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The How to Thread

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#1 mdowns

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Posted 03 December 2022 - 10:33 PM

   After listening to some suggestions by long-time forum members(thanks JW, Terra and Robert) as well as discussing among the moderators we've decided to create a new 'pinned' thread. The 'How-To' thread. The point and focus of this thread are simple. Collect answers to the many questions we see asked over and over again, often distracting from other classic forums, and put the answers in one place, here,in the 'how to thread. Are you an expert in using Zen or Buyee? Please explain in a simple step-by-step manner, how you do it as well as any suggestions that might help your fellow forum members. Or maybe you don't know how or understand using Paypal, Stripe or Square, ask here. Above all, please suggest here, your proven methods or answers to questions many others might have. From crown and flint orientation to shipping from Japan, fast collimation to simple star testing. Please provide links whenever possible. Have you dealt with a seller on any of the online sites you'd like to recommend? Please do so and provide a link if possible. However, do not trash a seller or vendor you've had a bad experience with. Rather if you see someone ask about eBay seller ABC, that just cheated you, pm that person your reasons for concern. Let's let our other threads stay on track and at the same time grow this 'how-to' thread for everyone's benefit. Any topic that has or might be raised in classics is appropriate for this forum.This is the place for questions and answers!

                                                                                         Index

Adding pictures to your post       see post #20,page 1

Baffles made easy by clamchip     see post #9,page 1

Baffle Placement by Couder          see post #22,page 1

Collimation suggestions  for fast mirrors by ccwemy and clamchip, see post #11,and post #12,both page 1

Craigslist scope searching,near and far suggestions, see post #13 and #14,page 1

Cross-hair installation by clamchip, see post #29,page 2

Crown and Flint Orientation by Kasmos, see post #30,page 2

Disassembly and Reassembly hints by Couder, see post #2,page 1

Facebook,finding only scopes close to me, see post #8,page 1

Finding your old,posted pictures by Kasmos,see post #50,page 2

Flocking suggestions by clamchip   see post #10,page 1

Focuser (old school)  repair by clamchip  see post #27,page2

Go To conversion of a Super C8 using Onstep by KMHammer here

Meade  LX5 and LX200 electronics schematics by rferrante,see post #28,page 2

Nicotine Removal by clamchip.see post #46,page 2

Single Stalk maintenance tips, by clamchip,see post #33,page 2

Simple DIY 1.25" adapter for RAO  by Senex Bibax,see post #47,page 2

Refractor collimatable cell disassembly and reassembly by deSitter,see post #38,

Zero depth(almost) .965 to 1.25" adapters by ccwemyss,see post #53,page 3


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#2 Couder

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Posted 03 December 2022 - 10:58 PM

I would suggest following my directions - take plenty of digital pictures before, during disassembly, during repairs, and during reassembly. Take them from different angles. They cost nothing now, easy to delete, but if you take one piece off before another, then try to put them together the other way, it won't work. I keep all bolts/screws in marked places on a piece of cardboard (punch holes with an awl) and mark them. Little things like this can save hours of time when you have to take it all apart again because you find a piece, washer, or bolt after it is reassembled. Then you wonder where it goes. I do a lot of restoration on antique scopes/mounts and associated equipment, and these are especially prone to have had screws/bolts replaced. Sometimes a thread stripped, so even though they look alike, some might be SAE and the one that looks just like it is Metric. 

I have it all written down here:

 

http://www.justfurfu...tion Primer.htm


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#3 Kasmos

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Posted 04 December 2022 - 01:47 AM

Since it's asked so frequently I thought a pinned thread on how to clean, remove objectives, and the spacing of them is very much needed.

But a catch all 'How To' thread seems a little too general to me and will be hard to find the particular topic by someone looking for such advice.


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#4 davidc135

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Posted 04 December 2022 - 04:03 AM

I often find it hard to locate information using Search and wish there was an old fashioned index arranged alphabetically. But a collection of topics and descriptions might end up vast and sprawling long before it became comprehensive.

 

I'd love to see an organised index but giving links to descriptions located elsewhere. To work well it might need a person or team to do the organising.

 

David


Edited by davidc135, 04 December 2022 - 04:07 AM.

