WO megrez 72 focuser problem?

[scogyrd]

I've just a brand new William Optics Megrez 72 Doublet APO DDG Telescope and the focuser on it seems to be very coarse and stiff in places (when compared to my 200p focuser) and it makes a sort of squeaking/scraping noise when I turn it. So I was wondering if this was normal (I doubt it) or should I send it back? Or is there a quick fix I can do?

I've not used a dual speed focuser before so I'm a bit confused as to whether they're all like it, although I can't imagine they would be.

[johnrt]

There is a screw on the underside of the focuser in the center, you will need an allen key, it may require slackening off just a touch.

This sort of thing shouldn't get past any decent form of quality control.

[scogyrd]

There is a screw on the underside of the focuser in the center, you will need an allen key, it may require slackening off just a touch.

This sort of thing shouldn't get past any decent form of quality control.

I should've mentioned that I've already tried this and it didn't make any difference to the coarseness. It stopped the drawtube from moving so it obviously did something but it didn't fix the problem.

Thank you for helping anyway.

[scogyrd]

I've just found this page (isn't it funny how you never find the solutions before you start a thread?) -

http://stargazerslounge.com/equipment-help/101848-wo-megrez-72fd.html

And I think this might be my problem.

However, I can't find the two grub-screws on the underside (I presume this fix is for the old focuser?) and I'm too scared to take it to bits in case I break anything so does anybody know how to do this to my focuser?

[FLO]

Megrez-72 are normally set so they work out-of-the-box, requiring only a slight adjustment if you are fitting a heavier than average load. If you have only just received one and it needs significant adjustment you should be contacting your supplier.

HTH

[scogyrd]

Megrez-72 are normally set so they work out-of-the-box, requiring only a slight adjustment if you are fitting a heavier than average load. If you have only just received one and it needs significant adjustment you should be contacting your supplier.

HTH

I thought as much.I was just hoping there might've been an easy fix to save the hassle of having them collected etc..

Thanks for your advice.

[carastro]

It's the central hole between the focus knobs on the back. A small Hex key fits it. Sounds like you've tightened it instead of loosened it.

Should have been right from the outset, but can understand you not wanting the hassle if it's a quick fix. Make sure you don;t loosen it too much though, I had a Megrez and the drawtube used to slip and I'd loose focus. A chum of mine tightened it up (as I didn;t have the right hex key, and it then scraped as he had done it up a bit too tight.

I have a picture of the appropriate hole if you're still doubtful but it's on my other computer. PM me if you need it.

Carole

[scogyrd]

It's the central hole between the focus knobs on the back. A small Hex key fits it. Sounds like you've tightened it instead of loosened it.

Should have been right from the outset, but can understand you not wanting the hassle if it's a quick fix. Make sure you don;t loosen it too much though, I had a Megrez and the drawtube used to slip and I'd loose focus. A chum of mine tightened it up (as I didn;t have the right hex key, and it then scraped as he had done it up a bit too tight.

I have a picture of the appropriate hole if you're still doubtful but it's on my other computer. PM me if you need it.

Carole

Unfortunately I have tightened and loosened the screw you're talking about and it didn't make much difference. That's to say that the focuser still felt very stiff and made a scraping noise, not that tightening the screw up and loosening it didnt do what it was meant to, which is why I think it must be something else that's causing the problem.

Is your focuser silent? If so I think there must be something up with mine and I'll ring where I got it from tomorrow to see what they say.

[shaunster]

Are you sure the lock isnt on? There is a silver thumbscrew on the bottom of the focuser that locks its position, it would make moving it very stiff..

[scogyrd]

Are you sure the lock isnt on? There is a silver thumbscrew on the bottom of the focuser that locks its position, it would make moving it very stiff..

Yes. I've undone that too.

I'm afraid I've just been sold a dodgy one.

[brantuk]

There's an allen key grub screw dead central behind the knurled locking thumb screw underneath. I found it was a question of balancing the two up to get a satisfactory and smooth movement.

Of course you will have to lock off the thumb screw once focused if you load it up with camera gear

[Moonshane]

although not the same focuser, I found what really helped with mine (which is the SW type) was to loosen the four small silver bolts in the central area and then tighten the two larger black ones either side of the central tensioner bolt. this arrangement of 6 bolts seems to act as a push / pull system to get the overall tension correct.

worth a try but I know what you mean about fiddling with new gear.

[scogyrd]

It still makes a scraping noise and feels very coarse if I undo both the allen key and the lock so I don't think it is either of them that is causing the problem. It does sound to me like the noise is coming from inside the gearing but it's hard to tell.

Is your focuser silent?

[Moonshane]

not quite and there is a slight issue with it (I may be able to sort this out with loosening the locking ring I think when I can be bothered to take it apart) but as mine was used I am more inclined to accept it and just use it. generally the focuser is acceptable and works well enough for the purpose I got it for so I am happy. it holds the 2" diagonal and my 26mm Nagler so at least it's got enough grip.

[scogyrd]

although not the same focuser, I found what really helped with mine (which is the SW type) was to loosen the four small silver bolts in the central area and then tighten the two larger black ones either side of the central tensioner bolt. this arrangement of 6 bolts seems to act as a push / pull system to get the overall tension correct.

worth a try but I know what you mean about fiddling with new gear.

I did think about trying this and I might well have a go in the morning, when it's a bit lighter so I don't lose anything. I have a bad habit of losing bits of telescopes when I take them to bits:D. Which is why I'm a bit reluctant to take it to bits, besides which, you shouldn't have to take things to bits that cost nearly £400 just to get them to work properly imo.

[Moonshane]

I agree matey

good luck and hope you get sorted either way.

[carastro]

Deinitely doesn't sound right, and if it's new I would get on to the retailers. No mine wasn't noisy until my chum did it up too tight.

Carole

[scogyrd]

I've just rang the shop up and they're sending me a replacement out so thanks for your help everyone, it was much appreciated.

[ollypenrice]

All this goes to show that the current craze for metal roller on metal drawtube Crayfords is as unsatisfactory as you'd expect it to be when thinking about it.

The exact tension required has to be found and maintained across a range of temperatures and in humid or dry conditions. The whole idea is fundamentally flawed. I'm certain that in the fairly near future there will be a big push amongst manufacturers announcing that their new model has a proper rack and pinion focuser...

Olly

[scogyrd]

All this goes to show that the current craze for metal roller on metal drawtube Crayfords is as unsatisfactory as you'd expect it to be when thinking about it.

The exact tension required has to be found and maintained across a range of temperatures and in humid or dry conditions. The whole idea is fundamentally flawed. I'm certain that in the fairly near future there will be a big push amongst manufacturers announcing that their new model has a proper rack and pinion focuser...

Olly

I don't think it was a problem with the design of the focuser, although I've not used a working one yet so I can't really comment on it. The problem was that they sent me a scope with a faulty gear system, which just means that William Optics quality control isn't up to much as the scope should never have left the factory...