Went out of town for Thanksgiving and when I got back, I jumped into my MPCNC only to find the upper lock on the Dewalt tool mount cracked in two. My son prints up my parts and he said it seemed to crack in a strange place, given design of the part.
I’m running a standard MPCNC (no burly, yet), 24" x 24", 3/4" EMT Conduit. I’ve only added the dust mount to the gantry area, using the original upper lock. The lower mount and lock pieces get replaced with the dust mount. I only have about 2 hours of cut time on the machine. Here’s the original post of my machine in the build area ( for more info and pics ). I did tighten the upper mount to the point of contact of the upper mount and the upper lock, but no further.
Any advice? More infill? Tightened too tight?
I’d hate to see a failure like this on a long cut…
That vac hose is a torque multiplier pulling on the upper bracket. I highly suggest you mount the flexible part of the hose to your shoe and then to the XYZ piece to relieve any tension. I have not come up with a good vac shoe design yet.
As for the break that is a very odd place, but you do have it on upside down.
I got the new upper bracket from my son and as I took apart the old one, I noticed that the ‘up’ was in the up position, which made me wonder if I had it wrong or if you made a mistake from my picture…
Up goes up on the upper bracket, right? I searched around for a good pic and couldn’t find exactly what I needed, so I checked out Thingiverse for your part and it shows it (not attached) with ‘up’ readable, from left to right.
You might have had the front piece correct but the back piece was not. It sticks up above the toolmount part. you can kind of see it in the thingiverse second picture. I will try to get one not black on black when I have a printer freed up.
