 grit and added layers of epoxy sanding with a flat block in between coats. When i was satisfied with the layers i sanded with 220 grit and down to 320, then varnished two coats.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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Not my best work, the wood shows through on the CF. I wish i would have spent some more time and not rushed, but it is fine for now. They may not look sturdy but they are REAL strong, the blocks will have added metal to prevent any breaks(overkill). This is a bad shot, it looks dusty but that is just the reflection of the flash and the saw dust on the drill press table.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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dawsonian2000
professor emeritus
Reged: 07/26/06
Posts: 563
Loc: Riverview, FL, USA
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Hey Brian,
I thoroughly enjoyed reading and seeing the progress and ingenious innovative method you came up with to mount your refractor! Those "radius-wings" will help to keep your instrument lighter yet rigid. Even though you say you do not like the wood layers showing more than the CF on the edges of the wings, I think it adds a tasteful contrast to the pieces.
So I see you are going to make your finder tube from CF too. Looking forward to seeing the results.
Brian!... You really know your stuff when it comes to fabricating. Congratulations!!!
Mel
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Clear Skies, Forever!
The Vega Sky Center
10" (254mm) F/5.65 Home Built Fork Mounted Newtonian Reflector
5" (127mm) F/9.4 Home Built Refractor (under construction)
3.5" (90mm) F/11.1 "Vixen-Spec Modified" Konus Refractor
3.1" (80mm) F/6 Scopos ED APO Refractor
4.5" (114mm) F/8 Tasco 11te-5 Newtonian (under restoration)
2.4" (60mm) F/16.7 Tasco 7te-5 Refractor
2.4" (60mm) F/15 Jason Discoverer 313 Refractor
http://www.vega-sky-center.com
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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Quote:
Brian!... You really know your stuff when it comes to fabricating.
I am just winging it. 
But seriously, it is a learning experience. For all i know after it is completed the tube may fall off the mount. I have limited experience with carbon fiber but it is fun to work and play around with. What i didn't show you were the first blocks i made, they were made from pine wood and i didn't vacuum bag the CF to the wood. So the cf delaminated off the wood while setting up, it also split in half while drilling a simple 1/2" countersink hole(i should have used a forstner bit instead of a brad point bit), thats what working at two o'clock in the morning does to you. Pine was a poor choice and a mistake, but the tighter grained mahogany i used here is like iron compared to it, it still soaked up the epoxy and the cf has mated to it perfectly. I will reinforce the hole with sleeves of brass and a washer to distribute the pressure. My tube is aluminum and is fairly light, the focuser is the GSO style and is light as well. Thank you for the compliment Mel but i am in the begining stages of what can be done with CF. I do have to say that the radius wings are as solid as a rock,and not in the least bit brittle. I am not a big fan of the well known MAS epoxy, i find it to be brittle, i know i am going to catch flak for writing that but i like RAKA epoxy. RAKA brand is a little known epoxy made by a gentleman down in Fla. It is a slow epoxy with good saturating power that seeps into the fiberglass and wood and is not the least bit brittle after it cures.
The only reason i can get away with making these radius blocks is that the OTA wall is so thick that i can thread the radius mounting bolts into the side wall of the OTA.
Now that the radius blocks are done i can use them as a template to drill the holes into the tube and thread them. This is what has been holding me up with the painting of the tube.
Mel i have been watching your progress on your mount and i am very impressed. I can't wait to see the final result, if it is anything like your past projects i am sure we are in for a treat.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
Edited by Happy-Idiot (06/19/09 10:06 AM)
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dawsonian2000
professor emeritus
Reged: 07/26/06
Posts: 563
Loc: Riverview, FL, USA
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Quote:
Mel i have been watching your progress on your mount and i am very impressed. I can't wait to see the final result, if it is anything like your past projects i am sure we are in for a treat.
For me, the above also applies to you too, Brian.
Mel
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Clear Skies, Forever!
The Vega Sky Center
10" (254mm) F/5.65 Home Built Fork Mounted Newtonian Reflector
5" (127mm) F/9.4 Home Built Refractor (under construction)
3.5" (90mm) F/11.1 "Vixen-Spec Modified" Konus Refractor
3.1" (80mm) F/6 Scopos ED APO Refractor
4.5" (114mm) F/8 Tasco 11te-5 Newtonian (under restoration)
2.4" (60mm) F/16.7 Tasco 7te-5 Refractor
2.4" (60mm) F/15 Jason Discoverer 313 Refractor
http://www.vega-sky-center.com
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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I am almost finished with the finder, i may not use it for this ATM. I may remove the diagonal and move the objective out to use it as a straight through finder for a Newt ATM.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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objective and CF retaining ring.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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I painted the tube a Satin "MA-Bell " green. Notice i masked off the front where i will be mounting the lens cell. It is a tight fit so i didn't want to build it up with paint.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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The radius wings with lime green felt. I tapped the tube and purchased some stainless 1/4 by 20 bolts to hold the OTA to the radius blocks. I still have to drill and tap the dovetail to mount the radius blocks to it.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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The tail end of the tube with the adaptor plate and stainless hardware. Again i tapped the tube to accept the bolts. The tube is thick and takes the tap very well.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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The Antares single speed focuser. It will need to be laser collimated before i add the lens cell.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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One last look at the knife edge baffles before mating the lens cell to the tube.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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dawsonian2000
professor emeritus
Reged: 07/26/06
Posts: 563
Loc: Riverview, FL, USA
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The finder turned out great, Brian! If you are not going to use it on the 127mm, what are you going to use for a finder on the 127mm, if any?
