RE: [CAD_CAM_EDM_DRO] DC motor as replacement for Stepper motor

At 10:24 PM 1/23/02 +0800, you wrote:

>hi! what we're trying to do is a customise lathe machine. we build it from
>scratch. and it must have a computer interface. well it doesn't need to be
>so complicated. What we had in mind is there is a round disk which holds
>the blades then a sort of a piston from above the blade pushes it. so,
>first we need a motor to rotate the blade and still keep track of its
>movement which is possible if we use stepper. next we need a motor which
>will facilitate to the movement of the piston and keep track of the pressure
>exerted through the degree of the stepper, but the thing is if we use a
>stepper at this piston it might push back so we were suggested to use dc
>motor. honestly i don't know how we are going to build this in 3 weeks
>time. were running out of fund and we don't know what really is best to
>use. and it happened that we are trapped in a 3rd world country where in
>ideas like this are put into waste.

You can salvage small easy-to-drive steppers from old 5-1/4" disk drives,
maybe there's a place near you with junk like that. I've seen them for $1
or $2.
The boards should have usable driver chips on them too (but if the
drive failed it was sometimes those that were gone). Really old hard
disk drives had steppers too, more powerful ones. Talking 10-40MB drives
from 15-20 years ago, of about the same size as the 5-1/4" drives.
(8" drives had really nice steppers in them, but I doubt you'll be able
to find them outside of a museum).

Best regards,

Spehro Pefhany --"it's the network..." "The Journey is the reward"
speff@... Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com
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