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#5 mdowns

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Posted 04 December 2022 - 07:28 AM

Thanks guys for the suggestions. What we can do is update the opening post with list in an Index form as suggestions or questions begin to accumulate.For example,

 

 Couder's Disassembly and Reassembly hints,see post #2,page 1

 

Once enough post have been generated we can organize these in an easy to read index,all contained within the threads opening post


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#6 Couder

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Posted 04 December 2022 - 09:45 AM

I agree - sometimes I do a search for an item and get no results. Do the same search with different words, it shows up including the words I used to search the first time. I've had computers since they were available to consumers - we had to load the operating system from a large floppy disk. I taught computer usage and worked the help desk while working at Shell Oil, and there have been "glitches" since day 1. 

Possibly an index broken down by type of equipment (mounts, refractors, reflectors, other types, accessories) and then those categories broken down into subcategories would be a starting point? 

This would indeed be useful not only for beginners, but those of us that buy a new-to-us scope and need to adjust the clutch, worm mesh, or collimate would also find it useful.


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#7 jkmccarthy

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Posted 04 December 2022 - 06:38 PM

Since it's asked so frequently I thought a pinned thread on how to clean, remove objectives, and the spacing of them is very much needed.

But a catch all 'How To' thread seems a little too general to me and will be hard to find the particular topic by someone looking for such advice.

Why not a "forum" rather than a thread ?  In other words:

 

Cloudy Nights ---> Equipment ---> Classic Telescopes ---> How-To FAQs

 

I think setting this up as a forum would eliminate (or at least make drastically easier) the burden on the moderators to organize and index the contributions, if each How-To frequently asked question/topic had its own thread.  Also, threads don't need to be sorted by "Recently Updated" (the default) but can instead be sorted alphabetically (under Custom, sort by "Topic Title" and "Sort Ascending (A-Z)".   Indeed, with some effort up front to create a structured list of How-To FAQ topic titles that was easy to navigate, a starter set of individual How-To topic threads could be created in advance (just as a framework) just devoid of content-containing posts.  Perhaps each topic thread might be start off with a moderator-generated 1- or 2-sentence post describing the intended scope of that particular thread ... with the content to be contributed later by the relevant subject matter experts / volunteers within our ranks.

 

01.00 Acquiring - How to Search & Buy Craigslist

01.01 Acquiring - How to Search & Buy Estate Sales

01.02 Acquiring - How to Search & Buy Facebook Marketplace

* * *

01.## Acquiring - How to Search & Buy Yahoo Japan Auctions (Zen, Buyee, etc.)

* * *

 

02.01 Adjusting - How to Adjust Collimation

02.02 Adjusting - How to Adjust Finderscopes

02.03 Adjusting - How to Adjust Focusers (Crayford)

02.04 Adjusting - How to Adjust Focusers (Rack and Pinion)

02.05 Adjusting - How to Adjust Mounts (Alt-azimuth)

02.06 Adjusting - How to Adjust Mounts (Equatorial)

* * *

 

03.01 Cleaning - How to Clean Eyepieces

03.02 Cleaning - How to Clean Fungus & Mold from Optics

03.03 Cleaning - How to Clean MCT & SCT Correctors

03.04 Cleaning - How to Clean Star Diagonals (Mirrors + Dielectrics)

03.05 Cleaning - How to Clean Star Diagonals (Prisms)

03.06 Cleaning - How to Clean Reflector Primary Mirrors

03.07 Cleaning - How to Clean Reflector Secondary Mirrors & Diagonals

03.08 Cleaning - How to Clean Refractor Objectives (Achromat Elements)

03.09 Cleaning - How to Clean Refractor Objectives (Fluorite Elements)

03.10 Cleaning - How to Clean Refractor Objectives (Triplet Lenses)

* * *

 

04.01 Repairing - How to Fix ...

* * *

 

05.01 Restoration - How to Restore ...

* * *

 

06.01 Teardown - How to Disassemble ...

* * *

 

Numeric outline prefixes like the ones added above may not be necessary, but might give moderators more control over the alphabetized sequence than thread-topic names alone ... but some way to group similar topics together would be advantageous, I think.  Also TBD is whether (and how) to limit the scope to Classic Telescopes ... versus, say, moving the How-To FAQ forum up-one-level so it resides under "Equipment" rather than under "Classic Telescopes" ??  (e.g., "Cleaning Eyepieces" might draw-in more CN expertise if the How-To FAQ forum was under Equipment not under Classic Telescopes, and the same could be said for many FAQ topic threads suggested above -- certainly "Collimation" is another).   Or maybe each of the current Equipment forums should have its own forum-specific How-To FAQ forum pinned to it?

 

Clearly much more up-front thinking + effort would be needed before any scheme like this would be ready for implementation, and there certainly may be better approaches than the ones suggested here.

 

Food for thought, FWIW ...

