Focus pro2 for Stella Lyra

[IDM]

Hi,

I have successfully been using Focus pro2 with a  28BYV on my Tal 100 refractor fir months. Recently I bought an 8 inch Stella Lyra and it really needs an electronic focuser to get really good planetary photos.  However, the focuser is so stiff I cannot find an easy way to get the stepper to work with it. On the Tal I directly coupled the motor by removing one of the  focuser knobs (this worked really well). When I did the same to the Stella Lyra I couldn't get it to work. Has anybody got any good ideas on how to do this or indeed has anybody actually done it with this telescope? Alternatively is there a way of reducing the friction without losing the ability of the focuser to move? I am grateful for any ideas.

 

Thanks,

Ian

[johninderby]

I simply replaced the stock focuser with a Baader Steeltrack RT focuser. The stock focuser should be capable of smoother movement thuogh  if properly adjusted but will never be a Steeltrack.

Edited October 28, 2021 by johninderby

[callisto]

1 hour ago, johninderby said:

I simply replaced the stock focuser with a Baader Steeltrack RT focuser. The stock focuser should be capable of smoother movement thuogh  if properly adjusted but will never be a Steeltrack.

John, I really wish you would stop showing pictures of your Steeltrack...Temptation is getting to much to bare now 😂

[IDM]

Following upon my original post highlighting the issues I had getting my Stella Lyra 8 inch classical cassegrain to work with my 28BYV stepper motor, I have now rebuilt the focuser using a Nema 14 stepper with somewhat increased torque. As with all my projects I tend to work on a geological timescale where everything takes me an age. However,  I am really pleased how the build came together and you can see how it got it all fitted together in the photos below. I used hexagonal PCB  stand-offs (filed to fir the recessed holes in the bottom of the standard focuser. These were attached to 4mm thick aluminium bar which holds the boxed motor, I removed the focuser tension set bolt and replaced with a new bolt with allen key fitting. This was far easier to make adjustments (you can see the hole in the aluminium bar to allow access to the tension set bolt.

What I was particularly pleased with was that once I stripped down and rebuilt the focuser with the new motor attached was that the manual focusing course and fine focus knobs were far  than they ever were when I first got the scope. I have absolutely no idea what I did but if feels much smoother.

Ian

[rsarwar]

An alternative solution would be to connect the motor using time belts with some gear reduction.