Mel
--------------------
Clear Skies, Forever!
The Vega Sky Center
10" (254mm) F/5.65 Home Built Fork Mounted Newtonian Reflector
5" (127mm) F/9.4 Home Built Refractor (under construction)
3.5" (90mm) F/11.1 "Vixen-Spec Modified" Konus Refractor
3.1" (80mm) F/6 Scopos ED APO Refractor
4.5" (114mm) F/8 Tasco 11te-5 Newtonian (under restoration)
2.4" (60mm) F/16.7 Tasco 7te-5 Refractor
2.4" (60mm) F/15 Jason Discoverer 313 Refractor
http://www.vega-sky-center.com
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dawsonian2000
professor emeritus
Reged: 07/26/06
Posts: 563
Loc: Riverview, FL, USA
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Wow! Your 127mm shorty is looking fantastic! I like the color you chose as well. But, I thought you were going to go with the blue like mine. In any case, it is looking beautiful. It looks like you had to do a bit of shimming of the focuser adapted. You did a fine job there as well.
Like you, I also did not paint the very end of the tube, because of the snug fit of the objective cell. Actually, as you may recall, I sanded the interior of the cell to aid in easier fitting onto the tube. Man!... Your scope is looking good!
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Clear Skies, Forever!
The Vega Sky Center
10" (254mm) F/5.65 Home Built Fork Mounted Newtonian Reflector
5" (127mm) F/9.4 Home Built Refractor (under construction)
3.5" (90mm) F/11.1 "Vixen-Spec Modified" Konus Refractor
3.1" (80mm) F/6 Scopos ED APO Refractor
4.5" (114mm) F/8 Tasco 11te-5 Newtonian (under restoration)
2.4" (60mm) F/16.7 Tasco 7te-5 Refractor
2.4" (60mm) F/15 Jason Discoverer 313 Refractor
http://www.vega-sky-center.com
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dawsonian2000
professor emeritus
Reged: 07/26/06
Posts: 563
Loc: Riverview, FL, USA
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Now THAT'S an excellent baffling job! First rate job! Congrats! Looks very professionally done. Though mine are positioned correctly inside of the tube, the internal aesthetics are no where near the look of yours! Simply awesome! Can you take an image a little further back with the baffles in focus? Another beautiful job, Brian!
As for my 127mm, I will start working on the tripod this weekend.
Mel
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Clear Skies, Forever!
The Vega Sky Center
10" (254mm) F/5.65 Home Built Fork Mounted Newtonian Reflector
5" (127mm) F/9.4 Home Built Refractor (under construction)
3.5" (90mm) F/11.1 "Vixen-Spec Modified" Konus Refractor
3.1" (80mm) F/6 Scopos ED APO Refractor
4.5" (114mm) F/8 Tasco 11te-5 Newtonian (under restoration)
2.4" (60mm) F/16.7 Tasco 7te-5 Refractor
2.4" (60mm) F/15 Jason Discoverer 313 Refractor
http://www.vega-sky-center.com
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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Mel,
I also sanded the cell as well as the tube end...and sanded... and sanded. If you look at the beginning of my thread you will notice i changed most every decission at least twice. including the color.
I mounted the cell and lens on the tube today, so far so good. I need to find something cylindrical that is the same diameter as my dewshield needs to be, so i can use it as a form for the Carbon Fiber dewshield.
As far as a finder is concerned i am burnt out, i tried to make a finder bracket that would adjust up/down left/right and it looks horrible. I will probably make some rings or even adapt some old Unitron 40mm rings and build a RA finder scope with CF.
Mel I am following your SS refractor build thread very closely, keep up the great work!
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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Quote:
Can you take an image a little further back with the baffles in focus?
Focus? My eyes don't focus anymore that is why i built a widefield, so i don't have to worry if the smudge in the sky is in focus. My eyes aren't what they used to be.
Still not the best picture but maybe this will be beter than the last.
I used paintable silicone and cleaned the excess up with a long straight edged stick.
Edited by Happy-Idiot (07/12/09 08:27 AM)
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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Last night my Brother Inlaw showed up with some simple fountain fireworks, the kids had a blast. While i was seeing everyone out to their cars i looked up and saw the conditions were about a 7.5 out of 10, no dew, clear skies, no big chunk of cheese in the sky. So i decided to bring two scopes out, one was a MN56 that i ATM'd onto a dob mount, and the other was my new SS 127mm on a modified SCT Fork mount. I know i don't have a dewshield on the scope yet but it was dry out and i was dying to try this baby out.
