What's that!? You want autofocus but don't want to spend a fortune?

[Wyvern]

That's what I said when I was putting my astrophotography rig together.

So after a quick search around, it seemed the the MyFocuserProV2 was by far the most complete of the DIY solutions out there.
I'm not going to reinvent the wheel here and write a full instruction manual as there are already some very thorough resources out there for building your own which I'll list below.

You can find the source code for this project here https://sourceforge.net/projects/arduinoascomfocuserpro2diy/files/ARDUINO%20FIRMWARE/

astro_obrads on youtube has done a great video on how to build and test the focuser.

I used the 8825 stepper driver controller for this and it worked fairly seamlessly, the only slight issue was that when initially powered up, the controller can get very hot if the potentiometer is incorrectly set. This is covered in the video however I would recommend tuning it aniclockwise all the way.

The stepper was a standard NEMA17 but with a 27:1 gearbox similar to the one below

https://www.ebay.co.uk/itm/27-1-Planetary-Gearbox-Nema-17-Stepper-Motor-L-48mm-1-68A-4-Wires-3D-Printer-/392161066191?hash=item5b4e9efccf

The sourceforge link also contains the ascom drivers and an ascom driver tester. I'd recommend testing using the driver tester. You may need tick the Reverse direction check box is the in command moves the focuser out.

There is an extended settings menu where you can configure backlash and step size and more.

I machined a mount from some aluminium flat bar (I think alternatives to this are available but I had it laying around)

This is it mounted on the scope.

Hope this post was useful to someone, any questions let me know.

[Wyvern]

Could a mod kindly change my title to say autofocus. Apparently I can’t proof read. ?

[MarkAR]

Nice job, looks very professional.

[Carastro]

Posted by: @Wyvern

Could a mod kindly change my title to say autofocus. Apparently I can’t proof read. 

? ? ? ? ? ? 

[ChrisWright]

Excellent guide @Wyvern , might strat looking at requirements this weekend I I have a rudimentary HitecAstro DC focusser currently.

 

Will also look into the topic rename for you. Cannot find the way to do it currently!

[ChrisWright]

Ordered all the parts for this which will hopefully arrive tomorrow.

Also changed the title for you @Wyvern

[Stub Mandrel]

I found a TekkyDave one worked well with the tiny geared stepper and very simple to use, but now my imaging rig is too heavy on the scope I want to use it with. A shame as it is so compact.

I will probably move it to a smaller scope and fit a NEMA17 for imaging.