Forestbird Originals submitted a new resource: 3D Printed Hand Wheel for Openbuilds 8mm Tension Nut - 3D Printed Hand Wheel for Openbuilds 8mm Acme Leadscrew Tension Nut Read more about this resource...
Do you find you need to retension the screw every now and then or is it for a one time tension and then it is removed?
This actually isn’t specifically for tensioning, this is used on top of the tension nut after tensioning specifically for manually jogging the machine by hand. I found that it was useful while building my machine to get the 2 axis aligned at 0 and for moving it if it got out of alignment It is your choice whether you want to keep it on the machine or not
Careful, turning stepper motors by hand turns them into generators, backfeeding the stepper drivers, and can damage the drivers
Yes you are correct. These were designed for correcting out of squareness that happens over time. Since the Y motors are linked in software, this would have to be done by hand. Damage is only done if you move them too fast, which is almost impossible with a handwheel and lead screw. This is mostly for regularly fixing out of squareness that happens. This is a very common setup for leadscrew designs. You are not wrong though, if you crank them really fast you could generate enough back voltage to damage the drivers. More than likely you couldn't turn them synchronous enough with 2 hands to prevent it from locking up due it becoming skewed and jamming up.
I think you underestimating the voltage generation a bit, Tim, but the best way to verify it is to hook up a volt meter to any pair of the motor wires and crank it. If you happen to do it, please post it since I'm curious too to know the exact amount.
Multimeters "average" so short pulses look lower. Oscilloscope rather. Remind me on Monday, i can actually set that up. Would make a cool demonstration
If my Y axes are out of sync, I just tweak (turn) one of the Y flexible couplings to correct it - power off and motor disconnected obviously.
Please do. I would be interested to know how much voltage\Amps are generated. I move mine less than an inch in most cases. Ill just undo my aviation connectors if I have to. But it seems crazy when I do this all the time on my 3d printer with larger NEMA 17's and move it 2 or 3 inches at faster paces than this handwheel could do with a motivated person.
Power off should be obvious, I wouldnt square a machine with it on unless I had 2 endstops to do it for me.