Etch a Sketch style power feed

derf, apologize my ignorance but i am not sure what you are saying.

so I've been researching, how hard is it to replace the lead screws with ball screws?

am i right in understanding that if i took the plunge and moved to CNC i would not use a DRO, and i have to install the ballscrews as they eliminate backlash?

what's the downside to installing ball screws?
 
Much comes down to which mill you have. Some mills have a ballscrew kit and it is easy. Others you would need to buy parts and install without a kit but depending on which mill there might be online examples of what you need and what to do. Also if you have a power feed it may have high resale value if you remove it and sell it for CNC costs. Would not need the power feed.

The CNC software has dro functionality so wouldn’t need a dro.

You don’t have to change to ballscrews but it does help with backlash. Depending on what you are doing backlash wouldn’t matter much. For example etch a sketch type of cutting with careful thought between each cut it would not matter. Running a g code to make a part it does matter.

No real downside to installing ballscrews.
 
Does anyone know how much torque is needed for each axis? Are the big 425 oz steppers required, or can we use shorter, less powerful versions? (Btw I posted this on another one of my threads but realized this is a better place)
 
If you have a choice might want to opt for steppers with a shaft on both sides to make manual use easier, handwheel on the outside.
 
Driveslayer45 said:
Does anyone know how much torque is needed for each axis? Are the big 425 oz steppers required, or can we use shorter, less powerful versions? (Btw I posted this on another one of my threads but realized this is a better place)
Click to expand...

The required torque is determined by what you are cutting (material), how sharp your tools are, and the speeds you hope to achieve. None of those things are "known" so 425 is kind of a good overall starting point as more is better. You could just opt to use smaller motors and wait until you're done building the machine to see if they have enough torque to meet your requirements. The bad thing about steppers is that they don't know when they've stalled long enough to loose steps and therefore be out of position. Weak motors are more prone to loose steps.
 
So I ended up getting a 425 stepper for the x and I 260 stepper for the y (shorter for y so it doesn't stick out so far.

Another question, I'm planning to run direct drive on these, anyone done this or should I setup pulleys (2:1 or 3:1) to change the gearing?
 
ok, i have the first iteration working for powerfeed on the X and Y without sacrificing manual operations.. i have a controller for computer connectivity as well but not ready to try that yet. excuse the pics, the macWIN_20190723_21_25_01_Pro.jpgWIN_20190723_21_25_24_Pro.jpghine just got finished building the mounts. i still need to build permanent boxes for the controllers.
 
I'll bet it sure helped having a mill to build those:), nice work.
 
yes sir it sure did, thanks. as i mentioned i still need to clean up. the only modification to the mill was cutting down the driving 'nut' from the X axis left side handwheel to fit my coupling so i could use the left hand X axis handwheel to move the Y axis. this way i can remove the handwheel when i am not using it as my space is very cramped. (that probably doesn't make a lot of sense unless you have a similar mill). i did not take any build photo's or video.. just kinda did it.

what you see is the second iteration. the first build the stepper used a slip coupling a made from aluminum and was directly in line with the shaft, like on the X, but i couldn't slow it down enough to cut steel. so i built the belt drive to reduce the speed, and increase the load torque. in truth i like the belt drive a little better.
WIN_20190723_21_25_07_Pro.jpg
 
So it too much longer than i anticipated but i cut a box out of PVC molding purchased from Home Depot. i think it came out OK.. if i were to do it again there are several things i would do differently. but for now it'll work.Y box.jpg
 
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