Hello fellow humans,
Which controller are all the cool kids using these days for high powered motors? Say I want to build a 3-axis CNC mill. Smoothie ? Ramps ? I’m kinda out of touch with the controller board world.
For high-current applications, it really doesn’t matter much which board you’re using since you’ll (hopefully) be using external drivers anyways. Technically, all you need is a bare Arduino with any firmware, which you can hook up your driver’s step, direction and enable lines to.
Can you recommend an external driver?
Geckodrive and Leadshine are two big names that are know for good quality driver. They are far on the expensive side, though.
Definitely stay away from Toshiba-based drivers (TB6560 and such). You need to touch them with velvet gloves, and even then they blow up in your face sometimes.
Is 2.5A per coil enough to drive a CNC mill ?
no, if your going to cut you’ll want something around 4. Check out probotix. They make great stuff and have the drivers, motors and everything.
Thanks, does the probotix work with open-source software, or is it locked to it’s proprietary app ?
2.5A isn’t exactly a scientific measure of torque - NEMA23 motors and drivers generally also require greater voltages to work nicely, but it depends on the exact motor you pick as they come in tons of configurations.
What kind of torque you need will also depend on the pitch of your leadscrew, the speeds you want to reach, which materials you want to cut and whether or not you gearing the motors.
And if your converting a mill, building from scratch etc. Ive done a few scratch builds and conversions so if you need help I can give some direction.
Yes, I need to take a step back.
The goal is to make a CNC for our hackerspace which will be able to cut wood, acrylic and aluminum. We are going to use OpenBuild’s OX as the frame and I’m now trying to figure out which motors/board we need.
For a machine that size I would recommend 400oz/in motors for at least your long axis, if not all.
Also looking at that machine, and its variants, I would want to change the belt routing. on all the axes the belt is only contacting about 20% of the pulley. You really want at least a 50% wrap of the belt if your going to put cut forces on it.
I’m using these at the moment, i combination with a ramps board,since I wasn’t satisfied with the standard drivers.
http://www.ebay.com/itm/CNC-Single-1-One-Axis-TB6600-5A-Two-Phase-Hybrid-Stepper-Motor-Driver-Controller-/151021546953?pt=LH_DefaultDomain_0&hash=item232995edc9
These work quite nicely for me.
@Rien_Stouten Wow that’s cheap.
no kidding. what amperage are you running
@Shachar_Weis fwiw I’ve scratch built a CNC from essentially scraps and cheap hardware. Sparkfun easy drivers and small steppers. I’ve successfully cut wood, hdpe,metal etc. I wouldn’t necessarily recommend going my route. But just wanted to say that it is possible to achieve a lot without having to go crazy on the specs. It’s very easy to get drawn in to spending a lot of money. And that’s before you even think about a decent spindle and some quality cutters.
@Joe_Spanier 2,5Amps, at 24VDC
Ok that seems reasonable. Im curious how those would react to a full 5 amps
Me too. I have a feeling they won’t like it.
Poorly, would be my guess. I would not try that with those drivers “out of the box”. They use no thermal paste between driver and heatsink, and without it, they would surely fail at 5 amps.