Choosing a stepper motor for Samyangs 135MM

[WbRaDy]

I intend to join the ranks of the wider-fielders with a Samyang 135mm and zwo 1600 with filter wheel and was hoping for some advice on a stepper motor for the autofocuser?, im using a Nema17 27-1 plantery at the moment to shift the camera and filter gear on an ED80 and it works very well but feel its a bit overkill for the above so looking for something a bit smaller and without having to strip down what's already set up, im hearing the Samyangs focus wheel is a bit stiff so trying to take this into consideration but as its only moving the focus i may be able to get away with the smaller versions? 

Thanks

[Dr_Ju_ju]

I'm currently building one for the same purpose, and so re-using the control\driver electronics, so I've gone for a Nema 14 PG27 from OMC Stepper online. They may not have UK stock, but there are usually some in the German warehouse....

[WbRaDy]

Funny enough Julian that was the one i had in mind, and exactly where i purchased the previous motor, just deciding which software route to go, either way i will run it through APT 

[Dr_Ju_ju]

I'm using the MyPocuser Pro  by Robert Brown, https://sourceforge.net/projects/arduinofocuscontrollerpro/files/, (i.e. same as James is currently documenting)

[Gina]

Stiff focussing sleeves on lenses is a bit of a bugbear.  The sleeves on my 200mm f4 lenses are pretty stiff and I might have to modify my ideas.  Currently I use modified 28BYJ-48 gearbox stepper motors with 3D printed quadrant gear and pinion.  Info in my blogs.

[WbRaDy]

Thanks Julian/Gina, i ended up revamping the SW motor i has sitting around, all up and running for test, also thanks Mike "wxsatuser" for the images..

👍

Edited March 21, 2020 by WbRaDy

[Jkulin]

@WbRaDy I like that focusing mod for the 135 and can see many uses for it.

Concerning the connection, is the an RJ9 or RJ45 connection? If so what are you using for your focus control, I'd like to integrate into my Pegasus UPB which has a RJ45 input, is that possible?

Can I ask where you got the belt and drive wheel from?

Many Thanks.