neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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Yep...this is the guilty one.
This summer a fellow astronomer from our local forum donated me an old, pretty fragile aluminum tripod from an EQ 1 mount or something.
So finally after a couple of weeks with a rocky health I started to tune this baby up a little. Decided to change the hole base which is ridiculous tiny. So I went to my country house the last weekend and turned on my home made lathe some plywood disks which will be glued togather with epoxy to form a solid ~5" base.
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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The new base
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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Some drawings before tooling..
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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The plywood base is made of 4 sheets 7mm thick. The idea would be to cut the last one to insert the 1" aluminum brakets which will connect the legs of the tripod.
So I've started to drill 1" holes first and tommorow I'll finish to cut the hole thing. Then epoxy  ...lots and lots of epoxy.
In the end I'll bind all three legs by aluminum tubing to make the tripod as stiff as possible.
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
Edited by neo (10/27/09 02:58 PM)
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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..
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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wmyers
member
Reged: 01/23/08
Posts: 44
Loc: High Point, NC
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thanks for the pics Neo, looking forward to seeing the finished project.
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Orion 120 ED Refractor
Feathertouch Focuser
Orion Atlas EQ-G goto mount
Orion 80 guidescope w/Starshoot autoguider
AstroTech 2" quartz diagonal
Canon Rebel XT
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magic612
professor emeritus
Reged: 09/30/08
Posts: 561
Loc: Somewhere south of Chicago, IL
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Hey, I've got a tripod like that from a 4.5" reflector I rescued. OTA is on a GOTO mount now, so the tripod has been sitting there unused, because it's... well, as you said neo - old and fragile.
I'll be watching your progress with much interest. 
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- Celestron C8+, Orion 90mm f/10, Orion ST-80, 5" f/8 Dob, 127mm f/9.4 refractor, 114mm f/8 on DS GoTo, 60mm Sears 6333-A, 127mm f4.4 refractor lens (current project), 12" f/5 mirror (future project)
- Orion Vista 10x50s (5 deg), Sears #6207 7x35 (7 deg), Jason #138 Statesman 7x35 (11.5 deg)
Yes, I'm addicted to telescopes and binoculars. I am getting help. Every time I look at the heavens, it helps.
http://www.eyesonthesky.com
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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Thanks guys!
Well...a little update..
Today I've finished cutting the plywood disk and I've cut the three brakets which will hold the legs. This brakets are simply 1" aluminum tubing which will be glued and tied up with screws to the plywood base.
Some pics during fooling around with dangerous power tools 
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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...
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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The base with the 3 brakets in place.
I've drilled the holes for legs screws. In order not to wear out the thinn aluminum brackets because of the screws I plan to epoxy some 8mmOD x 6mmID round tubing on each of them. So the legs screws will hold on a much larger area.
Tommorow I'll finally glue the base togather and I'll drill the rest of the holes.
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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Happy-Idiot
Carpal Tunnel
Reged: 04/06/06
Posts: 2836
Loc: 3rd Rock
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Outstanding work!  I love these posts.
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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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magic612
professor emeritus
Reged: 09/30/08
Posts: 561
Loc: Somewhere south of Chicago, IL
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I'm liking where this is going.
What scope(s) are you planning on using with it, neo?
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- Celestron C8+, Orion 90mm f/10, Orion ST-80, 5" f/8 Dob, 127mm f/9.4 refractor, 114mm f/8 on DS GoTo, 60mm Sears 6333-A, 127mm f4.4 refractor lens (current project), 12" f/5 mirror (future project)
- Orion Vista 10x50s (5 deg), Sears #6207 7x35 (7 deg), Jason #138 Statesman 7x35 (11.5 deg)
Yes, I'm addicted to telescopes and binoculars. I am getting help. Every time I look at the heavens, it helps.
http://www.eyesonthesky.com
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deSitter
Carpal Tunnel
Reged: 12/09/04
Posts: 2928
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This is nice, but because the entire scope weight is bearing on the interface of aluminum to wood, I think I would secure the leg bosses from below with machine screws - drill through the wood and aluminum then tap out to the needed size - cap off with a hex nut epoxied in place. Nice wood work!
