Gandalf

Acme

110vdc 500w motor ($55) with a 10PI acme thread should be able to accelerate pretty fast. The range seems to be 3000-10000rpm, so I'm not sure how fast it will actually go. But at full speed, even 3000rpm is 5"/s. even assuming it takes 500ms to change direction, that's

I've also seen 4Nm 48v steppers for around $40, that might work.