variable speed dc drive

[DragnsBane]

I am in the process of building the Gingery series of lathes and would like to add a variable speed dc drive. However, I can't find one for a decent price, so can anyone tell me how to build one or direct me to a good schematic. Any help would be greatly appreciated.

[Al_The_Man]

Motorola MC33030 http://www.datasheetarchive.com/data...11/118509.html
see fig 30 for amplified version.
Also you will need the DC power supply suitable for the motor you are using.
Al

[JRoque]

I have a couple of these and they're very good: http://www.surpluscenter.com/item.as...tname=electric

Check the same site for $20 DC motors @2.5HP good for the controller above.

Regards,
JR

[ViperTX]

DragnsBane,
Do you know alot about electronics? If you don't then you'd be better off buying a DC motor controller from someone like Granger and using a treadmill surplus motor. Ebay ocassionally has a guy selling a treadmill motor with speed controller for under $200.

I can hear the questions.....what size of transistor do I need for driving a 1 HP motor.....darn these are expensive, where can I get them cheaper.....how do you cool these....and of course we'll be advising you that you need MOSFETS.....and there goes another series of questions.....so, how long do you want to experiment with new ways to make smoke?

[TinkerDJ]

DragnsBane how far are you into your lathe. I have about 90% of my castings done and my main bed done. I agree with everyone on this one buying a treadmill controller and a treadmill dc motor is the way to go. On ebay there is atleast 2 or 3 right now for controllers around 30 dollars and motors for 20. Can't really compete with the quality that the surplus controllers have. And in the end unless you have a really good assortment of electronics bits to make one then it will cost you more to build then to buy surplus.

[DragnsBane]

JRoque,
Thanks for the info on the Miniark controllers. I looked at them before and didn't think to much of them. But they should be worth a shot.

ViperTX,
I actually do know quite a bit about electronics and what I don't know I can easily look up in the 20 odd text books I have on the subject. The question I pose to you is why should someone build a stepper motor board when you can buy on already made?

Al the Man,
Thanks for the link. I should be able to get something going off of it.

TinkerDJ,
I rammed up some molds for the lathe and haven't got much further than that. I was going to cast it out of aluminum then decided to round up the materials to make my own ZA-12. It has them same properties as cast iron but melts around 930 F. Staill need to round up some more zinc. If you need more info on the ZA-12 contact me PM me with your e-mail and I'll send it to you.