Building a BIG ONE

Hi guys,

I’ll get some pictures here asap.

I have an mpcnc that is sized to cut a full sheet of plywood. My intention for the machine is to use it just for 2D cutting. I will build a smaller one for milling next year. I purchased the hardware kit from this site, 3D printed my own parts and built a large wooden frame. I am using 18/4 wire to ensure there will be no problems with the length of the wires for this a large machine.

I realize I’m going into crazy land building such a large one. Especially using regular EMT conduit. But perhaps we can learn from my pain! :slight_smile:

My wife is cool. I have this thing in our dining room over the winter! The plan is to move it into the shop (which I am renovating at the moment) in the spring.

It is mainly assembled and operational, aside from the Z, and I can move along the X and Y axi though there is chattering.

Question #1 : I cannot manually move in either the X or Y further than 1000mm … is this a firmware limit?

Question #2 : My hardware kit came with a spring … is this to solve backlash on the Z?

#1 shouldn’t be if you are using my firmware, flash the new update just in case.
#2 I don’t understand

If using older firmware, there is a size limit.
The spring isn’t needed anymore.

Thanks guys, I’ll flash a newer firmware. Much appreciated.

Here’s a couple of photos in the meantime.

I like it. :slight_smile:

Thanks jeffeb3.

I can confirm that after doing a firmware update I am able to move past 1000mm in X and Y. Thanks to Barry and Ryan.

I made a little gcode to have the machine run it’s perimeter, and then did this several times to wear things in.

G0 F2000
G0 X0.0 Y2435.0
G0 X1215.0 Y0.0
G0 X0.0 Y-2435.0
G0 X-1215.0 Y0.0

What is that you’re using for the supports?

What is that you’re using for the supports?

The supports are something I created in Openscad.

I’ve seen others use adjustable supports and I may go that route. Mine are all the same height and I’ve noticed that some are loose compared to others. I figured that having them the same height is probably a good thing as it would consistently limit flex. I’ll let you know how these work out once I’ve used them some more.

Whats your flex like at the center with a tool hanging off it?

Setting the height as part of the print seems like a solid plan. I went the route of using bolts, but they tend to shift against the rails. I may have to do something similar…

Whats your flex like at the center with a tool hanging off it?

I haven’t installed the router on it yet Jason. I thought I’d get it working nicely with a pen first. I’ll let you know the flex soon.

Currently I am stunned into delay. With the lowrider coming out I might just re-make this mpcnc into a smaller unit (in a size it was designed to be) and build a lowrider to cut 4x8 sheets.

When will the lowrider be launched?

Just a quick update on this for those who are curious.

I tore it down and built a smaller mpcnc from it. Works great!

While the big ass version might have worked as a sheet cutter, there was more flex than I was comfortable with. Drawing with a pen was very shaky and inconsistent.

I’m glad Ryan made the lowrider for those of us who pushed the mpcnc beyond reason.


I have no idea of it.