It was late but since school is out i invited my 14 yr old son(who's middle name happens to be Orion) out with me. Having my son with me turned my 7.5 night into a 10 out of 10 night. We started off with one of my favorites the celestial TEA POT Sagittarius, and the Lagoon Neb. I was surprised that the SS127 beat the MN56 in contrast, the nebula seem brighter and the background darker i guess the baffles paid off or maybe its that the MN has a secondary obstruction. Same goes for the Omega and Trifid Nebulas both very contrasty and pleasing. I thought for sure that the MN56 would do better with M13 but i was wrong, using the same eyepieces i found SS127 was again brighter, maybe not more detail but brighter. The MN56 wasn't dead by no means, its views of Jupiter were nice, crisp, and clear with pinpoint moons, and as expected the SS127 was like most fast refractor with a significant amount of violet fringing. It had its fair share of CA on bright stars and showed a good share on the later rising moon.
Overall i am very happy with this scope, it is a inexpensive fast large aperture refractor that was not only fun to build but is fun to cruise the Milky Way. It gives nice bright contrast views of large nebulas and incredible views of open clusters with a definite WOW factor. If you get the opportunity to purchase one of these SS lens do yourself a favor and grab it. I will post a few pictures of the finished scope when the dewshield is complete. At the rate i work it will probably be around 2011. 
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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dawsonian2000
professor emeritus
Reged: 07/26/06
Posts: 563
Loc: Riverview, FL, USA
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Hey Brian,
Now that is an awesome baffle job! Congratz!
Mel
--------------------
Clear Skies, Forever!
The Vega Sky Center
10" (254mm) F/5.65 Home Built Fork Mounted Newtonian Reflector
5" (127mm) F/9.4 Home Built Refractor (under construction)
3.5" (90mm) F/11.1 "Vixen-Spec Modified" Konus Refractor
3.1" (80mm) F/6 Scopos ED APO Refractor
4.5" (114mm) F/8 Tasco 11te-5 Newtonian (under restoration)
2.4" (60mm) F/16.7 Tasco 7te-5 Refractor
2.4" (60mm) F/15 Jason Discoverer 313 Refractor
http://www.vega-sky-center.com
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dawsonian2000
professor emeritus
Reged: 07/26/06
Posts: 563
Loc: Riverview, FL, USA
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Hi Brian,
Thanks for the report on the SS127. Isn't it great to have your kids out to share in all that Heavenly Glory! I love it when they take part and ask thoughtful questions.
I am very happy to know that the SS127 is a great performer. Especially against the MN56!I would love to have the shorter version of the SS127 to go with mine. It should make a nice light bucket for DSO imaging. As for the better constrast you experienced, I have noticed that refractors seem to edge reflectors of comparable size. I guess it can be contributed to the closed optical system and less reflective surfaces as compared to the MN56.
Congratulations, on building a great instrument!
Mel
--------------------
Clear Skies, Forever!
The Vega Sky Center
10" (254mm) F/5.65 Home Built Fork Mounted Newtonian Reflector
5" (127mm) F/9.4 Home Built Refractor (under construction)
3.5" (90mm) F/11.1 "Vixen-Spec Modified" Konus Refractor
3.1" (80mm) F/6 Scopos ED APO Refractor
4.5" (114mm) F/8 Tasco 11te-5 Newtonian (under restoration)
2.4" (60mm) F/16.7 Tasco 7te-5 Refractor
2.4" (60mm) F/15 Jason Discoverer 313 Refractor
http://www.vega-sky-center.com
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astrodan13
member
Reged: 12/03/08
Posts: 19
Loc: Suffolk County, Long Island, N...
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Hey brian! Nice job!I can't wait to come by one night and have a look through it. Wish I had the time and patience to try making one. It has to be very rewarding to look through something you've made. Take care and keep up the good work! Dan.
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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Thank you Dan. One of these nights we will have to meet up and you can see the ATM.
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Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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droid
rocketman
Reged: 08/29/04
Posts: 4037
Loc: ohio
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 well..........come on we need to see the completed scope.......pictures people pictures...... 
Sorry could resist.........wow tis thread got past me.
Brian you are head and shoulders above me when it comes ot wood working.
I will add one note though...and Im sure your aware of it, but...when working with epoxy , please take all precautions, gloves mask , lots and lots of ventilation.
I say this because when I firt started building high power rockets, in an effort to complete them in time for launches I would sometimes work in my hobby room indoors.
Ive since developed a rather nasty allergic reaction to epoxy.
ok back to the photos...oh and bye theway I f you ever tire of the 127,, send it my way
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12 inch Truss Reflector "John"
102mm Celestron C102HD
Tasco 7TE5 60mm Classic
Tasco 9TE5 60mm Classic
Celestron Ultima 2000 SCT
Remains of an 8 inch dob
Celestron Comet catcher(orange tube)
1960 Edscorp Space Conquerer 6inch f/8
10x50 Bushnell Binoculars.
11T 4.5 inch Tasco reflector Lunograsso?
60mm Telescope Club
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mikey cee
Post Laureate
Reged: 01/18/07
Posts: 3520
Loc: bellevue ne.
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Patience my man after all this is a "fasty"! 
