variable speed lathes

Does anyone have issues with variable speed lathes and the motors burning out ? Just cooked my second in 18 months. Drilling holes of around 15 mm and if it grabs can stall the motor. I did start small 4mm and worked my way up.

Running variable speed motors at slow speed under load for an extended time is a problem as it will overheat. Drilling a 15mm hole requires a lot of torque and a lot of heat is generated by the motor. Also when the motor is running slowly the fan is not running as fast to cool it. An extra fan would help to take away the heat.

I have a similar problem with my old flat belt drive lathe. Even in back gear on the slowest speed pully, the belt will sometimes slip when the drill grabs.

Paul.

I have an ml7 and yes that will stall but the motor while getting hot after a few hours takes the heat but guess it is always running at a constant speed and the pulleys take care of speed so the fan does its job.

Did consider a second fan tonight especially as the motor is tightly encased so air circulation will be poor. Thanks for the info Paul its always good to get another persons thoughts.

I am thinking of rebuilding this lathe and selling it as I have seen a slightly longer bed lathe with better swing and a good speed range via pulleys.

Does anyone have issues with variable speed lathes and the motors burning out ?

There are always exceptions. My lathe motor runs at constant speed, but the lathe spindle speed is infinitely variable between max and min limits. No problem of overheating the motor and no need for electronic speed controllers. Cheapness is not always bestness!

Never stalled my 280 while drilling in the 10 years that I have had it with bits upto 25mm dia. my next size down from that is 3/4" so thats a reasonable amount to be removing in one go. Are your drill bits sharp and how hard are you forcing the drill in?

If I do get a snatch then it's more likely the drill will spin in the chuck

You could try running with alittle less tension in the belt so that acts like a slipper clutch and will give the motor an easier life.

Edited By JasonB on 25/06/2017 07:35:49