 

       -- Jim


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#8 mdowns

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Posted 04 December 2022 - 10:44 PM

Many times in the past we've seen this simple question related to Facebook Marketplace raised in the eBay thread. How do I limit the displayed scopes for sale to those in my area? Really fast and easy fix.
First, go to the FB marketplace and put telescopes into the search box. Your location will show up and you can pick a search radius(I keep mine within 60 miles). By default, FB will show lots outside of your immediate area, even if you've picked 50 or 60 miles from your home.The location box will show 'all' (see the first pic).Screenshot 2022-12-04 10.14.50 PM.png    Choose local pickup to eliminate those you would have to have shipped or drive many hours to find(see the second pic)Screenshot 2022-12-04 10.17.52 PM.png . Once done your choices will be narrowed down. In the second screenshot, I can see two classics immediately,the 60 mm red Edmund 60 and the towa 4.5"f9 rfl.



#9 clamchip

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Posted 10 December 2022 - 11:17 AM

If you need a baffle, just for experimenting or permanent, this one is super easy to make.

This is the way the Clark's baffled some of their scopes, I copied it here in my photo from

cotton art paper.

You cut a long strip of paper, or steel, the Clark baffles are steel. I fold 90 and then cut

slits to the 90 crease. Roll and trim to length. I tape the joint, squeeze the cylindrical body

of the baffle to oblong to help keep it in place in the telescope's tube.

You can easily push these up and down the tube to find that perfect spot, and then make

a metal one and caulk it in place with a couple dabs of latex house caulk.

I actually have cotton versions in some of my scopes, they hold up fine and make a huge

difference in contrast.

Robert

 

IMG_9087.jpg


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#10 clamchip

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Posted 10 December 2022 - 11:40 AM

Flock Paper is a gift from heaven to kill damaging reflections. Amateurs have been doing this

for a long time but I think it has become kinda forgotten in recent years. I have many old

classic focuser and extension tubes, and star diagonal inlets lined with flock paper, that's where

I got the idea.  

Any craft store will have Flock Paper. Do a test to make sure the flock doesn't shed. A piece

of tape or give the sheet a shake to make sure the fine little flockie's stay put.

Cut to desired tubes etc. slide in place and you will be very surprised at the difference it makes.

Robert

 

IMG_0897.jpg

IMG_0899.jpg

IMG_9780.jpg

IMG_9779.jpg

post-50896-0-88541500-1550968618_thumb.jpg


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#11 clamchip

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Posted 11 December 2022 - 11:21 AM

You know me, I LOVE Coulter Odyssey telescopes.

They are fast at f/4.5 and also because they have a 1.25" focuser so you cant see

the whole primary making collimation a little more difficult.

Because of this fast speed collimation is critical.

I suppose these days f/4.5 is more the norm.

To get to the point of my post, I like to center mark these fast mirrors so I can use a

3-hole binder hole reinforcement ring on center and a Barlowed laser.

Draw your mirror on a piece of paper, fold into quarters, snip the tip off of the

folded pie shaped piece, unfold and carefully place on the mirror, use a sharpie thru

your snipped hole to mark the center of the mirror. Add the reinforcement ring.

If you use a compass like in my photo you will have the needed center and no folding

is neccessary.

Read the article in the Jan 2003 Sky & Telescope for barlow laser collimation by Nils Olof Carlin.

 

Robert

 

post-50896-0-99491700-1540508707.jpg


Edited by clamchip, 11 December 2022 - 12:12 PM.

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#12 ccwemyss

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Posted 11 December 2022 - 01:49 PM

I would add that, for laser collimation, this same mask can be used to get the secondary aligned so the laser spot is hitting the center of the primary. It can be challenging to see where the laser is on a very clean and reflective mirror. With the mask, it is clearly visible, easy to see how it is moving as the secondary is adjusted, and when it is dead center. Then the mask is removed and the primary adjusted to get the return beam centered on the collimator's target.

 

Of course this assumes that the collimator itself has been properly collimated to begin with, by mounting it in a rotating holder and ensuring that the spot, at a good distance, doesn't move when the collimator is rotated.

 

Even then, it is still a good practice to check the scope's collimation with a star.

 

Chip W.



#13 mdowns

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Posted 11 December 2022 - 04:09 PM

How do you find telescopes for sale near to yourself on Craigslist?

 

Go to the browser of your choice and put in your town or a town close to you and then craigslist.In my example,Ft,Myers is the closest town of any size,so I put in 'Ft Myers craigslist' into my search bar. At the top left of your first page is a search window,put in telescopeScreenshot 2022-12-11 3.51.32 PM.png .

 

Immediately,after entering, you will see scopes available within your search city.after you browse through the displayed choices you can go back to the drop down location choice on the top left of the page

 

Screenshot 2022-12-11 3.52.32 PM.png

.

 

Hit it and other locations will drop down.In my case,I could choose from south Florida,Miami,Port Charlotte and Sarasota and be redirected to craigslist scope listings in those communities.



#14 jkmccarthy

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Posted 11 December 2022 - 10:29 PM

To search CL (and now also FB marketplace) ads nationwide for a very specific and/or rare item, has anyone else ever used the web site, SearchTempest ?

 

http://www.searchtempest.com/

 

The interface is fairly intuitive (e.g., enter "any distance" from your zip code to search nationwide), and the returned search results are then opened in numerous individual tabs in your web browser (by region).

 

Advanced techniques for combining search keywords (e.g., to exclude ads with a given keyword, or to combine keywords into a "specific phrase" or to search for boolean AND or OR combinations of terms, are explained here:   https://searchtempes...vanced-Keywords ).


Edited by jkmccarthy, 11 December 2022 - 10:31 PM.

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#15 clamchip

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Posted 12 December 2022 - 02:51 PM

Nurse Mendy made some milk jug washers for my Jaegers 1 inch mount.

She sure knows her way around a #11 Exacto blade.

In the early days Edmund used leather washers, and these leather thrust washers

have the oh so perfect rotational friction.

Milk jug washers are really nice too. Good job Mendy.

Don't be shy about using Super Glue to mend things, Mendy glued this broken

C8 finder bracket, its as good as new. Use Loctite brand.

Robert

 

post-50896-0-35224500-1492621226_thumb.jpg

post-50896-0-50734700-1494711362.jpg


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#16 Terra Nova

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Posted 14 December 2022 - 04:45 PM

Nurse Mendy made some milk jug washers for my Jaegers 1 inch mount.

She sure knows her way around a #11 Exacto blade.

In the early days Edmund used leather washers, and these leather thrust washers

have the oh so perfect rotational friction.

Milk jug washers are really nice too. Good job Mendy.

Don't be shy about using Super Glue to mend things, Mendy glued this broken

C8 finder bracket, its as good as new. Use Loctite brand.

Robert

 

attachicon.gifpost-50896-0-35224500-1492621226_thumb.jpg

attachicon.gifpost-50896-0-50734700-1494711362.jpg

I did that exact thing for an Edmund or Jaegers mount I used to own (I’ve had several, big and small). They make great washer bearings.


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#17 mattyfatz

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Posted 15 December 2022 - 10:13 AM

One of the greatest restoration threads can be found here….

Chuck’s attention to detail, thorough descriptions, and accurate photos makes this thread an excellent guidebook to any refractor restoration. I have it saved, and reference it often.


Edited by mattyfatz, 15 December 2022 - 10:13 AM.

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#18 Kasmos

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Posted 15 December 2022 - 04:06 PM

Here's a 'How To' related to the last post.

 

After searching for an old topics, there's a way you can avoid seeing those annoying yellow highlighted search words in them.

 

All you need to do is remove the last portion of the the address in the browser past the last / in the address and hit return.


Edited by Kasmos, 15 December 2022 - 04:07 PM.

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#19 KMHammer

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Posted 23 January 2023 - 10:33 PM

For anyone interested, particularly those with Celestron C8 SCT's (specifically the Super C8 plus, but may work on others) I have created a How-to thread for making the mount/scope into a full GoTo mount using OnStep and readily available materials. It can be found by going to:

 

https://www.cloudyni...tep/?p=12336330

 

I am willing to assist anyone interested in modifying their own C8 with the process by answering any questions and supplying the necessary STL files (access to a 3D printer is necessary). Just reply in the thread first.

 

If you choose to do it on your own, I highly recommend that you read through the entire thread one or two times before starting to make sure you understand the process and the required skills/equipment. 


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#20 mdowns

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Posted 28 January 2023 - 09:43 AM

Adding Pictures to Your Post,follow these steps.

 

1 From your reply/post window go to the bottom right and choose 'more reply option's.  Screenshot 2023-01-28 8.09.49 AM.png

 

2 Next,from the bottom left of the window select 'choose',then select a file from your device   Screenshot 2023-01-28 8.10.22 AM.png

 

after choosing your file hit 'attach'       Screenshot 2023-01-28 8.10.57 AM.png

 

finally,put your cursor in your post where you want the pic to be and hit 'add to post'from the right side of the window

 

Screenshot 2023-01-28 8.12.19 AM.png

 

 


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#21 clamchip

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Posted 17 February 2023 - 12:54 PM

Maybe your newt isn't quite right?