-drl
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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Thnks again guys! You're to kind. I had no idea that a humble tripod would be so popular 
- drl...of course I have that allready in plan for today. I'll secure with two screws and epoxy each bosse...bracket...whatever ..thanks for observation.
Well...the tripod is mainly for my 70mm Rodenstok lens refractor which I'm currently trying to rebuild. But I believe that after all the tweaks are done I can load it with much bigger scopes in the future.
I still have to buy some more supplies for this project including a new set of thumbscrews and a nice blue bag from Telescope House 
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
Edited by neo (10/30/09 02:07 AM)
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grendel
sage
Reged: 04/12/09
Posts: 250
Loc: Canterbury, Kent, UK
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you could of course replicate the wood you already have and sandwich the aluminium sections between two lots of wood.
grendel
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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Quote:
you could of course replicate the wood you already have and sandwich the aluminium sections between two lots of wood.
grendel
I've thought of that too. But first of all I wanted a thick solid base, second, I wanted to keep the legs ends a bit beneath it to get more clearance for the rest of the mount. The problem is that the aluminum tubing is 1" thick and the plywood is 0.27" so in order to build a full base with that sandwich configuration it gets bit more complicated. I like to keep it simpe for this project  .
Ok boys...I'm out to buy some epoxy... 
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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All righty then ! 
Some progress today...
I've finished to drill all the holes (to many ) and to cut the small tubes which will hold the legs screws.
Then, epoxy time...
Today, while I went down to the local hardware store I jast got the idea of using some 1" table legs covers for the brackets. The result is quite nice, I believe.
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
Edited by neo (10/30/09 04:02 PM)
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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Before glueing...
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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Finally the big moment...glueing the base.
Tommorow will be the moment of truth . 
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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droid
rocketman
Reged: 08/29/04
Posts: 4046
Loc: ohio
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neo..I hope your wearing a respirator or have lots of air movement while using epoxy, in some people , exposure leads to allergic reaction to the slighttest whif of it, Im in that boat from building rockets indoors in the winter.Just a heads up.
Very nice Job though,
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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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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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Thanks for the worning. I had no trouble with this kind of epoxy, and it states nothing on the label about being harmful in normal use condittions or anything. It smelles a little bad, but that is the only discomfort so far. I guess other types of epoxy are far more dangerous.
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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Two more pics...
The bisonite used on brackets is cured so.. ready for business.
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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Just checking how it looks....
I don't unclamp the base yet. I'll leave it to cure for a few more hours just to be safe.
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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Yey..the base is finished!  
This evening I've drilled the holes in the base for the screws which will secure the aluminum brackets. After the final mounting I've coted the entier plywood disk with a good layer of epoxy to seal it off. Nice finish too.
I'm still wondering if to paint it or not. What do you think???
So here it is....
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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And of course I couldn't resist and I've mounted the legs to see who it looks.
Pretty dandy
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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deSitter
Carpal Tunnel
Reged: 12/09/04
Posts: 2928
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This is nice work - I would fill the countersunk area over the screws that secure the leg bosses with some sort of wood putty.
=drl
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deSitter
Carpal Tunnel
Reged: 12/09/04
Posts: 2928
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I would definitely paint it matte black and bevel the top edge.
Now you need to make a cool accessory tray!
It's very nice aluminum work!
-drl
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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Thanks man!
Yep, I was thinking about using some matte black paint on it. I'll sleep on it until later after I finish fabricating.
Next I plan to reinforce the legs and make them collapsible. I'll use a thick threaded rod tied up on the base through which a bushing can run. The bushing is between to nuts. From that bushing I can connect three piece of aluminum tubing to the each leg and when I'm tightening the two nuts the tripod becomes rock solid. I've used the same system on other wood tripod I have and works great. I can sit on it.
And of course a nice eyepiece tray would be the final step.
So busy, busy, busy...
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
Edited by neo (11/01/09 04:48 AM)
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wmyers
member
Reged: 01/23/08
Posts: 44
Loc: High Point, NC
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Very nice, I've taken good notes..
thanks!!!
