Edit: Okey I found out how fast a stepper can turn and it seems like it can go over 2000rpm, but I wont expect more then 500 as it's quite big. This will give me about 40IPM. Thats enough for me and I can still keep it as accurate as I want it to be.

The rest of the post is now useless! Feel free to delete the whole thing.

First post here, so I might ask some questions that have been asked before, but I have done a lot of searching and I can't really find what I'm looking for.

First of all. How fast can a stepper rotate? (steps per second or rpm). I have seen some that can go 12000 steps per second, but they were only 300oz-in motors and I'm going to use a 1160oz-in motor (which is slower). If 12000 is as fast as a stepper can go, then I will end up having a really slow machine.

I want accuracy, but I don't really know how accurate its worth making the machine. I was thinking that one step = 0.01mm (ca 0.0004"). Now for some simple calculations: 12000 steps / min * 0.01 = 120mm / min = 2mm / sec. This is slow! It's as fast as the machine will go and I'm not happy about it.

Now do you think that 0.01mm is a bit "overkill"? Maybe 0.05mm is better? When making arches will you notice a big difference between 0.01 and 0.05?

I work with machines every day (CNC and manual) and all of them work between 0.001 and 0.005mm which is a lot finer then I'm planning, but then again these machines are way more sturdy and of higher quality.

So! To make it short! How fine does the resolution (step / mm) have to be to make a nice smooth hole?

Oh and can someone tell me how fast their stepper motor can turn?

PS. If this topic doesnt belong here, feel free to move it. I just thought it fit here becaose it involves mechanical calculations and feed screws.

I wait with you for some answers....:cool: