My printrbot simple still doesn’t print right. I’ve been trying all kinds of experiments.
Basic problem all prints slanted in X. So…
I’ve pulled the X motor and applied rubber tubing from a slingshot. It’s NOT slippery like original tubing. It has not slipped on the motor shaft, I checked.
I made a guitar tuning peg X tension adjuster. I can adjust the tension probably up to the Spectra breaking point (80 pounds).
I ran a long series of tests of tension, current, speed, acceleration and angled prints.
Here’s the weird parts: (see the pictures)
if I print with the test object rotated 45 or -45 degrees by itself I get a good print.
if I print at 0, 15, 30 degrees it’s slanted.
if I print a 0’and 45 together at same time, both are slanted.
I ran a series of tests at 0 degrees adjusting current. Had X current potentiometer at noon through 3 in 15 degree adjustments. All tests slanted up toward positive Y but one at 1:30 clock angle slanted the opposite way half as much. I tried the 1:30 current setting again today and it slanted the same old way!
I noticed this same issue when setting up a Jr. on summer and thought it was a mechanic problem. I was using Cura (13.04?) and the original firmware for the Jr. Didn’t manage to find a consistent solution. I will keep an eye on this, good luck!
Your description of having issues at 45° angles only when a 0° copy also was printed got me thinking: Does it help if you limit acceleration to some insanely low value like 200mm/s² to rule out positive X slipping when it reaches a 90° corner?
How fast are you running? When you print at 45 degrees, the X and Y components of motion are 70% of the specified feed speed. When running at 0 or 90 degrees, the X and Y components are 100% of the specified feed speed. It might also be that you need a more relaxed set of acceleration parameters.
It could also be that whatever slop in the system is adding up when you’re hitting one of the four corners (from the energy released from changing directions) that is causing a temporary mechanical binding. Try to wiggle the printer pieces in X, Y and X+Y and see if you see any play that could allow motion components to be pinched.
On the ToM, for example, there was inadequate clearance between the X belt and the slot made to allow the belt to pass through. Usually, there was sufficient gap, but when the belt was vibrating at higher speeds, it was possible for the belt tooth to catch the edge of the slot. (Solution: enlarge the size of the slot.)
I am assuming that your print is not hitting the x extreme? The only time I have had the slanting is when I hit the mechanical limits. This could explain why it happens at 30 deg, but not 45.
+Camerin hahn
I read about a similar problem caused by a limit swich triggering (probably caused by some bad connection or wiring) but it only occured when the printer jerked in a certain position causing the same kind of slanting you are seeing. He couldnt locate the actual fault but there was a setting in the firmware to use the limit switches only when homing and that solved the issue for him. (I dont know how safe that soultion is in the long run but it could help to troubleshoot to see if the problem is with the limit switches triggering?)
Since the jerk decreases with angle it sound like a plausible problem.
@Alan_McNeil I have had leaning issues if print objects above 90 mm, with certain orientations. I am using the simple as well. I don’t think I can reliably make things above 85mm in the x dimension.
Using Slic3r (0.9 something) and repetier host. (latest). @Hannes_Lilliefeldt good idea. I can force the steps in X to an integer and see if it is still slanted. I think it’s 119.25 right now.
Anyone know what the Kysan part number is for the CURRENT X axis motor on @Printr_bot simple? It would be nicer to replace than swap X and Y (more disassembly).
