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How to adjust fine focus on W/O 90mm?

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11 replies to this topic

#1 CHASLX200

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Posted 22 July 2019 - 06:14 AM

My fine focus stopped working and no clue how you adjust it. Normal focus is fine. 



#2 junomike

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Posted 22 July 2019 - 07:34 AM

Should be a small set screw on the underside of the fine focus knob.  Tightening it should fix things (usually).

See pg 7 (frame # 8).



#3 CHASLX200

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Posted 22 July 2019 - 07:59 AM

My focuser is nothing like that one with all the small screws.



#4 gezak22

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Posted 22 July 2019 - 08:39 AM

My focuser is nothing like that one with all the small screws.

So post a picture?



#5 WilburTWildcat

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Posted 22 July 2019 - 09:48 AM

Should be a small set screw on the underside of the fine focus knob. Tightening it should fix things (usually).
See pg 7 (frame # 8).

That's what my focuser looks like. My fine focuser rod was a bit bent, so I took off the knob to inspect. Ended up replacing the focuser; the fine foxus knob wobble didn't matter, but it just couldn't hold my heavy eyepieces.

Shameless self promo to OP: I have a replacement focuser to sell you.

#6 CHASLX200

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Posted 22 July 2019 - 09:52 AM

9igxgh.jpg

 

I never use fine focus anyways. But the buyer would want it working i am sure as i am selling it.


Edited by CHASLX200, 22 July 2019 - 10:03 AM.


#7 ris242

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Posted 22 July 2019 - 01:09 PM

Does the fine focus knob have a hole somewhere on it on the outer diameter?

if so, keep rotating till you sight a grubscrew down the hole and tighten it with an Allen key.

i think I had to loosen and adjust the main knob to properly locate mine.

 

i had the same issue when I bought my megrez 88 and tightening the grub screw got it all working as it should.



#8 CHASLX200

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Posted 22 July 2019 - 05:54 PM

I will have to look.



#9 dscarpa

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Posted 22 July 2019 - 06:24 PM

 Something similar on my WO ZS110 a grub screw in a hole. It's a pain to adjust and the WO Crayford on my C9.25 is even worse.  I can't get the fine focus to work on the upstroke on either. Thankfully coarse focus is so smooth on both it's not needed.  David


Edited by dscarpa, 22 July 2019 - 06:28 PM.


#10 CHASLX200

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Posted 22 July 2019 - 06:26 PM

 Something similar on my WO ZS110. It's a pain to adjust and the WO Crayford on my C9.25 is even worse.  I've can't get the fine focus to work on the upstroke on either. Thankfully coarse focus is so smooth on both it's not needed.  David

I can live without it, but a buyer will want to know about it.



#11 junomike

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Posted 22 July 2019 - 11:00 PM

My focuser is nothing like that one with all the small screws.

Looks the same to me.

Check out page 1 (PO1) and you'll see the fine focus knob has a grub/set screw that most likely needs tightening.



#12 CHASLX200

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Posted 23 July 2019 - 05:10 AM

Not the same at all. Look at the two green circles as that focuser has many more small screws.  But overall it is the same minus the extra screws.  When i turn the gold knob it turns the rest of the focuser, but the draw tube does not move.




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