Gemini EAF mount for Skywatcher Skymax 127 or SCT or any Telescope actually

The system is based on a double helical focuser like this:

High Precision 1.25" Double Helical Focuser with Brass Compression Ring M42 T2 SCT Thread 2" Adapter for Astronomical Telescope

https://www.aliexpress.com/item/1005007015547980.html?spm=a2g0o.order_list.order_list_main.130.4e851802XdgCPI

(SCT inner screw variant)

You also need an adapter to attach it on the Mak telescope:

EYSDON SCT Male to Mak Female Threads T-Ring Adapter 2"-24TPI Transform to M45.4*1mm Telescope Threads Converter Conversion

https://www.aliexpress.com/item/1005003187513821.html?spm=a2g0o.order_list.order_list_main.205.4e851802XdgCPI

You also need a GT2 pulley with 30 tooth and a 5mm hole, like this :

https://www.aliexpress.com/item/32880112920.html?spm=a2g0o.order_list.order_list_main.115.4e851802XdgCPI

As well as a 300 mm GT2 belt.

All the part are printed in ASA, but PETG may work too. 

Two CHC M4x35  are used for the focuser clamp, with two M4 threaded inserts.

Two CHC M4x12 with two narrow washers are used to attach the Gemini EAF.

You also need three M3x7 button head screws and nuts for the “Spreaders”. (do not tighten them too much, they have a lot of leverage. Being not too tight can also act as a clutch in case you try to go too far with the focuser

I set the EAF to 6000 and the max value to 12000. I installed the belt with the focuser set at half of its travel. One of the indicator is on zero which is useful to check every now and then.

During observation,  I generally set the focuser to 6200. Then I do a coarse focus with the normal focuser knob of the scope, ending by a counterclockwise rotation, to cope with the inherent “mirror flop” of that kind of telescope.

Then I do the fine focus with some software assistance (SharpCap, Nina, Firecapture …)