SW Equinox 80 focuser problem

[MjrTom]

Hello,

I have been loitering around the forum for a few months now but this is my first thread.

As the title suggests my SW Equinox 80 has developed a focuser issue.

currently the draw tube is sticking at part of the movement and also some worrying gouge marks have been developing over the last few months since tightening up the focuser to account for the weight of attached equipment.

I have attached an image showing part of the problem.

On closer inspection it looks like the draw tube is no longer centred in the focuser.

My understanding is that the draw tube is held in place by two bearings and the third point which is the friction plate.

Am I right to assume that the bearing has gone? Is is fixable or terminal?

Pretty new to all this so not tried to fix it other than messing about with the tension grub screw which makes no difference.

If you could cast your thoughts that would be great!

[Dave]

Ouch! I just could not get mine to hold focus with my heavy camera, but I didn't want to over-tighten the two adjusters I knew about.

Then someone on SGL mentioned a third adjusting screw they found.

The third adjusting screw is located mid-way between the focussing knobs on the bottom of the tube?

It sounds like you haven't found or tightened this up alongside the top two.

It would mean you wouldn't have to have the other two quite so tight, which would cause this problem.

Dave

[MjrTom]

Thanks Eagleseye :-)

Well in my haste to find the problem I stripped down the focuser.

It would appear that two of the screws holding the bearings on that side were loose. I have tightened these up and reassembled the focuser however I need to teak alignment it would seem as it is a bit squeaky now when moving the drawtube in and out. I suspect I shall also have to add some grease to the bearings.

It feels as if the drawtube is not perfectly aligned in the focuser.

[MjrTom]

Here is a photo of the focuser stripped down with the bearings visible which seem to be causing the issue.

I have looked at all the screws present and there only seems to be the one grub screw for adjusting the tension of the drawtube.

I dont suppose anyone is aware of any tutorials for tweaking skywatcher/synta crayfords?

[MjrTom]

Anyone know of any good tutorials on how to service a crayford focuser?

Currently it is working however it does have an annoying squeak when moving the drawtube fully in.

What type of grease should I be using on the bearings?

Thanks

Mark

[MjrTom]

Hello,

I thought I would provide an update on the troubles I have been having with this Crayford Focuser...

Since me dismantiling it a couple of months back ago the squeek has started again.

Listening to it it sounds like the drawtube has been compressed slightly and is catching on the bearings.

I finally had enough of trying to fix the problem so this morning I ordered a replacement focuser for it in the form of the Moonlite Crayford from FLO this morning so hopefully should be here in a couple of days.

First Light Optics - MoonLite CF Crayford Focuser for Refractors

I decided since I cant make my mind up which new scope I am going to get I thought I would pimp up my current ED80 before I go on holiday to a truely dark sky with it next month. (west coast of Ireland)

Also it will put this scope in a better position for astro imaging again come winter time focuser droop was such a pain last year with a DSLR & a field flattener and such hanging off the back of it

[swag72]

Good choice Mark. I had issues with my focuser on my 120ED and upgraded to a moonlite. Apart from the focuser being beautiful (!) it has sorted out my focuser sag that I was getting with the DSLR. You've made the right decision, or have you - What colour have you got?!!

[MjrTom]

Haha I did have to think about it for a while...

I went for Black, It fits with the current paint job a lot better, along with the black tripod and Alt/Az mount and also black RDF so it my stealth ninja scope lol

The Equinox 80 is a really nice scope optically let down by a very average quality Crayford. I suspect that during last years imaging runs I over tightened the focuser which bent the tube out of shape a little so partly my fault I guess.

[MjrTom]

oops double post