MPCNC: will you make it work? (pretty please!)

Hi Tom,

I enjoyed your MPCNC build! I think I’m not the only one who would love to see a follow-up (I’m planning to build one). People over at V1 seem to think the culprit could be your spindle - but I’m sure you have your own diagnosis.

Pretty please??

Thank you for your great work :slight_smile:

Cheers
Till

I too loved the series, but I took from it that the design might be difficult to tame as far as vibrations go. I’m starting to look at the LowRider-2. I have even done a SketchUp drawing (3D Warehouse, search for “Lowrider 2”) to get a feel of it…

Hi Guys,

I have built a MPCNC and used it for over 6 months. It is absolutely fine for wood (I haven’t tried aluminum or plastic). The recommendations from the V1 site would have had Tom do smaller DOC (3mm or less), about 15mm/sec, and a single flute upcut endmill. My spindle is the recommended DeWalt.

My first project cut through American red oak with no splinters or vibrations, using both a 1/8 and 1/16 inch endmill.

Tom, check out this. His YouTube video shows how the double belt reduces the amount of belt flexing, I think he is on to something.

There is a fair amount of feedback on that last video now.

Did you tighten _____?
Spindle mounts need to be spread further apart.
Z axis reaches too low.
Z axis tube flexes. (I think this would be due to the last 2 or 3.
When chatter happens, slow down the feed rate till it clears up and repeat on this next pass. Failure to slow down on chatter spots will amplify it more and more for each pass.
Do not use the full width of the bit.
Re-enforce this part.
Try a different tool path generator.

That is a loose summary of most of it.

Due to the licensing thing our school has decided to do one from “scratch” using 2020 extrusion. Guess I will post progress here if its ok. It will be open source so if anyone has any ideas how to share designs I/we are all ears. We design in Inventor as the school teaches that so - sorry everything that comes from us is in IPT. I might even resurrect my youtube channel for this if there is a request for that. Currently it operates on a request only as there are less than 100 subscribers (way less) and I/we use it to pass info on to other teams on request like the Volumetric E thing and how to design involute helical gears in inventor

what a shame, I was going to build it. But damn…

Really, when I saw the whole zip tie thing for attaching belts, I was thinking that was nuts and that the belts (I do not know why I said zip ties before) should go through the holes where the zip ties were or that the whole thing was stupid. A clamp down method for holding a belt is what I am used to. Zip ties seems kind of nuts.

10mm zip ties stretch less than he belts. It works just fine.

Since Stefan posted, I reread what I posted and noticed that I said zip ties when I meant belts in one of the spots. Ugh. I keep messing up my wording here and there.