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Orion 120 ED Refractor
Feathertouch Focuser
Orion Atlas EQ-G goto mount
Orion 80 guidescope w/Starshoot autoguider
AstroTech 2" quartz diagonal
Canon Rebel XT
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sailor70623
scholastic sledgehammer
Reged: 01/12/08
Posts: 944
Loc: Ok.
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Well if you wood putty over the screw heads, I wouldn't paint it. But I like the look of wood. I'd make the accessory tray natural wood too.
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Corornado PST
LB 16" & 12"
Z 10"
LX50 8"
8" CPC
ETX127
102&90mm MAKs
80mm Richfield APO
70mm refractor
ETX60
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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Thanks guys for suggestions!
The screw heads aren't quite blank. The base is coated with a layer of epoxy so the screws are covered too but the epoxy is quite transparent so.... Besides I don't mind to much that the screw heads are visible, after all the base top will be covered by the rest of the mount so only the side will remain exposed.
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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A small update...
I've lowered the...how to call them  ...the original hinges on each leg. I'll use this hinges to attach the 3 arms (spacers) which will reinforce the tripod.
By setting the hinges lower helps to strenghten the tripod more.
Boy this was a boring job! 
Just drilling hole afte hole, 12 to be exact, then adjusting 12 screws. I thought it never ends.
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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The whole picture..
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
Edited by neo (11/05/09 02:05 PM)
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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Being very busy these last weeks at work, finally I got some spare time to look over my tripod again.
I got a long threaded rod, 14mm thick, which will be fixed in the center of the base and cut it at a desirable length.
Also I've made the bushing which runs on the rod.
The bushing is made of some sort of huge thick aluminum electrical connector for very thick wires I've found on the local hardware store. Luckily the inner diameter was perfect for what I need. Also on the bushing I've fitted three "U" shaped piece of aluminum, placed at 120 degrees which will hold the three arms...or spreaders I don't know exactly how to call them... for the each of the tripod's legs.
The bushing...
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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Here's the three spreaders after drilling the holes and the bushing after the epoxy was cured this morning. I just have to trim a bit these parts a bit for perfect fit and tomorrow, hopefully, I'll do a quick assembling.
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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Today I've finally got the chance to put everything together. And of course like an old saying in my country goes " rushing up like the bride to get married" in same way
I've rushed to get the job done and measured wrong the length of the spreaders. So they were more then 2" to long.
 
Well...I guess I skipped the "measure twice and cut once" part . Good think that the spreaders were to long and not to short
Here's a pic after trimming them..
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
Edited by neo (11/19/09 04:38 PM)
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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Here's the tripod with the new look. I have to do some adjustments here and there in order to be able to collapse it entirely but not big deal.
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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The threaded rod will be adjusted too. I'll make another bushing which will be fixed in the base of the tripod and everything will be secured with a nut beneath.
another one
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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magic612
professor emeritus
Reged: 09/30/08
Posts: 561
Loc: Somewhere south of Chicago, IL
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Looking good, neo. I'll be very interested to see how stable this tripod is for your scope.
--------------------
- Celestron C8+, Orion 90mm f/10, Orion ST-80, 5" f/8 Dob, 127mm f/9.4 refractor, 114mm f/8 on DS GoTo, 60mm Sears 6333-A, 127mm f4.4 refractor lens (current project), 12" f/5 mirror (future project)
- Orion Vista 10x50s (5 deg), Sears #6207 7x35 (7 deg), Jason #138 Statesman 7x35 (11.5 deg)
Yes, I'm addicted to telescopes and binoculars. I am getting help. Every time I look at the heavens, it helps.
http://www.eyesonthesky.com
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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Thanks magic!
Well I've tested it a bit and it's pretty much rock solid, anyway much solid than it was constructed. I've let myself with a lot of my weight on it and I couldn't move it, twiste it or anything. Anyway I don't plan to use this tripod for very heavy scopes. I tune it mainly for my 70mm Rodenstock refractor but I guess it could hold even an 8" scope. Because it's light it would be perfect for star parties when the summer will come.
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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arpruss
scholastic sledgehammer
Reged: 05/23/08
Posts: 858
Loc: Waco, TX
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Are you going to fill the legs with sand to reduce vibration and increase stability?
