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could someone tell me what the ratio would be if i went with 32mm dia and 32mm pitch to achieve 10mm pitch? im guessing 3:1 or am i wrong
edit: also goal is to aim for acceleration rather then speed for 3D work and with the ballscrew being almost 3 meters long and driven with a rotating ballnut would you say 32mm is needed? again acceleration is important here not speed although a decent amount of speed is still required.
thanks
I can't see any information about the software that will control the machine.Its quite normal to have a box in the configuration stage of the machine that will allow you to tell the controller how many steps per millimetre there are.So you need to determine how many (if any) microsteps per revolution there will be and then add the information about the reduction ratio and the thread pitch.I don't really understand why you would want to select 10mm but if that is the necessary amount,wouldn't a 10:32 reduction be appropriate?Or any other multiple of 5:16.I can remember a machine that had 57.33 steps per millimetre and it worked OK.
The motor torque is really the limiting factor. The position resolution is just a matter of steps (or micro-steps) per revolution. My old router had a 40mm x 40mm pitch ball screw with a 1.3:1 timing belt drive reduction. I had the steps/rev set at 0.01mm resolution.
If you are using stepper motors, then you want to run them in the lower end of their RPM range to have maximum torque, and thus maximum acceleration.
Using nema 34 closed loops 10Nm on all 3 axis. Its the pulley ratio and pitch size I'm unsure on too. I was going with 2525 screws with 2:1 but I think 32mm might be best?Quote:
Originally Posted by Jim Dawson
Again on my old router, my cross axis had a 2525 ball screw, and a similar stepper, it had a timing belt drive with a 1:1 ratio. It sounds like you have plenty of torque available, so it's just a matter of setting the steps/rev to your desired resolution. Most important is how much mass you are trying to accelerate, this is your limitation. If you know the mass, you can do the math to calculate the max acceleration with the available torque.Quote:
Originally Posted by reefy86
https://www.linearmotiontips.com/cal...e-ball-screws/
He is planning on using a rotation Nut so not much mass to moveQuote:
Originally Posted by Jim Dawson
So the other moving parts of the system, like the carriage, don't count as moving mass?Quote:
Originally Posted by mactec54
Thank you for playing, please try again.
25mm Ballscrew will be fine if you are using a rotating nut, 32mm is always going to be better but that is a course pitch you have to deal with, you will have to think about what the resolution will be and how smooth you want your machine to runQuote:
Originally Posted by reefy86
Your link you posted is only referring to Ballscrew and Motor torque.Quote:
Originally Posted by Jim Dawson
He would need different information for using a Rotating Ball Nut, not what you posted :)