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7x35 and 10x50 sears tower binocs, 3" f/10 edmunds reflector, 2.4" f/11.7 manon refractor, 6" f/8 jaegers refractor, "The 8 Ball" 8" f/13.3 brandt refractor, 3" f/15.8 sans&streiffe refractor, 3.1" f/15 selsi refractor(towa 339), 2.4" f/15 sears refractor, selsi 30x30mm spyglass, criterion 5-draw 25x45x75x spyglass(1957), 4.25" f/14.8 tasco 20te.
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swcrawford
member
Reged: 06/15/08
Posts: 31
Loc: Western Tennessee, USA
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Brian,
First let me say that I am truly impressed with your workmanship. Your carbon fiber work is really nice. I have to say that carbon fiber and wood laminated together look very cool. Maybe one day I'll give it a try.
I just received an email from Surplus Shed that this lens is back in stock and immediately ordered one (got to be quick with these). I would very much like to duplicate your success so I have some questions.
First, I understand that you bought an aluminum tube with a 5" outside diameter from a local supplier. Was this an irrigation sort of company or just a general metal supplier? What was the wall thickness? Also, I read that you had to sand the inside of the objective cell to fit the tube. What method did you use to do this? How did you maintain an even thickness on the wall of the plastic cell, or did you worry very much about sanding too much off one side or the other?
I know that you used the 'scope on a stick' method to figure the length of the tube with various eyepieces and a diagonal. What tube length did you decide on for this scope? Were you planning to use this scope visually only or possibly for astrophotography?
What model Antares focuser did you use? You mentioned that you were planning to trim the focuser tube slightly. Did you do this, or did you find it acceptable without trimming? I think you used a single speed focuser. Was this acceptable for your purposes or would you use a dual speed focuser if you were doing it over again?
Thanks for giving us such a detailed look at your build process. I hope to use your experience in my own build.
Best Regards,
SC
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10" LX200 EMC
ST-80
Atlas EQ-G mount
ETX125PE
Canon EOS Digital Rebel 300D [unmodified]
Phillips SPC900NC [unmodified]
Meade DSI 2 color
Homebuilt Portable Power Supply
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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Quote:
Brian,
First let me say that I am truly impressed with your workmanship. Your carbon fiber work is really nice. I have to say that carbon fiber and wood laminated together look very cool. Maybe one day I'll give it a try.
Thank you SC i hope you decide to give it a go, if you look at my start date and today's date you will notice i am a slow worker. I have been very busy so it is a treat for me when i do find the time to pick the scope up and start working on it. I still need to get going on the dewshield.
Quote:
I just received an email from Surplus Shed that this lens is back in stock and immediately ordered one (got to be quick with these). I would very much like to duplicate your success so I have some questions.
Good thinking make sure to get your order in they have been on back order for awhile.
Quote:
First, I understand that you bought an aluminum tube with a 5" outside diameter from a local supplier. Was this an irrigation sort of company or just a general metal supplier? What was the wall thickness?
It was actually from a local welder friend but i didn't want to make it a complicated story so i said local supplier. Mine is 1/8" thickness. I think alittle thinner would be better if you are concerned with weight(the weight limit on your mount). I have dealt with these guys in the past with good success.
Quote:
Also, I read that you had to sand the inside of the objective cell to fit the tube. What method did you use to do this? How did you maintain an even thickness on the wall of the plastic cell, or did you worry very much about sanding too much off one side or the other?
The sanding was so tiny i shouldn't even have had mentioned it(it just took forever). Most of the sanding was on the outside of the tube and i used a long sheet of fine grit sandpaper by itself like polishing your shoes with a cloth. I just keep turning the tube 1/8th turns so it was evenly sanded. Very primitive but for the small amount i took off it was sufficient. When i was close i found if i put the tube in the freezer and heated the cell with a hair drier and put them together it slipped on perfectly. But i don't recommend this method because the cell is only plastic and could crack when the tube warms up to its correct size at room temperature.
Quote:
I know that you used the 'scope on a stick' method to figure the length of the tube with various eyepieces and a diagonal. What tube length did you decide on for this scope? Were you planning to use this scope visually only or possibly for astrophotography?
Only visually due to the CA, i may give it a try with AP but i don't expect the greatest quality images, beside i am a hack when it comes to AP anyway. 
Quote:
What model Antares focuser did you use? You mentioned that you were planning to trim the focuser tube slightly. Did you do this, or did you find it acceptable without trimming? I think you used a single speed focuser. Was this acceptable for your purposes or would you use a dual speed focuser if you were doing it over again?
The basic GSO focuser that Agena and Scopestuff sells. I guess a dual speed would be nice for such a fast scope to really fine tune the stars to pinpoints but the knobs on these GSO focusers are so large that i don't find the need for a dual speed. Besides i wanted to build this scope on the cheap side because even though this is a fun scope scope it is still limited in use. Please don't get me wrong i have no regrets with this scope but it is no Takahashi. No i didn't trim the drawtube yet, but i didn't have time to give it the once over either. I still need to take it out on a good night and tweak the collimation and see if there is any vignetting.
Quote:
Thanks for giving us such a detailed look at your build process. I hope to use your experience in my own build.
