#1  
Old 04-06-2020, 03:56 PM
Emuhead (Andrew)
Registered User

Emuhead is offline
 
Join Date: Oct 2019
Location: Melbourne, Australia
Posts: 221
Thin Spacers

Hi guys,

Where do you get your thin spacers?

Im pretty sure ill need M48 size.. and im after 2 specific sizes.
2.56mm & 7.9mm

Open to suggestions, Ive not used them before.

The variable spacer that i do have cant be used as its already too large at about 24mm and up.

Thanks,
Reply With Quote
  #2  
Old 04-06-2020, 04:16 PM
The_bluester's Avatar
The_bluester (Paul)
Registered User

The_bluester is offline
 
Join Date: Feb 2011
Location: Kilmore, Australia
Posts: 3,342
Bintel has a set of M48 extension tubes with a 5mm in it and I know Sidereal Trading brought in some thin stainless ones when I bought a few. You would have to stack a couple of the spacer washer ones to make up the 2.5 (Not sure you would get 2.56 exactly) and a threaded 5mm tube and spacer washers to get to 7.9mm. Other than that you would have to get something made I reckon.
Reply With Quote
  #3  
Old 04-06-2020, 04:18 PM
glend (Glen)
Registered User

glend is offline
 
Join Date: Jun 2013
Location: Lake Macquarie
Posts: 7,033
Not sure about M48s but you can buy packs of very thin nylon spacers, as thin as 0.25mm, 0.5mm. 1mm, etc. I bought mine from Teleskop-Express. They are made by Baader. They simply slip on over you adaptor threads, to tune exactly the length of spacing you require. Link here.

https://www.teleskop-express.de/shop...ol---15pc.html

BTW, most Correctors have a working range, and do not necessarily need precision like 2,56mm, they could work well 50% either side of that probably.
Reply With Quote
  #4  
Old 04-06-2020, 05:14 PM
The_bluester's Avatar
The_bluester (Paul)
Registered User

The_bluester is offline
 
Join Date: Feb 2011
Location: Kilmore, Australia
Posts: 3,342
The only problem I have found with the Baader ones is that they are designed as a close fit over the threads, you have to push them on and down in to position, that is OK in itself but they can be a royal pain to remove. I cant recall if they do M48 ones though.

I mention the spacer washers Sidereal Trading has as I know that they have some M48 ones and they are already here in Aus, which is sadly a factor at the moment. The stainless washers are an expensive option (I more or less sent about $50 worth with a scope I just sold to help the new owner get it up and running) but it looks like the M48 extension tubes are on backorder at the moment but it is worth checking with them if they have just had some come in. Bintel may or may not have them on the shelf at the moment but as far as I know they don't carry the M48 spacer washers. Sidereal Trading bought some extras when I bought a set through them last year.
Reply With Quote
  #5  
Old 04-06-2020, 05:19 PM
Xeteth (David)
Registered User

Xeteth is offline
 
Join Date: Jul 2019
Location: Melbourne, Australia
Posts: 129
I'd give anything for some sort of product that you can do variable spacing and adjust for tilt also. I know it's unlikely since there might be a lot of moving parts, plus it would have to hold sometimes quite a hefty imaging system but damn it would make adjusting backfocus a much nicer procedure.
Reply With Quote
  #6  
Old 05-06-2020, 05:56 AM
The_bluester's Avatar
The_bluester (Paul)
Registered User

The_bluester is offline
 
Join Date: Feb 2011
Location: Kilmore, Australia
Posts: 3,342
The problem I have seen with pretty well any variable spacing adjuster is that the tilt changes all on it's own any time you so much as look at them, OK on something slow with a big critical focus zone but harder and harder to deal with as the optics get faster..

Tilt adjustment wise these look like a good idea, using a cone shape, tapered radial screws and heavy springs to adjust tilt without push/pull screws, which are a PITA to adjust and also often blocked access wise.


https://www.gerdneumann.net/english/...ting-unit.html

Last edited by The_bluester; 05-06-2020 at 06:18 AM.
Reply With Quote
  #7  
Old 05-06-2020, 06:35 AM
Joshua Bunn's Avatar
Joshua Bunn (Joshua)
Registered User

Joshua Bunn is offline
 
Join Date: Oct 2011
Location: Albany, Western Australia
Posts: 1,459
Quote:
Originally Posted by Emuhead View Post
Hi guys,

Where do you get your thin spacers?

I can make you there if needed.


Quote:
Originally Posted by Xeteth View Post
I'd give anything for some sort of product that you can do variable spacing and adjust for tilt also. I know it's unlikely since there might be a lot of moving parts, plus it would have to hold sometimes quite a hefty imaging system but damn it would make adjusting backfocus a much nicer procedure.

I'm currently making a variable spacer for a customer here on IIS so he can easily dial in his corrector spacing. You can contact me if you'd like to discuss having one made
Reply With Quote
Reply

Bookmarks

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 03:14 AM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Advertisement
Bintel
Advertisement
Testar
Advertisement