standard synta focuser - what upgrades have you done?

[Fozzie]

Morning all.

I was out with my 200p F5 this week, I've not used it for a while due to baby, house move, work and ultimately favouring the frac..

What I noticed was the focuser is not on a par with the Crayford on the frac, particularly the two ep converters..

I've already added a nice 10:1 upgrade for fine tuning but the two thumb screws to tighten the ep adapters/holders just don't cut it.. in fact I'm not happy withe movement you get from them, especially the 1.25..

What options are there to upgrade this part of the focuser.. not looking to spend a vast amount so no points for recommending moonlights or the like...

Thanks in advance..

Ta

Fozzie

[Dave Lloyd]

There are threads around on stripping and servicing these but I can't seem to find any.

[Fozzie]

Hi Dave, and thanks.. I'd seen the threads and so far I've managed to tighten up the complete unit, install a 10:1 ratio adapter and even flock the draw tube.. The bit I'm interested in are the plastic adaptors on the end of the draw tube that the ep's are held in.. The 1.25 adaptor is just wobbly on the two thumb screws..

I know that baader do click stop adapters and there are things called parralizers etc.. but I'm at a loss for which one..?

Any thoughts anyone?

[Fozzie]

It's these plastic bits that are the end of the draw tube ep holders I'm looking g to improve..

[russ.will]

When I had the SW focusers, I managed to get hold of something like the forth item down on this page, to convert the draw tube to a standard 2" fitting.

I also had one of the generic 2" ED Barlows that go for about £50. When you unscrewed the nose piece off the Barlow, you were effectively left with an extension tube, complete with it's own 2-1.25" adaptor, which you just leave in the focuser, full time. At a stroke, you have a focuser that now behaves like a normal focuser with no faffing about with extension tubes and a half decent 2x Barlow for all of your EPs.

I think I picked up both the adaptor and the ED Barlow second hand for about £50 all in.

In retrospect, it wouldn't have cost much more (when you consider your 10:1 focuser knob) just to buy a decent TS Newtonian focuser, but as you already have the knob, it's worthy of consideration.

Russell

[Fozzie]

Thanks Russ, that might be just the ticket...

It's the "wiggle" that you get from the two thumb screws rather than a compression ring..

I'm going to pinch the 2" to 1.25" adapter that's spare from the starwave frac as I have a two inch diagonal with reducer too.. I think this should reduce the wiggle and hopefully still achieve focus... Ideally I'd like to use a baader click lock adapter but removing the skywatcher section must add 50mm to the focal path.. Need to see if I've enough outward travel..

Thanks again..

Fozzie

[russ.will]

Fozzie, just check the internal diametre of the female thread on the SW draw tube. I seem to recall there might be two different diametres out there, although one may be historical. 

As far as adding the required extension, I also used the Altair/GSO self centering adaptors, which are quite a lot cheaper than my original solution, unless you want a 2" Barlow. They're not quite Baader Quicklock as they need a turn or two to go from secure to release, but they do self center very nicely and come in a useful range of lengths - I think I was using the 50mm one. I also use the SC 2"-1.25" adaptors and because they're so cheap, leave some permanently attached to 1.25" accessories like my Binoviewer, to save faffing about.

Russell