Best Regards,
SC
I have had a boat load of fun with this build and i will continue having a great time using this scope. As long as you don't expect apo views you will be satisfied as well. I hope you have as much fun as i have had. I posted this so others could use some of my ideas or even learn from my mistakes and who knows maybe some of my work will spark an new idea or brainstorm into something extraordinary. BTW thanks for the kind words.
--------------------
Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
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Mike Lynch
member
Reged: 04/07/06
Posts: 52
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Brian,
I'm considering mounting my SS 127mm f/5.5 in an aluminum tube from Hastings Irrigation. (PVC hasn't worked as well as I had hoped.)
May I ask the thickness of your tube? I presume the OD is exactly 5"....?
What length did you determine is optimal? I've measured about 15.75 inches.
Thanks,
Mike Lynch
Frankfort KY USA
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Mike Lynch
member
Reged: 04/07/06
Posts: 52
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Hmmmmm... If I'd looked at the last post in this thread, I'd have seen the answers for at least TWO of my questions. Time to WAKE UP!! 
Mike Lynch
Frankfort KY USA
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dawsonian2000
professor emeritus
Reged: 07/26/06
Posts: 563
Loc: Riverview, FL, USA
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Hey Mike,
If I may jump in here, I purchased a Hastings tube for my 127mm f/9.4. The O.D. is exactly 5" and and the wall thickness I chose was the .078". The only issue I had to deal with was that the interior of the objective cell had to be sanded to be able to slide over the tubing up to the tube stop. It took a bit of time, but it worked out just fine. I got the idea from Allan Overcast.
I completed my f/9.4 some time ago and I am still working (slowly) on completing the tripod.
Hope this info helps.
Mel
--------------------
Clear Skies, Forever!
The Vega Sky Center
10" (254mm) F/5.65 Home Built Fork Mounted Newtonian Reflector
5" (127mm) F/9.4 Home Built Refractor (under construction)
3.5" (90mm) F/11.1 "Vixen-Spec Modified" Konus Refractor
3.1" (80mm) F/6 Scopos ED APO Refractor
4.5" (114mm) F/8 Tasco 11te-5 Newtonian (under restoration)
2.4" (60mm) F/16.7 Tasco 7te-5 Refractor
2.4" (60mm) F/15 Jason Discoverer 313 Refractor
http://www.vega-sky-center.com
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Mike Lynch
member
Reged: 04/07/06
Posts: 52
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Mel,
Thanks! I did notice from a few messages back that a 5" OD aluminum tube and/or the inside of the cell needs some sanding. I'll keep this in mind and be ready to patiently sand one or the other off a bit... probably the tube.
Mike Lynch
Frankfort KY USA
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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Hello Mike, i had some sanding to do as well, it was time consuming but there is a reward at the end. ....Big biceps.
As far as the tube length you need to figure what focuser you are using, i used a Antares and it might be different if you are using another brand. Best bet is to make a refractor on a stick method and you can't go wrong.
--------------------
Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
|
dawsonian2000
professor emeritus
Reged: 07/26/06
Posts: 563
Loc: Riverview, FL, USA
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My pleasure! As Brian mentioned, be prepared for the benefit of bigger biceps.
Hey! Don't forget to checkout Brian's CD Knife-Edge Baffles! I used his concept in my OTA and they are awesome!
Mel
--------------------
Clear Skies, Forever!
The Vega Sky Center
10" (254mm) F/5.65 Home Built Fork Mounted Newtonian Reflector
5" (127mm) F/9.4 Home Built Refractor (under construction)
3.5" (90mm) F/11.1 "Vixen-Spec Modified" Konus Refractor
3.1" (80mm) F/6 Scopos ED APO Refractor
4.5" (114mm) F/8 Tasco 11te-5 Newtonian (under restoration)
2.4" (60mm) F/16.7 Tasco 7te-5 Refractor
2.4" (60mm) F/15 Jason Discoverer 313 Refractor
http://www.vega-sky-center.com
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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An update.. I am having a blast with this scope, i notice a little softness at the edge which doesn't;t bother me because it is slight. The wide field views are astounding, stars are crisp, contrast is not bad at all. Perfect example last night even with so so conditions i picked out part of the veil nebula using a Meade 32mm SWA. I screwed in a OIII filter and BAM! one of the arc just popped in no problem giving me one of the best views of the veil i have ever had, and WITH A REFRACTOR NO LESS!
The double cluster is to die for with this big guy, Pleiades is another incredible view. I saw a hint of pink/purple color on the Great Orion Nebula, i know some people see green i see pink. Many also say you need a 10" newt to see any color from the GON but i think they are mistaken. The crab was like picking a strawberry out of a bowl of cheerios with its wide field contrastive views and big light grasp. I couldn't keep the scope off of Andromeda. Maybe it was from using small 60mm scopes for the past two years but it felt like i was discovering these simple DSO's all over again.
I have been dragging my feet finishing the dewshield, but the weird thing is out of the three scopes i had set up last night the 127SS was the only one that didn't fog up???? It had the biggest glass and was the only one with no dewshield??? I thought it would have been the first to fog. 
Still no finder either. 
