Go Back   IceInSpace > Equipment > Equipment Discussions
Register FAQ Calendar Today's Posts Search

Reply
 
Thread Tools Rate Thread
  #1  
Old 30-09-2010, 08:20 AM
fuso (Anthony)
Registered User

fuso is offline
 
Join Date: Sep 2007
Location: melbourne
Posts: 29
Saxon focuser shift?

Hi guys,
I have a 2nd hand 8' Dob which seems to have a loose focuser.

This is very frustration. cus when I put my laser in for collimation moving the focuser up and down the laser beam also moves about 2 cm.
The only way it seems to stop it is when I tighten the 4 screws near the R&P and also lock the screw at the top of the focuser (I don't know what that screw is for)
It reduces the shift/slop but the affect is a very stiff and hard to turn focuser.
Any tips on how to improve my focuser would be greatly appreciated.

Thanks Anthony
Reply With Quote
  #2  
Old 30-09-2010, 08:44 AM
asimov's Avatar
asimov (John)
Planet photographer

asimov is offline
 
Join Date: May 2005
Location: Bundaberg
Posts: 8,819
All you can do is adjust it correctly to take out the slop. There will be a very fine line between no slop + too tight & hard to move versus minimal slop & easy to move. Talking about thou's here.

Other than that, perhaps an upmarket focusser is in order.
Reply With Quote
  #3  
Old 30-09-2010, 11:10 PM
astro_nutt
Registered User

astro_nutt is offline
 
Join Date: Mar 2005
Location: Melbourne
Posts: 1,013
I owned a Saxon 8" dob and found that there are 2 allen head grub screws on the topside of the focuser barrel. You will need to loosen off the 4 screws under the R+P. Then very carefully tighten the allen bolt closest to the scope' tube until you feel resistence then back off 1/8th of a turn. Do the same for the other allen bolt. Go back to the first one and tighten until you feel resistence then back off less then 1/16th of a turn. Do the same for the other allen bolt. You can then tighten the 4 screws under the R+P, closest 2 first until you feel resistence then the back 2. If the focuser movement feels sticky then remove the R+P screws and remove the focuser barrel. Clean the barrel with metho and give it a good gloss with car wax. Reinstall the barrel and R+P.
Cheers!
Reply With Quote
Reply

Bookmarks


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 05:54 AM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Advertisement
Bintel
Advertisement