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Coulter Odyssey 13.1" split-tube
Coulter Odyssey 8"
Home-made 7.8" F/4 dobsonian travel scope
Home-made 68mm F/5.3 achro (typically used as finder on 13.1")
Skymaster 15x70
BPTs4 8x30
32mm Plossl, 30mm Rini, 27mm Kellner, 13mm Hyperion, 6mm TMB/BO Planetary, Owl 2X Barlow
Palm TX with AstroInfo and RescoViewer
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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I've thought of that but I wasn't sure if that would help with something. This aspect would have been the next question I'd ask around here. Anyway the tripod got a bit of weight with all that metal and wood on it and I guess the final decision will be when I'll put a scope on it. Filling the tripod with sand would be an easy opperation anyway and I could do it even after is paint on it.
If you have any suggestions and advices about this aspect I'd sure need one. I don't have experience with thin aluminum tripods and I don't know exactly how it deals with the vibrations issue. I guess I'll learn on the go.
--------------------
Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
Edited by neo (11/20/09 09:59 AM)
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StarStuff1
scholastic sledgehammer
Reged: 04/01/07
Posts: 990
Loc: South of the Mason-Dixon Line
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You could also fill the legs with concrete. Makes them more stable and lowers the center of gravity.
--------------------
Tools that make objects very far away appear much closer than they actually are.
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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Concrete?! 
I wonder how heavy it gets after that treatment? But it's an interesting idea.
Today I've solved the issue of collapsing the tripod. The problem was that the hinges top screws were hitting the spreaders at half way so I just reversed them and used some special nuts...I don't know how to call them in english...you'll see in picture what I mean.
Here's the tripod completly collapsed. Works like charm...
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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And the nuts I was talking about. By the way, help me stock my vocabulary  ....how are called this type of nuts?
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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StarStuff1
scholastic sledgehammer
Reged: 04/01/07
Posts: 990
Loc: South of the Mason-Dixon Line
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Acorn nuts!
BTW, concrete weighs about the same as sand and you will not have sand grains falling out. You can also mix sand with glue to keep it in the tripod legs.
--------------------
Tools that make objects very far away appear much closer than they actually are.
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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Oh thanks a lot!
I'll try the concrete idea when I'll have the time. I guess I should make it a little bit thinner cause it would be hard to pour inside the legs without messing everything around.
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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hwhall
member
Reged: 09/22/08
Posts: 189
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Quote:
And the nuts I was talking about. By the way, help me stock my vocabulary ....how are called this type of nuts?
Those are also called cap nuts.
Your tripod work looks very professional and has been a joy to watch. Thank you!
--Wayne
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arpruss
scholastic sledgehammer
Reged: 05/23/08
Posts: 858
Loc: Waco, TX
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I've been told it's good for sand to be loose--this helps damp vibration. If we make it into a solid mass with glue or concrete, the mass can vibrate as a whole. When I did this to a friend's scope, I used a funnel to fill the legs within about 3/4" of the top, and then I filled the rest with silicone sealant. I also used a coarser sand--playground grade (50 lbs for less than $5 at Lowes).
The legs feel surprising now--they look light, but when you pick them up, they have a heavy and professional feel.
--------------------
Coulter Odyssey 13.1" split-tube
Coulter Odyssey 8"
Home-made 7.8" F/4 dobsonian travel scope
Home-made 68mm F/5.3 achro (typically used as finder on 13.1")
Skymaster 15x70
BPTs4 8x30
32mm Plossl, 30mm Rini, 27mm Kellner, 13mm Hyperion, 6mm TMB/BO Planetary, Owl 2X Barlow
Palm TX with AstroInfo and RescoViewer
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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Thanks guys! Most appreciated.
Arpruss...what you say seems to make a lot of sense. I mean the core of the legs should act like a shock absorber. Concrete it's not a good materaial for dumping vibrations, thats why it craks when an earth quake occures. I also believe that we need an elastic medium , that's why wood legs are so appreciated. I wonder if I can do better by mixing the sand with silicon. I could take advantage of the heaviness of sand and the elasticity of silicon in the same time. It would resemble somehow with a samurai sword, a stiff shell and a flexible core.