--------------------
Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
|
dawsonian2000
professor emeritus
Reged: 07/26/06
Posts: 563
Loc: Riverview, FL, USA
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Hey Brian!
What an amazing report on your 127mm! You should be very proud of the ingenuity and efforts you put into building such a fine performing telescope. Now you have got me wishing I had mine ready. I can't wait to see how my scope will perform. The Double Cluster is one of my favorites. In my 90mm f/11, it knocks me out. So you got me thirsting to push a bit harder to get my 127mm up and operational. Sounds like I am in for a new awakening when I get the opportunity to see the Double Cluster through it.
What eyepieces did you use during your observations? Are you planning to do any imaging with your scope?
Thanks again for sharing your observation notes. Please consider recording them so you can reflect back on them in the future. They indeed make for some real happy memories.
Mel
--------------------
Clear Skies, Forever!
The Vega Sky Center
10" (254mm) F/5.65 Home Built Fork Mounted Newtonian Reflector
5" (127mm) F/9.4 Home Built Refractor (under construction)
3.5" (90mm) F/11.1 "Vixen-Spec Modified" Konus Refractor
3.1" (80mm) F/6 Scopos ED APO Refractor
4.5" (114mm) F/8 Tasco 11te-5 Newtonian (under restoration)
2.4" (60mm) F/16.7 Tasco 7te-5 Refractor
2.4" (60mm) F/15 Jason Discoverer 313 Refractor
http://www.vega-sky-center.com
|
dawsonian2000
professor emeritus
Reged: 07/26/06
Posts: 563
Loc: Riverview, FL, USA
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Hey SC,
It has been quite some time since you reported that you purchased a Surplus Shed objective. Have you started construction yet?
Mel
--------------------
Clear Skies, Forever!
The Vega Sky Center
10" (254mm) F/5.65 Home Built Fork Mounted Newtonian Reflector
5" (127mm) F/9.4 Home Built Refractor (under construction)
3.5" (90mm) F/11.1 "Vixen-Spec Modified" Konus Refractor
3.1" (80mm) F/6 Scopos ED APO Refractor
4.5" (114mm) F/8 Tasco 11te-5 Newtonian (under restoration)
2.4" (60mm) F/16.7 Tasco 7te-5 Refractor
2.4" (60mm) F/15 Jason Discoverer 313 Refractor
http://www.vega-sky-center.com
|
Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
|
|
Mel, you are a Gentleman, thanks for the kind words. I can't wait for you to get yours outside either i know you will love it. Just make sure the focuser is collimated dead center.
I only used the 32mm SWA Meade it is a 2", i have some other eyepieces i would like to try in the scope on my next clear night. I would like to try one of my Naglers as well as my 16mm Galoc and UO koenig.
I really need a dewshield and finder, i wanted to make a finder bracket for my CF finder but i am so busy that i think i am better off just mounting a 8x50 from my collection.
--------------------
Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
|
swcrawford
member
Reged: 06/15/08
Posts: 31
Loc: Western Tennessee, USA
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Mel,
I just about have the scope finished. I have the tubing for the dew shield but I haven't started on it yet. Of course then I have to come up with some rings and a dovetail plate. One of these days It'll get first light.
Big thanks to Brian, since I basically followed this thread as a build plan. That made it a lot easier seeing all the steps and how they fit into the big picture.
Regards,
Shawn
--------------------
10" LX200 EMC
ST-80
Atlas EQ-G mount
ETX125PE
Canon EOS Digital Rebel 300D [unmodified]
Phillips SPC900NC [unmodified]
Meade DSI 2 color
Homebuilt Portable Power Supply
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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Shawn where did you buy the dewshield? How is the fit? That is my bigest hangup. BTW the scope looks fantastic. You surprised me with saying you followed my lead, i didn't think anyone besides Mel read my post here. 
Does your scope use baffles or is it flocked?
--------------------
Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
|
swcrawford
member
Reged: 06/15/08
Posts: 31
Loc: Western Tennessee, USA
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|
Brian,
I ordered a 12" length of 6" OD x .083" tube from Velocity Air. I tried to fit it as soon as it arrived. The burrs on the inside of the pipe shaved a super thin, curly length of plastic off the ribs on the lens cell. Once I filed the burrs away it fit nearly perfectly. So maybe just a light sanding on the ribs on the lens cell is needed to get it to seat correctly against the stop. The outer diameter of the pipe is the same as the outer diameter of the dew shield stop so the lines blend well. Sorry for the lousy picture below, it was taken with my phone.
I had a circle cutter for the drill press so I cut baffles from CD's and taped them down as you illustrated so I didn't have any shatter on me. I'll probably have to re-do them after I study the theory on baffling a bit more. I didn't quite 'get' the whole desired illuminated field thing. I just sort of followed my intuition.
I also sprayed several layers of textured paint on the inside of the tube and then flat black over that. It worked just as promised to help hold the baffles as I siliconed them in place.
I really wasn't kidding. Your thread reads like a step by step plan. I've built other stuff but this was my first ATM scope, and a refractor to boot (refractors somehow seem scarier).
You could probably rename this thread to: "Anybody can build a decent 5 inch achromatic refractor on the cheap"!
