if you have a DRILL you have a LATHE

[beam0]

Okay good point that drills are made to drill and not designed for side load pressure, but knowing the abuse I’ve put drills through over the years without ill effects (even cheap ones) I wouldn’t worry too much about wearing out bearings just to grind down a couple of pills, especially aluminum ones, unless you’re going into production. I mean how many pills you going to need to grind like this in a year? We’re not talking about grinding an entire car frame or something like that.

It’s not that I haven’t seen drills that developed bearing play, I have, but it ain’t gonna happen that quick.

[Tom_Tom]

@kiriba-ru

Most AC drills have cheap simistor/tiristor as speed tegulation circuit. As result if you set speed to ~30% you will get ~5% torque. Some modern drills have universal dc motors with more complex speed regulator and dont have torque problem.
Also, today even $30-40 cordless drills have 2 speed gearbox. I dont know all markets but Ive bought cheapest 2-speed bosch drill for near $120, all models below this price had single speed (-》low torque).

I have corded and cordless drills with brushed/commutated motors, which are “universal” except for the speed controllers, i.e. there is no difference between the motor characteristics, whether supplied with AC or DC.

All of mine have true speed controllers, somehow they get feedback from the motor and try to maintain the speed demanded, until they stall. And crank up the torque. Not just a simple thyristor chopper.

All of them have low and direct gears. My big corded one is a Bosch, I think 800 Watts, it is quite a beast. Cordless drills just don’t compare.

Brush-less motors are the latest thing, particularly for battery drills (increased efficiency and durability), and potentially they can do more than a simple “universal” brushed motor, but for amateur applications where durability is not so important, the old brushed motors still do the job.

Nevertheless these things are not designed for continuous operation, internal specs I have seen suggest they are designed for 100 hours operation, which is a lifetime for amateurs but just a year or so for professionals (used as a drill) I wouldn’t think of using my big (green) Bosch to drive e.g. a wood-turning lathe. Even a pro (blue) Bosch would be scrap after a short while.

All that said, a drill, preferably clamped down securely, is a very versatile thing that can do so much more than just drill, with a bit of ingenuity.

[kiriba-ru]

@Tom Tom

i.e. there is no difference between the motor characteristics, whether supplied with AC or DC.

No.
Lets say that for safety turning you need 100rpm (chuck speed) that is near 600rpm motor speed. 600rpm=10 rounds per second.
Battery powered motor will have constant torque. AC powered motor will have 20 torque “pushes” and same quantity of zero-torque points (when rotation continues because of inertia). You can dont feel this difference at high speeds because big torque peaks combined with big inertia provide smooth torque, but at low rpms battery powered drill is times more durable.