3d prints look sloppy from Post Fire MPCNC

Hello, I am having trouble with my 3d prints

Z axis looks great, x and y show wobble.

Attached are photos of z and x/y on a calibration cube

Something is very wrong. Did a bearing fall out, extruder extremely loose??

Sorry forgot the usual biz, it’s the 23.5mm build 30"x 30" x4"

Electronics and cables we’re bought on this site. The printed parts were made from pla on an Anet a8 at .2

The printer didn’t exhibit the issue pre fire. I had to replace the feet, one of the legs, one of the roller assemblies to make it functional to this degree

I tightened the belts a bunch (just shy of over tightened)

I also tightened up the tension bolds until the gantry started to bite/slip and then backed them off a bit

There definitely is some slop in the center column, but what is seriously odd is it isn't on either axis, it jiggles at a 45degree angle,

If you have a jiggle anywhere, that apart and take a closer look. Every thing on the machine is an interference fit and should zero slop.

I got a bucket of spares (from a dissassembled mpcnc from my father in law, gonna see if I can rebuild the center column for more rigidity

I completely disassembled the gantry, one of the XY were heat damaged (the holes were stretched from where the bolts had heated up.) I swapped out parts and reassembled

The cube looks way better.


Something I noticed this morning (wasnt there last night) is a clicking noise as the y+ rolls over a certain point. I ran my hand along the X bar at the clicking point and flecks of metal were shedding off. My initial thought was the rollers were chunking the bar but they run without clicks everywhere else. I’m going to try to turn the bar so the clicking can be moved between the rollers and see if that fixes it.

Have you ever heard of rollers take ng a chunk out of the pipe?

Here is a shot from the fire damaged XY before I disassembled it further


Much better.

The zinc comes off the conduit all the time, a chunk is possible. I would guess some sort of manufacturing defect. A little twist of the conduit…all gone.

I turned the rail 60degrees, and proceeded to print the new version of the foot. A little over an hour later so later the creaking returned it’s like the bearing is scooping out the metal on the pipe. I’m going to move print in another area on the bed and see if the chunking out happens again.


Are you sure it isn’t just the zinc rubbing off as usual? It can make noise and will wear a line of no zinc but it should not go any further without months of use first. The bearings are much harder than the conduit steel and much much harder than the zinc galvanizing. It should have no effect on the tolerances, it is just cosmetic.

Here’s a video of the noise, sounds like an old wooden ship creaking




I don’t remember this noise on the father in laws build

The foot is almost done if there’s no issue with the print then I’ll live with the noise for now


Yup, the “old man” is back. Some conduit is way worse than others. Total standard sounds right there. I spend a solid year sitting next to two creaky old men printing parts in a garage 7 days a week. Slap a router on there…no sounds to worry about.

Awesome, both feet in different locations on the bed printed fine I’ll be on my way then

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