Regards,
Shawn
--------------------
10" LX200 EMC
ST-80
Atlas EQ-G mount
ETX125PE
Canon EOS Digital Rebel 300D [unmodified]
Phillips SPC900NC [unmodified]
Meade DSI 2 color
Homebuilt Portable Power Supply
|
Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
|
|
I think i have A.D.D (no joking) and usually have to read things three times and even then i still have a hard time comprehending. So when i write a step by step sometimes i can go overboard with the details.
I really wanted to do a Carbon Fiber dewshield to save on weight but the hang up is finding a cylinder that has an OD exactly the Inside Diameter of my future dewshield. So thanks to you i am going to order the 6" OD tube from Velocity air and fill it with a two part compound, and when it dries i will have my mold for the Carbon Fiber dewshield. This has been a thorn in my side for awhile (i am a slow learner) so thank you Shawn. Then i can put this post to bed once and for all. 
I know my mini review of the scope seems to good to be true but i was writing from pleasure and not a technical standpoint. The other night i only used a 32mm eyepiece which was perfectly satisfying to me. I didn't bother looking at Jupiter again because i know there would be plenty of false color, this scope was built for widefield Milky Way strolling. And with that in mind i don't think i could have had more fun if it were a AP Starfire. Key word "FUN" i am not talking perfect Apo views i am talking relaxing enjoyable "look what i built that can collect light that is 2 million years old FUN". Just don't think you are going to be getting these fantastic views of Mars with it, it is a RFT and thats what it excels at. A screwdriver doesn't make a good hammer, it will bang in a nail if you really work at it but a hammer is the better choice.  enough ranting, see i told you i have A.D.D i am now talking about hammering nails with screwdrivers. 
Besides fun the views really were to die for, and it performed a heck of alot better than i thought it would. Where can you get a 5" RFT for under $200 built custom with all the options you like. A scope built just for you. 
--------------------
Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
|
dawsonian2000
professor emeritus
Reged: 07/26/06
Posts: 563
Loc: Riverview, FL, USA
|
|
Quote:
Mel, you are a Gentleman, thanks for the kind words. I can't wait for you to get yours outside either i know you will love it. Just make sure the focuser is collimated dead center.
I only used the 32mm SWA Meade it is a 2", i have some other eyepieces i would like to try in the scope on my next clear night. I would like to try one of my Naglers as well as my 16mm Galoc and UO koenig.
I really need a dewshield and finder, i wanted to make a finder bracket for my CF finder but i am so busy that i think i am better off just mounting a 8x50 from my collection.
Brian,
The accolades are well deserved on your part. No need to thank me. Your work screams precision and great craftsmanship through and through. You are indeed a Master.
Regarding the focuser, one of the critical steps in building my 127mm was the centering of the focuser (as you so aptly mentioned). I used a laser collimator to make certain it was dead on. You probably already seen the process I illustrated on page 2 of the CN thread "Surplus Shed 127mm Refractor Build".
As for your CF finder; use it. You put a great deal of time and effort into its construction and it is deserving of being mounted on your 127mm.
Mel
--------------------
Clear Skies, Forever!
The Vega Sky Center
10" (254mm) F/5.65 Home Built Fork Mounted Newtonian Reflector
5" (127mm) F/9.4 Home Built Refractor (under construction)
3.5" (90mm) F/11.1 "Vixen-Spec Modified" Konus Refractor
3.1" (80mm) F/6 Scopos ED APO Refractor
4.5" (114mm) F/8 Tasco 11te-5 Newtonian (under restoration)
2.4" (60mm) F/16.7 Tasco 7te-5 Refractor
2.4" (60mm) F/15 Jason Discoverer 313 Refractor
http://www.vega-sky-center.com
|
dawsonian2000
professor emeritus
Reged: 07/26/06
Posts: 563
Loc: Riverview, FL, USA
|
|
Brian and SC,
I used the same exact tubing for my dew shield. I purchased mine from Hastings. I made the final length 9". It fits okay with the addition of Protostar adhesive flocking material on the inside of the dew shield. In any case, I have another ideal to add sections of dense foam rubber padding or other material between the four outer ribs of the objective cell to aid in firming up the connection.
Looking good SC!
Mel
--------------------
Clear Skies, Forever!
The Vega Sky Center
10" (254mm) F/5.65 Home Built Fork Mounted Newtonian Reflector
5" (127mm) F/9.4 Home Built Refractor (under construction)
3.5" (90mm) F/11.1 "Vixen-Spec Modified" Konus Refractor
3.1" (80mm) F/6 Scopos ED APO Refractor
4.5" (114mm) F/8 Tasco 11te-5 Newtonian (under restoration)
2.4" (60mm) F/16.7 Tasco 7te-5 Refractor
2.4" (60mm) F/15 Jason Discoverer 313 Refractor
http://www.vega-sky-center.com
|
Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
|
|
Velocity Air just sent me a e-mail that the tube is on the way. I like the long dewshield look not to mention Ron Ravneberg always made long dewshields, i forget the formula. I think it is something along the lines of the length should be three times the diameter.
