Fitting Hex focuser 1:10 woes

[Dean Hale]

Hello

I've just purchased the Bresser Messier 1:10 Gear-set for Hex-Focuser (you can see this below) and i'm having major trouble trying to remove the knob using the supplied hex key. It just won't get a grip. I've attached a couple of poor quality photos (cannot get the camera to focus very well) in case anyone has one of these and has any tips on how to get the little devil out. 

https://www.firstlightoptics.com/bresser-telescopes/bresser-messier-1-10-gear-set-for-hex-focuser.html

many thanks

[MarkAR]

Could be the hex key is a fraction undersize. Doesn't take much on the smaller sizes to be useless.

[Dean Hale]

21 minutes ago, MarkAR said:

Could be the hex key is a fraction undersize. Doesn't take much on the smaller sizes to be useless.

Hi I think you maybe right. Amazon seem to have lots of better quality hex keys for a few pounds. Will give that a go. Thank you

[johninderby]

Had no problem with mine but then had the proper hex drivers. Hex key sets from Bahco, Bondhus and Wera are particularily good and not too expensive.

I use hex drivers rather than keys but prefer them although they are a lot more expensive. My small tool set.

Edited August 24, 2020 by johninderby

[Seelive]

Just be careful that your not rounding off the set screw socket otherwise you may never get it out (unfortunately allen keys generally tend to be made out of a harder material than some of the set screws so if it is slightly undersized it will just round out the socket).

[johninderby]

Cheap hex keys that don’t fit tightly is the cause of many hex screws being rounded off. Cheap hex key sets are a false economy.

[Louis D]

Try both metric and non-metric hex keys.  I usually have to try both sets to find one that fits best.

[Dean Hale]

Thanks all for the advice. I’ve ordered some wera keys. Hopefully these will work. 

[Dean Hale]

Does make me think though. I started this in March during lockdown with a skywatcher 130ps and umpteen purchases later - new mount, additional scope, several eyepieces and bits and bobs (I dare not add up how much). I was too tight to spend £20 on a set of Allen keys. 

[Alien 13]

I have frequently chopped the end off some allen keys with a dremil to give a fresh surface and if that didn't work I have bonded the key in position with some gorilla glue.... a sharp twist usually shifts the stubborn hex screw.

Alan

Edited August 24, 2020 by Alien 13

[Pixies]

or try a slightly oversized torx driver bit and tap it in, then unscrew.

[Shimrod]

39 minutes ago, Dean Hale said:

Does make me think though. I started this in March during lockdown with a skywatcher 130ps and umpteen purchases later - new mount, additional scope, several eyepieces and bits and bobs (I dare not add up how much). I was too tight to spend £20 on a set of Allen keys. 

If you find that it is too late and the hex socket is now a round socket,  I can recommend a set of these:  Damaged screw extractor I had to buy a set to remove the focuser from my 80ed after the screws were fastened in too tight and the heads just stripped. 

[Dean Hale]

Tried the new hex keys and no luck. One suggestion (not here) recommended removing the 4 bolts holding the barrel to the focuser  so I could get a better grip and seeing the bodge job when removed I emailed bresser for advice and they kindly offered to repair the focuser and install the gear set for free. Which is good news and great service. So hopefully a week or two and all will be well.

Edited August 25, 2020 by Dean Hale

[johninderby]

Bresser does have great customer service. 👍🏻

Oh well at least you have a set of decent hex keys now. 😁

Edited August 25, 2020 by johninderby

[Dean Hale]

Finally fixed.
Bresser customer services were excellent - free postage for the repair and it actually looks like they replaced the whole unit in addition to adding the 1:10 focuser. Silky smooth. Unfortunately Will be a few days though until any clear skies are forecast here.

[johninderby]

Glad it got sorted. First class customer service from Bresser again. Gives you confidence to buy from them. 👍🏻👍🏻👍🏻

[Rob]

@Dean HaleGlad you have this fixed. I had (and still have an issue). I bought the 1:10 upgrade and it kinda works when it wants too. I now have that stuck on there due to the grub looking similar to yours.. I know what needs to be done, which is further grease needs to be applied in the 1:10 knob itself, but it also has a rounded grub in the black 1:10 knob, so I can't remove it!.. needless to say I've just ordered some allen drivers. 

I have had the focuser out expose the shaft (like you had done). Did you note the bearings that hold the shaft?.. I'm wondering if they will tap out?.. I want to remove the shaft fully to work with it on the bench. did you notice if this so?.

Thanks Rob

Edited October 1, 2020 by Rob

[johninderby]

One thing I’ve found is that you mustn’t overtighten the new little grub screw that goes on the top. Too loose and the fine focus doesn’t work but too tight and the main knob won’t turn properly.

Edited October 1, 2020 by johninderby

[Rob]

3 minutes ago, johninderby said:

One thing I’ve found is that you mustn’t overtighten the new little grub screw that goes on the top. Too loose and the fine focus doesn’t work but too tight and the main knob won’t turn properly.

Thanks @johninderby I must admit I didn't look at that, just the worn rounded grub that holds the 1:10 on the shaft. Guess I've just been concentrating on full removal!.

Rob

[johninderby]

Quite a few forget to install the new grubscrew in the first place and wonder why the fine focus doesn’t work at all. 

Just fitted one to my new Bresser 127L yesterday and it’s working perfectly. 👍🏻

Edited October 1, 2020 by johninderby

[Rob]

To be fair I don't think I have that grub screw?!!.. I will check later. I just don't recall seeing it in the kit from Telescope house back in 2018. I had no instructions sent with it either!!. I had to call them and they claimed "push on and tighten the grub!.

I'm always the one that questions why I have something left over. 

[johninderby]

There was a tiny plastic bag with the grubscrew in the bottom of the box. Easily overlooked.

[johninderby]

The instructions aren’t the clearest. 🙁

[Dean Hale]

2 hours ago, Rob said:

@Dean HaleGlad you have this fixed. I had (and still have an issue). I bought the 1:10 upgrade and it kinda works when it wants too. I now have that stuck on there due to the grub looking similar to yours.. I know what needs to be done, which is further grease needs to be applied in the 1:10 knob itself, but it also has a rounded grub in the black 1:10 knob, so I can't remove it!.. needless to say I've just ordered some allen drivers. 

I have had the focuser out expose the shaft (like you had done). Did you note the bearings that hold the shaft?.. I'm wondering if they will tap out?.. I want to remove the shaft fully to work with it on the bench. did you notice if this so?.

Thanks Rob

Hi Rob, Sorry i can't recall and couldn't advise on the bearing and tapping out. Hopefully the Grub screw is the issue that as been mentioned. Good luck.

[HollyHound]

I've finally got round to fitting the 1:10 fine focuser on my 10" Bresser dob... huge thanks to all on this thread, as the instructions are really not the best at all and it was a lot more fiddly than I thought it would be... especially realising there are two main grub screws that need removing and then two on the new focuser knob that need tightening (the instructions don't show this very clearly!).

Also @johninderby is spot on, you need to get that small new grubscrew tightening to just the right amount... too much and the main focuser knob is sticky and difficult to move, too loose and the fine focuser doesn't operate at all... eventually just nipped it to the right amount and it now works perfectly 👍

Edited November 13, 2020 by HollyHound