Anyway, by then here's the nut I imagined these days to fix the threaded rod to the base. So I need someone to do me favor on the lathe.
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
Edited by neo (11/22/09 04:30 PM)
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magic612
professor emeritus
Reged: 09/30/08
Posts: 561
Loc: Somewhere south of Chicago, IL
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neo - can you get "T" nuts in Romania? Here's a drawing of what they look like, along with the technical specs:
http://www.nutty.com/pdfcharts/t_nut.pdf
I'm sure they are available in metric sizes, if that's what you're using for threaded parts.
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- Celestron C8+, Orion 90mm f/10, Orion ST-80, 5" f/8 Dob, 127mm f/9.4 refractor, 114mm f/8 on DS GoTo, 60mm Sears 6333-A, 127mm f4.4 refractor lens (current project), 12" f/5 mirror (future project)
- Orion Vista 10x50s (5 deg), Sears #6207 7x35 (7 deg), Jason #138 Statesman 7x35 (11.5 deg)
Yes, I'm addicted to telescopes and binoculars. I am getting help. Every time I look at the heavens, it helps.
http://www.eyesonthesky.com
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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Yea, but I couldn't find a T nut that big anyware, I mean for M14 screws (more than 1/2"). And on top of that it has to be custom made. The OD should be 20mm and the flange 30mm.
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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magic612
professor emeritus
Reged: 09/30/08
Posts: 561
Loc: Somewhere south of Chicago, IL
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That is a rather large size! Hope you're able to find someone to do the metal cutting for you.
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- Celestron C8+, Orion 90mm f/10, Orion ST-80, 5" f/8 Dob, 127mm f/9.4 refractor, 114mm f/8 on DS GoTo, 60mm Sears 6333-A, 127mm f4.4 refractor lens (current project), 12" f/5 mirror (future project)
- Orion Vista 10x50s (5 deg), Sears #6207 7x35 (7 deg), Jason #138 Statesman 7x35 (11.5 deg)
Yes, I'm addicted to telescopes and binoculars. I am getting help. Every time I look at the heavens, it helps.
http://www.eyesonthesky.com
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grendel
sage
Reged: 04/12/09
Posts: 250
Loc: Canterbury, Kent, UK
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you also need to specify the hole through the centre, is this threaded (what thread) and the general diameter of the hole if not threaded (just an observation from one who makes his living doing CAD drawings for manufacture)
Grendel
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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Oh sure. Thanks for observation. I just posted a quick 3D representation of the T nut. The 2D drawing which will be in machinist's hands will have all the data needed. The 3D image is made with Alibre Design and the hole is already drawn automatically by the program with a M14 thread standard. I just couldn't find yet how to indicate all the dimensions on the 3D view, but they all appear in the 2D one. I see it indicates only the extrusion dimensions.
--------------------
Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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ColoHank
professor emeritus
Reged: 06/07/07
Posts: 516
Loc: western Colorado
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Quote:
I'll try the concrete idea when I'll have the time.
If you must add weight, consider lead or steel shot instead, and don't cement it. Loose shot attenuates vibrations very well. That's what is used to damp rebound forces inside a "no-bounce" mallet.
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Questar 3.5 standard - pyrex and BB coatings
Powerguide II
8mm, 12mm, 16mm, 24mm and 32mm Brandons
modified Bogen 3030 w/ homebuilt wedge
Homebuilt Galileo scope and very large and ugly homemade tripod
other odds and ends, including iPod Touch with StarMap Pro (what a marvelous combo)...
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"Nothing exists but atoms and empty space. Everything else is opinion."
Titus Lucretius Carus 99-55 B.C.
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neo
professor emeritus
Reged: 02/12/08
Posts: 623
Loc: Iasi, Romania
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Very interesting idea! Thanks. Although I don't know if I'm able to get real shots. But I guess I could use small ball bearings instead. I'd need ball bearings to mill my rouge anyway.
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Russian 15x50 binos
Home made 8" f/5 Newton on eq mount
Home made 70mm f/6 (Rodenstock Rotelar lens) Apo refractor
www.astronomy.ro
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