Advice please : Quick voltage and amps question + speed control

[Fivetide]

How about three steppers

Yeah Clive I have 3 Nema 17 high torque but I wasn't sure if running them constantly for 20 mins would be ok ?

[Clive S]

Yeah Clive I have 3 Nema 17 high torque but I wasn't sure if running them constantly for 20 mins would be ok ?

Nema's can run for hours think router and 3d printers, they can also run very hot in access of 60C without problems.

They also have the better torque at lower speeds

[A_Camera]

Yeah Clive I have 3 Nema 17 high torque but I wasn't sure if running them constantly for 20 mins would be ok ?

Sure it's OK to run them constantly for hours also, but you need a driver for each and a motion controller also. So it is a bit more complicated. Even if you don't want a driver for each motor, just want to connect all three in parallel it is a fair bit more complicated to do what you are showing in the video.

[Clive S]

Sure it's OK to run them constantly for hours also, but you need a driver for each and a motion controller also. So it is a bit more complicated. Even if you don't want a driver for each motor, just want to connect all three in parallel it is a fair bit more complicated to do what you are showing in the video.

Yes But if you had read the other post http://www.mycncuk.com/threads/10360...t-CNC%29/page2 you would have seen that this has be discussed

[magicniner]

and a motion controller also. So it is a bit more complicated.

http://hobbycomponents.com/motor-dri...-motor-drivers

But not very complicated as the above linked product has already been suggested, it's as complex a motion controller as is required, as the occasional lost step isn't an issue one pulse generator could be used for all three drivers - Simples! ;-)

- Nick

[A_Camera]

http://hobbycomponents.com/motor-dri...-motor-drivers

But not very complicated as the above linked product has already been suggested, it's as complex a motion controller as is required, as the occasional lost step isn't an issue one pulse generator could be used for all three drivers - Simples! ;-)

- Nick

True, with that simple controller it is much better than three power drill motors. Also more torque even at slow speed.

[Fivetide]

True, with that simple controller it is much better than three power drill motors. Also more torque even at slow speed.

I have ordered or already have everything for the DC and Stepper builds.
They both have merits :
The stepper build linked to an arduino program will be good for taking the roughed out semi-sphere to an unpolished perfect sphere. I can set the program to speedup gradually and shift the rotational direction. More torque is required because it tends to grab when rough.
But it takes more parts and is a more expensive build. You have to have 3 controllers , flexible adapters and chucks.
The cordless drill version is good for the high speed polishing where torque is not a huge issue, it can also be controlled with an arduino and has a built in gearbox / chuck. Its also a cheaper build, 1 power supply and a single controller. Bit more cooling needed if there is no built in fans.
If .. and I say if ! I get them both working I'll do a vid and some pics.

[A_Camera]

Yes, the stepper solution is a bit more complicated and more expensive. BTW, rotation direction change with a cordless drill motor is very easy, just switch the polarity on the motor you want to change the direction. Looking forward to see the vid.

[Fivetide]

Well it worked , thanks guys, pretty simple in the end with your help..anyway a vid .. sounds like a jet engine taking off lol :)