Modded SW Focuser for MAK (Updated thread)

[04Stefan07]

I have been trying to adapt a SW focuser I have to my MAK but it is difficult as it isn't designed for it. It's hard looking for some parts.

Does anyone know any focusers for these telescopes?

[Astro_Bot]

No, but I used to have an 8" Saxon Mak-Cass with SW focusser. It was attached with a DIY right-angle bracket screwed to the back plate - only way to get it to fit. It worked well enough.

[g__day]

For $129 I put a Bintel Crayford 10:1 fine focuser on the back of my Skywather 127mm MAK and used it for fine focusing. To use this So roughly move the mirror to focus with the normal focus knob - then never used it again - only use the Crayford focuser.

To do this needed a tube adapter from memory from the USA (tp change teh 48mm back to a 2" back) and a spacer (one simple nylon zip tie).

Now if I could do this with a manual SCT focuser - stands to reason you could put either a motorised standalone or PC controllable fine focuser in its place.

A Moonlight SCT focuser would most likely be great, alternatively you used a normal Crayford SCT focuser (Bintel ~ $130) add a JMI focuser (Bintel ~ $245) then make it PC controlable by adding a Shoestring astronomy FCUSB. http://www.store.shoestringastronomy.com/images/fcusb.jpg

I did this with a C9.25 - first added a 10:1 Starizone fine focuser for improved manual focusing (also reduced mirror shift) then added a Meade motorised Zero shift focuser and ran this through a ShoeString Astronomy USB Focus Controller.

From memory Starizon sold the collar need to change the Skywatcher's rear thread to allow 2" normal Crayford or Meade focusers to be attached. I recall it converted the 48mm rear to a 2" tube http://starizona.com/acb/M48-to-2-Adapter-P3579C109.aspx


Personally I'd advise get the matting collar you need and then use Moonlites High Res Stepper Motor with MoonLite Mini V2 Controller - controlled via ASCOM / PC thru USB port and Virtual Serial Port software.

http://www.focuser.com/cgi-bin/dman.cgi?page=motorstepper

I have one of these on a WO FLT 110 and its brilliant! They sell for around US$ 440 plus postage - and are works of art!

[04Stefan07]

I was able to mod with thanks to the link below. I had all the stuff just had to find the rubber band and how to mount it!

http://stargazerslounge.com/topic/76705-sw-electric-focuser-on-127-mak/

It works perfectly! Here is a picture.

I actually learnt that you could remove the focuser knob which I did to experiment but works like with it on as well. I accidentally pushed it in a bit which scared the crap out of me because I thought I broke it but I was able to push the knob in and out. To make sure I took the scope out and tested it and it was fine.

Next tube rings!

[g__day]

Innovative! Do you control it from the PC?

I wanted a 2" back on my MAK originally so I could readily attached DSLRs without vignetting the light path. Wish all scopes used a standard 2" or 3" collar to attach the rear focuser!

[04Stefan07]

Nah just from the hand controller for now.

Will be looking at PC control in the near future.

[PhilTas]

Hi Stefan,

have a look at www.wegatoptical.com and also do a search on Cloudy Nights for ETX125TB and Terabeam.

Some owners on CN have fitted their scopes with focussers.

It might give you some different ideas.

cheers Phil

[04Stefan07]

Thanks Phil.

Well my modded focuser didn't last long. It's promising but I do not like the rubber band part.