Something easily missed when collimating is things like this in my photo.

It doesn't take much to bend these studs.

What you will end up doing is tweaking the mirrors to compensate and then

you start a whole avalanche of errors in the tube. A tweak here a tweak there and

pretty soon it might be close but it will never be perfect.

Make sure mechanics are are fine before collimation.

Robert

 

IMG_1268.jpg

IMG_1269.jpg


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#22 Couder

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Posted 17 February 2023 - 01:23 PM

If you need a baffle, just for experimenting or permanent, this one is super easy to make.

This is the way the Clark's baffled some of their scopes, I copied it here in my photo from

cotton art paper.

You cut a long strip of paper, or steel, the Clark baffles are steel. I fold 90 and then cut

slits to the 90 crease. Roll and trim to length. I tape the joint, squeeze the cylindrical body

of the baffle to oblong to help keep it in place in the telescope's tube.

You can easily push these up and down the tube to find that perfect spot, and then make

a metal one and caulk it in place with a couple dabs of latex house caulk.

I actually have cotton versions in some of my scopes, they hold up fine and make a huge

difference in contrast.

Robert

 

attachicon.gifIMG_9087.jpg

My Clarks have baffles like these. I have made baffles like you did, I cut the slits closer together, found it makes a nicer circle. As to where to place them:

I taped together poster board paper slightly longer than my refractor. Draw a line down the center, then put marks for the lens and where the drawtube are. Get a long straightedge, and draw lines between the ends as well as the tube. you should now have a life size drawing of your scope. Then divide the distance by however many baffles you are going to use and mark. Now from there you can tell just how big your baffles need to be for where they go in the tube by measuring between the light paths.

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#23 ErnH2O

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Posted 17 February 2023 - 02:05 PM

Maybe your newt isn't quite right?

Something easily missed when collimating is things like this in my photo.

It doesn't take much to bend these studs.

What you will end up doing is tweaking the mirrors to compensate and then

you start a whole avalanche of errors in the tube. A tweak here a tweak there and

pretty soon it might be close but it will never be perfect.

Make sure mechanics are are fine before collimation.

Robert

 

That would definitely introduce some errors.

Side question....would finer threads make it easier to fine tune the adjustments? 



#24 clamchip

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Posted 17 February 2023 - 04:34 PM

I'm going to replace those bent screws and I just might do that, finer threads.

I do like wing nuts because its easy to just do a "quarter turn" and remember where

you are.

 

Robert


Edited by clamchip, 17 February 2023 - 04:37 PM.

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#25 apfever

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Posted 17 February 2023 - 05:36 PM

That would definitely introduce some errors.

Side question....would finer threads make it easier to fine tune the adjustments? 

You bet.  A standard 1/4" bolt has 20 threads per inch and is called a 1/4-20. A fine 1/4" bolt has 28 threads per inch and is called a 1/4-28.  The fine thread has 40 percent more threads and will have 40 percent finer adjustment.  I found many cells use fine thread specs originally, and fine threads are my choice when making or modifying a cell. Also a good idea to keep the collimation bolts towards the outside edge as far as practical. The further out, the finer the collimation.

 

Maybe your newt isn't quite right?

Something easily missed when collimating is things like this in my photo.

It doesn't take much to bend these studs.

What you will end up doing is tweaking the mirrors to compensate and then

you start a whole avalanche of errors in the tube. A tweak here a tweak there and

pretty soon it might be close but it will never be perfect.

Make sure mechanics are are fine before collimation.

Robert

 

attachicon.gifIMG_1268.jpg

attachicon.gifIMG_1269.jpg

 

Cells like clamchip posted above often wiggle or jump when the lock bolts are applied. This is due to the tip of the lock bolt hitting on an edge and 'walking' the mirror ring off a small amount. Slightly rounding the tip of the bolt will help. Rounding lets the lock bolt hit in a small central area that won't push the mirror ring around. 

These cell types also tend to have flex and slop that can be cleaned up quite a bit. A T nut can make the long thin collimation bolts much more rigid. Shimming an oversized hole in the mirror ring to the collimation bolt will reduce the room the mirror cell has to move. Go to entry #79, page 4, link HERE.

 

Roberts cell is good for telescopes that can look around corners or other obstacles. 


Edited by apfever, 17 February 2023 - 05:38 PM.

  • clamchip likes this


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