My printing is progressing slow and steady. Right now only the tall parts remain. I just printed the tool mount, and I noticed a sliight skew in the print… aye caramba, this project has a long learning curve!
What can cause this? The bed is levelled thouroughly and no warping or obvious shifting has happened. Can it be y-belt that’s not properly tightened? Or is the y-axis not perpendicular to the bed? I thought it would be all right when it’s levelled correctly?
I also wonder if this is too much distortion to make it work with the pipes. I will know for sure in time…
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Edit: I got useful help from a ender-3 board. They figured out what was wrong - the vertical axises was not 90 degrees on the horisontal plane! That explains the whole parallellogram-shape. It’s too obvious when you realize it. Now I’m trying to adjust, but the whole thing is a little wobbly and unstable. I’m positive I’ll figure it out in the end. I bought the printer used, and have had many issues with it. It’s annoying, but a good learning figuring out the kinks!!
I bet you can make that skewed tool holder work. What’s more important is how perpendicular your tool spindle is to the workplane and I believe there is enough “loosen the screw, square it up and retighten” to make that happen in Ryan’s design.
Thanks! That was reassuring. I’m more worried about the xy burley though! Guess I have to do a little troubleshooting and test prints before I go for the biggest print jobs.
Hmm - I see that my travel speed settings have been way higher than what I’ve believed it to be. 120 mms. I guess it has fallen back to a default value when I’ve messed around in Cura. Can a high travel speed cause a slight skew during the print? (it’s a very annoying to troubleshoot this, because this height and serious size takes considerable time to test…)
Doubt your travel speed will do that skewing, excessive speed would/should create issues regardless of how tall a part is?
Also - it looks like you’re using the bottom of the part as the reference, does that skew show up in the hole patterns? Maybe this is a bed leveling issue. Maybe try installing long screws (with nuts) into the 4 mounting locations and see how square the hole pattern is?
Your printer is not square. Chances are good your Z smooth rods are not right. I really suggest not printing any MPCNC parts until you fix the printer as that is a very large error.
Test your printer buy printing a very large cube and measuring the edge diagonals in every direction. Normal “calibration” prints are only testing steps per mm, not the actual machine.
Thanks Ryan. You are (not suprisingly) correct! I adjusted the vertical axises their sideways direction, had to lay in some aluminium foil under the right side of the axis bottoms to get them square. What I DIDN’T measure and fix, stupidly enough, is the y-direction of the vertical axis, since it didn’t seemed skewed that way. I have printed a big test tower, and it seems fine in all directions, but I made it with the sideways direction in mind. Thank you for learningful input - this is sure a journey full of new knowledge…
Ahhh - dear sweet mother of… reminder to self! Don’t buy cheap 3d-printers used… I’ve jumped down the rabbit hole, trying to get the axises perfectly square. They are not square at all, no matter how much I try to loosen and tightend each of the two screws - from the underside. SO WHAT DO I DO? I get down and dirty and do my best with small aluminium shims, from foil and drink cans. The digital caliper sure comes handy now. Should the shim be 0.1 mm or 0.07 or 0.05?? It makes a huge difference when trying to get something square! One down, over the rainbow, my printer will be kind to me - and I will finally get to assemble the MPCNC.
Isn’t it crazy. Think of all the reviews and videos with people talking about how amazing the prints are form there super cheap printer…No one ever, ever, ever verifies the accuracy of the axes. Shows you just how good all those review channels are.