--------------------
Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
|
BarabinoSr
sage
Reged: 11/17/05
Posts: 316
Loc: Slidell La
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Hi Brian!I've been following your thread with great interest because I assembled my own 5" f/9 Yulin refractor from purchased parts as well. It's interesting because if I were not able to get these parts I was prepared to build the scope from scratch.I like your scope itself, tube mounts and the great attention you paid to detail . As I mentioned in the 5" refractor rebuild,I am already planning to move this scope to a pedestal with a CG-5 mount.I will need a dovetail bar, and have one already. I had two but I gave one to Mel. There will be more coverage as this project takes shape.I have considered two options-construct a field tripod or mount it atop pedestal base.As it stands now,I would like to see this instrument riding the CG-5 on at least a 5' tall pedestal. The reasoning behind this is due to the aluminum tripod I'm currently using;it allows some flexure-ok but not to my standards. Stay Tuned! G
--------------------
12"GSO f/5.3" Newtonian Reflector 10" Meade LX-50 Fork Mounted Schmidt-Cassegrain
8" Hardin f/6 Newtonian reflector
6" Konus f/8 Refractor,Yulin 5"f/9 refractor,
4.5"TASCO Luminova f/9 Newtonian Reflector 4.5"TASCO 11TR(Lunagrosso) Red reflector
90mm Meade f/11 refractor,Tasco 10TE 76mm 1200mm f/l Refractor
60mm TASCO 7TE-5 1000mm f/16.7 Refractor 60mm TASCO 9TE 700mm f/l refractor
60mm TASCO 9TE-0 710mm f/l Refractor 50mm-TASCO 6TE-5 600mm f/l Refractor
Edited by BarabinoSr (11/24/09 05:38 PM)
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
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|
Thanks Gary,
I have been following your posts as well. I am looking forward to your completion, keep up the good work. It is great you are posting pictures with your detailed reports, you never know when someone will need that info in the future.
--------------------
Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
|
dawsonian2000
professor emeritus
Reged: 07/26/06
Posts: 563
Loc: Riverview, FL, USA
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|
Great news, Brian! I was considering making my dew shield 12" inches long, but I ended up cutting it to 9" long. I should have left it alone. I while back when I was looking up information on how long a dew shield could be, I found an article that stated it can be as short as the the diameter of your objective. ...And some say 2 to 3+ times the diameter of the objective. I don't know, so I decided on 9" inches. I should have gone longer, but I still like the length it is. I would definitely NOT make the length the same as the diameter of the lens. Go for long, my friend!
Mel
--------------------
Clear Skies, Forever!
The Vega Sky Center
10" (254mm) F/5.65 Home Built Fork Mounted Newtonian Reflector
5" (127mm) F/9.4 Home Built Refractor (under construction)
3.5" (90mm) F/11.1 "Vixen-Spec Modified" Konus Refractor
3.1" (80mm) F/6 Scopos ED APO Refractor
4.5" (114mm) F/8 Tasco 11te-5 Newtonian (under restoration)
2.4" (60mm) F/16.7 Tasco 7te-5 Refractor
2.4" (60mm) F/15 Jason Discoverer 313 Refractor
http://www.vega-sky-center.com
|
dawsonian2000
professor emeritus
Reged: 07/26/06
Posts: 563
Loc: Riverview, FL, USA
|
|
Hey! BTW - I did some more work on the tripod. Check it out when time permits.
Mel
--------------------
Clear Skies, Forever!
The Vega Sky Center
10" (254mm) F/5.65 Home Built Fork Mounted Newtonian Reflector
5" (127mm) F/9.4 Home Built Refractor (under construction)
3.5" (90mm) F/11.1 "Vixen-Spec Modified" Konus Refractor
3.1" (80mm) F/6 Scopos ED APO Refractor
4.5" (114mm) F/8 Tasco 11te-5 Newtonian (under restoration)
2.4" (60mm) F/16.7 Tasco 7te-5 Refractor
2.4" (60mm) F/15 Jason Discoverer 313 Refractor
http://www.vega-sky-center.com
|
Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
|
|
Quote:
Great news, Brian! I was considering making my dew shield 12" inches long, but I ended up cutting it to 9" long. I should have left it alone. I while back when I was looking up information on how long a dew shield could be, I found an article that stated it can be as short as the the diameter of your objective. ...And some say 2 to 3+ times the diameter of the objective. I don't know, so I decided on 9" inches. I should have gone longer, but I still like the length it is. I would definitely NOT make the length the same as the diameter of the lens. Go for long, my friend!
Mel
The tube arrived and is 12" but that would look kinda long for my OTA being considerably shorter than yours, your 9" looks perfect, i may go with a 9" as well. I like your flocking on the dewshield.
--------------------
Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
|
Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2818
Loc: 3rd Rock
|
|
Quote:
Hey! BTW - I did some more work on the tripod. Check it out when time permits.
Mel
When time permits??? Are you kidding? I have been glued to your post watching ever move. I am your biggest fan.
--------------------
Brian
A small scope that gets used often is a better investment than a big scope that stays in the closet.
Unitrons, you spend more time looking at them than you do through them.
|
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