Strange Ripples in the Heatmap
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Here is my configuration for the bltouch
; Z-Probe
M574 Z1 S2 ; Set endstops controlled by probe
M307 H3 A-1 C-1 D-1 ; Disable heater on PWM channel for BLTouch
M558 P9 F100 H5 T6000 R0.2 A5 B1 ; Set Z probe type to bltouch and the dive height + speeds
M280 P3 S140 I1 ; Enable 5v logic for BLTouch
G31 P25 X-22.00 Y-16.00 Z0.29 ; Set Z probe trigger value, offset and trigger height
M557 X20:180 Y20:180 S15 ; Define mesh grid -
Sorry it took so long to get this next height map done, I got distracted with attempting to align my leadscrews and seeing if that helped. Based on this walkthrough: https://www.youtube.com/watch?v=T9vI6DqAcmo. Unfortunately it didn't seem to make much of a difference, but I feel better about my rods now.
So here is a second height map collected without the glass on the bed. I liked the idea of flipping the plate, but there is an adhesive layer, with it's backing sticker on it that has lots of wrinkles so I opted just to go with the bare plate. https://ibb.co/Rz9tNMk
The ripple is still there, and I'm not really sure why. I have a second bltouch, I may end up switching them out, but it seems pretty consistent with the spacing on the ridge, so I'm not sure that it will help.
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Is there something in your x axis Making it bump?
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I can't find anything making contact or interfering. Funny thing is I also tried changing the probing density and I saw the same ripples with M557 X20:180 Y20:180 S50 I forgot to take a screenshot of it. but it does one row normal, then one row crests. I'll look into it more tomorrow. But this one baffles me. I think I can still print around it, but now I am curious.
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The clue is that when bed probing, RRF moves the head in the +X and -X directions on alternate rows. So your height map shows that the nozzle height depends on whether the last move was in the +X or -X direction. Your X carriage probably tilts a little depending on which direction the belt last pulled it.
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@dc42 I think you've nailed it. While the linear rods are secure, the gantry is stable and the bearings seem to be snug, there is a bit of tilt play in the carriage. I will print a new carriage, thanks for your help, I would have been running circles around that problem for a long time.
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@Grudairian said in Strange Ripples in the Heatmap:
G31 P25 X-22.00 Y-16.00 Z0.29 ; Set Z probe trigger value, offset and trigger height
I guess this is particularly noticeable with the probe offset in Y. Can you mount it in line with the nozzle, so no Y offset?
Ian
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@droftarts My previous carriage had it mounted in line with the nozzle(~ x:0 y55). I can definitely modify the old mount to fit on this new carriage. I switched carriages because I was having jamming problems due to airflow issues on the old carriage, so I wanted to move to the official e3d cooling solution for the heatsink. Thanks for the idea, moving the blTouch mount will be a lot easier than rebuilding the whole assembly. If the nozzle (centerpoint of the carriage) stays stable enough with the switched probe position, you will have saved me a lot of time and work.
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I moved my bltouch to be in line with my nozzle on the x-axis, though it is a little farther away; x:0 y:-65. The heightmap is a lot cleaner.
I think there is still a tiny bit of deviation, but I think it's within 0.01mm. For now, I think I should be able to print with this, but when I get a chance I'll replace the carriage. I'm glad I don't have to rush to replace it immediately though.Thanks for your help everyone.
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That is amazingly flat ! I will have to examine my setup for possible tilt with travel direction change during probing.
I use the Orion piezo sensor so my sensing happens right at the nozzle but I use a CR10 3 V roller carriage and the pizo sensor requires a sort of loose nozzle. There are a number of possible sources of oddities.
I have a second CR10 printer that uses a BlTouch and I have always seen these ripples but could never track them down. This gives me a whole new dimension to check out so thanks for bringing up the issue and thanks DC42!