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Any CNC help for a teacher in the GTA?


New Member
Hi everyone!

I'm a high school teacher in Milton Ontario.

We've had a CNC machine assembled but never used for years just sitting in the school. I'd love to use it with my students however the Z axis is not operating correctly.

It's based off a shapeoko 3 unit, but was made by a company called spark fun. Weird collaboration. But it does run GRBL so it should be compatible with any G-code sender.

The Z axis is "bouncy". Completely inaccurate. It can't hold it's position. Jumps up and down? Here is a video:

When I look up the shapeoko 3, it's hard to find info on this Z axis. They all seem to be driven by a screw instead of a belt and springs.

What I'm hoping for is someone with more knowledge than me to take a look at it with me and see if I'm doing something wrong, or if the machine needs repairs? Or just general help.

I wouldn't mind bringing the machine somewhere to be looked at. Is there anyone out in the GTA that is good with these things that wants to help me get it running? I'm sure my students would love to use this thing.

Thanks for reading!


New Member
Although I didn't film it, my X and Y axis seem to work fine. I was just showing those jumps you see happen on my Z axis.


Ultra Member
I think your stepper is stalling and loosing step. Take the spindle off, if it smooths out that is the cause. It means the stepper is undersized.