I'm making something that's essentially like one of those old hypnotist discs, like this:



I was wondering if anyone has any advice for a small motor that could spin it at variable RPM from about 1 rpm up to maybe 60 rpm. I'm interested both in something very simple that could be controlled by a pot, and/or one that could be controlled by an ESP32/Arduino.

Will be spinning a lightweight piece of plexiglass or plywood.

Thanks for any help.

 

To get that sort of control, I'd go with a small stepper motor.
Mayne even one of these from Ebay...

One of these as it has 64:1 gearbox reduction, and a driver board that an Arduino or similar cad drive.

 

Awesome, thank you. Any idea on how quiet that would be?

(And for anyone else coming this way, that's the 28BYJ-48).

 

I have a motor drive from an old CD player. In particular the motor that slews the laser back and forth. When powered at 3.3VDC it spins the final gear at about 2 RPS (Rev's Per Second) or (120 RPM). Using some old tape deck pulleys you can also gear down the rotation rate. All scrap from an old stereo.

I have a lot of junk. In fact, I made a marble machine out of the motor and worm gear drive that rotated the 3-disk disk changer. Its rotation rate is about 1 RPS (60 RPM).

Instead of using plexiglass or plywood, a foam board would be much lighter and a whole lot easier on any bearings you scrape together. The shaft that drives the cassette tape past the tape head is a pretty robust shaft and bearing set.

 

You might consider a gear head DC motor like one of many by Pololu, 100 RPM@ 6V, 70 mA. Easy
speed control with pot and transistor or a PWM controller @ about US $5.75.
Selection depends on your location.
Another choice from All Electronics, 6-24 V, 142 RPM, dual ball bearing, smooth, quiet operation, 6 mm X 14 mm shaft with extended motor shaft for tac .

 

You might consider a gear head DC motor like one of many by Pololu, 100 RPM@ 6V, 70 mA. Easy
speed control with pot and transistor or a PWM controller @ about US $5.75.
Selection depends on your location.
Another choice from All Electronics, 6-24 V, 142 RPM, dual ball bearing, smooth, quiet operation, 6 mm X 14 mm shaft with extended motor shaft for tac .

Thanks. In the case of the 6-24 V motor (link), how would I connect a disc to it? Would I need to purchase a coupler for it?

And any tips on controlling its speed?

In final form I plan to laser cut a plexiglass circle with a hole in the center for the shaft. Possibly also 1/4" (6.4mm) plywood.

 

Do a Google search from display motors. These are motors used in animated store displays. Hankscraft is one popular manufacturer, with a selection of speeds. But there are other manufacturers.

To vary their speed, look at PWM motor driver modules.

 

For the plywood I would drill with a # 1 bit and force onto shaft or epoxy either disc on to a EU
set screw 6 mm pot. knob. Or dug into spacer bin for a brass 3/16 ID, 1/2 " OD X 1/2 " L & drill out to 6 mm, solder to a brass disc.
Where are you located?
I also made some knobs from 1/2 " plastic with set screws, bolt or glue.

 

Thanks, those display motors look really interesting. Hankscraft has some really nice looking motors.

I got a 28byj-48 wired up, it's great. Very quiet, nice and small, plenty of torque. I'll be using these for lots of things. It's a touch slow (max 15 rpm) for this particular application though, which is basically this:

I think that's about 60 to 120 rpm. Does anyone know of a similar motor that spins at or close to that speed? It wouldn't need a lot of torque, my disc will be very light.