I thought they were something like tool steel. Hardered steel? IDK, I’m not a metal expert.
I think you have to keep them oiled or they rust, so I don’t think they are SS.
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I think description says it’s carbon steel
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How do I square x-gantry? Frame is squared and I just measured that it is x-gantry that is off. Changing belts tension helps but does not completely close the gap and also make belts tension disproportional
Removing belts entirelly make x-gantry loose and easily squared. I have a feeling it is belts related but don’t understand what I need to do. It’s not like I skipped a tooth somewhere right?
Already checked the assembled frame is square and plumb (so not racked/skewed) using a framing square, or something similar that’s large and square?
https://azab2c.com/make?s=squar&v=2_0&r=1.4
During assembly, discovered my build wasn’t as square as I thought, had to redo some work. Despite efforts to square, I still had different sized gaps on the left and right side. Ended doing some test Crown prints and using Klipper skew correction to get Square prints (in XY), even if I couldn’t get the frame physically ‘True square’ in XY.
Edit: Just noticed V1E MP3DP v4 doc has section on squaring.
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Yeah, luckily I used a square while I was building the frame and checking now - frame is squared. As I said all good without belts. I just tighten belt on one side and it is squared, but I am questioning now if I have too much tension. Is this a thing?
Already seen Matt's MP3DP Repeat Build - #153 by MattMed , some of the posts there helped me figure out belt tension. Correct tension ended up being way looser than I expected. Doing some motion tests helped with verifying if/what tuning was needed https://azab2c.com/make?s=motion&v=5_5&t=34_09_10&r=1.05
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I just learned on my most recent build that the best thing to do is to get the X axis as square as possible BEFORE putting any belts in. With no belts attached, leave the X rail mounting bolts (4 bolts) loose so you can wiggle each side back and forth somewhat independently. Then I used a pair of calipers to put both XY trucks in the same position dimensionally from the back extrusion rail. Once I had them both in the same spot (square) I then put stop blocks on either side of each XY truck to keep them from moving. Now I can belt the XY system knowing the X-axis is set square and cannot move. This results in a pretty square axis when I am done and then can make small adjustments with the tensioning.
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Just powered board for the first time, moved motors around and figured I have a problem - what you all do in order to prevent a catastrophic bed drop?
Personally haven’t figured out how to prevent for all situations (e.g. power loss, reset or filament sensor trigger). Have tried to reduce number of conditions that result in freefall via Klipper Macro that moves to safe height after print completes, or before idle timeout powers down the steppers.
Saw MP3DP Repeat V2 (aka V4) z steppers - #6 by kwledbetter, but am not sure if/what config/mechanical solutions others have tried? Personally considered counter weights even…
Maybe a soft close drawer mechanism at the bottom to catch the bed or a small trapeze net?
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In the event of power failure… not much you can do.
Maybe brakes on the Z axis, if the ENA pin on the motor driver is logic high, the brake is released, otherwise engaged? This might be fast enough to catch the Z axis in a power fail. Will almost certainly be enough on a motor power down, but I don’t know that I’d want to coint on it for a print resume, given that a mechanical motion is necessary to engage.
My v4 has a home routine using sensorless homing to the bottom of the travel, and I add that to the end of my print routines… but that can’t work on the SKR boards. You could add optical stops and use v3 firmware, maybe? At least I don’t get the bed dropping on power down.
Counterweights are tricky, because while you can account for an unloaded bed, once the print starts, the weight is harder to balance. I suppose you could probably get close enough for friction to manage. But it’s kind of messy at best, and subject to all kinds of potential problems.
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Can someone tell me the order of Z motors? Having an issue with Z_STEPPER_AUTO_ALIGN (fails before 1st measurement, no other debug info provided)
when looking from the front opening, Z is the front left, Z1 is the center rear, Z2 is the front right. (at least on my machine as defined in the klipper printer.cfg file) You can test these in klipper with
STEPPER_BUZZ=stepper_z
STEPPER_BUZZ=stepper_z1
STEPPER_BUZZ=stepper_z2
from the terminal.
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Apparently my problem was me not resetting EEPROM after changing XY positions for z leveling. Anyways, here is my very first print without cooling fan (amazon did not deliver it today and I could not wait)
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The arches anchor holes, and top of the window look perfect. It looks great! Congrats!
While in the process of input shaping I noticed there is rippling not associated with acceleration or frame vibration. It is much more prominent then Y axis is moving and less noticeable on X. As the speed of printing increase - this tippling starting to smooth out but spacing between ripples is the same regardless of the speed. I am assuming this has something to do with the motor /belt / gears on the Y axis?
X axis also moves much more noisier than Y axis but surface is much smoother
I think your belts might be a bit too tight. I think that stuff is the concentricity of the idlers and pulley’s but it only shows when the belts are super tight. The belts across the back should not make a sound when plucked.
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It’s pretty loose now, definitely not making a sound when plucked. I was able to tune up the belt a bit but that stuff did not fully go away.
Printing at 200mm/s and 3000 acceleration
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