Barn door tracker motor

[Tadakun]

anyone have any experience with coupling a motor up to this device? I've read a 1rpm motor is what is needed to couple to the 1/4 - 20 bolt. Where can you find one for sale?

[Moonshane]

I saw some on Ebay that were 1rpm and powered disco balls. not sure if they'd work though.

also maybe a 12v 2rpm motor on ebay but run on 6v? or a 4rpm run on 3v (e.g. 2 x AAs).?

[barkis]

A stepper motor would give more precise control, and a simple crank attached to the motor shaft, and contacting against a pin which is pressed into a drilled hole in the threaded rod.

That arrangement allows a quick rewind of the rod when it has reached the end of it's run.

You could have the motor rewind the rod, if you build the controller to accommodate motor reversal.

Ron.

[Moonshane]

I am seriously going to have to learn about this sort of electronics. seems much more flexible than using the apparently more simple DC motor and PWM controller.

[wayne weedon]

A stepper or even easier a RC servo converted to continuous rotation could be used.

The latter have a well proven gear train inside so produce plenty of torque.

Wayne...

[Davidv]

You might have a job getting one now but I used a stepper motor complete with the electronics PCB from an old 5.25" floppy disk drive. This saved me the job of having to build any circuitry to drive it. I then used a 555 timer IC to drive the PCB to obtain my 1rpm. The whole thing was powered by a laptop battery. It did require a bit of electronics DIY knowledge to cobble it all together but it worked very well. This was back in April 1997 when I took some photos of comet Hale Boppe which I was very pleased with. Dave