I'm need help to choose the right motor for a mechanical project, and would be very grateful for recommendations.Requirements:1) Cheap - ideally something I can get used on eBay or cannibalize a machine for.2) Variable speed - approx 10rpm to 600rpm, running off a 12 amp Variac (Staco Energy Products Model 3PN1210B Variable Autotransformer)3) High torque, especially at the bottom of the speed range4) Ideally not too noisy, but size is not a problem - up to about 18quot; x 12quot; x 12quot; will workDo I need a DC motor and then put a rectifier and/or step down transformer on the Variac? Or is there an AC motor that will fit the bill for under a hundred bucks?How do things like single phase or three phase motors affect my choices?What else do I need to think about Thanks in advance for any advice.
You need to select a motor based on the torque and speed requirement you have, and whether it needs to variable speed. For low power applications, DC is best.
VERY SIMPLE, BUY ANY LARGE SIZE AC POWER HAND DRILL THAT COMES WITH VARIABLE SPEED CONTROL.
The best thing to think about is how many pounds-feet (or Newton-meters) of torque do you need. High torque is not a useful description. Edit 1 addition A corded, variable-speed, 1/2 inch chuck, hand-held drill could provide almost as much torque as the 1 Hp DC motor and pulley arrangement described above. It can probably be bought new for less than the DC motor. You can probably get one at a pawn shop for a lot less.
