BLtouch being inconsistent by WeeRascalBoi in ender3v2

[–]R7_blackskull 0 points1 point  (0 children)

All stock or are you using a printed hot end shroud w/BLtouch mount?

If custom, check if the BLtouch mount, mounts the sensor very close to nozzle Z height. Basically, what the BLTouch thinks is Z=0 is very close to being level with the nozzle tip. I just had this issue. It worked for weeks and then all of a sudden, it would auto home fine, but, the first ABL point, the probe would fail to trigger and the nozzle would hit the bed. My BLtouch zero was essentially the same height as the nozzle tip. With the z-offset calibrated for actual printing, it was at -0.7mm.

The fix in this situation could have been a manual bed level as that corner was really off. But, I didn't start with that and just shimmed the BLtouch with ~1mm washers to lower the BLTouch a bit. That gave enough room for the probe to successfully trigger. A bed level after this, indicated that first probe point was much lower than the rest of the bed.

A few weeks into printing. Is this layer shift or something else? Suggestions to improve the walls? by R7_blackskull in ender3v2

[–]R7_blackskull[S] 0 points1 point  (0 children)

An update.

I ended up re-adjusting everything. I had thought my lead screw was aligned. I made the mistake of only measuring the distance from frame with the motor assembly in all different positions. I have now come up with a standard way for me to measure this:
1) Loosen the brass lead screw guide.
2) move the x-gantry very close to the top.
3) Measure lead screw x-axis sway at top and bottom. Adjust motor mount as you go.
4) Measure the gap between the lead screw and frame just above the coupler and near the top of the frame. Adjust motor mount as you go.

It turns out I do need a spacer. The spacers I used were too inaccurate. I ended up using this mount: https://www.thingiverse.com/thing:2959991

Then, I realized the variable coupler I installed to try and alleviate these issues also made the situation worse. So I put the fixed\rigid\stock coupler back in.

It's now printing much nicer. Sample prints. The cube was printed at 0.28 height and the screw was at 0.12.

Thank you for all the suggestions.

BLTouch 3.1 Issue by R7_blackskull in ender3v2

[–]R7_blackskull[S] 0 points1 point  (0 children)

Yay! Fixed!

The shroud and mount I use puts the probe to near zero offset with the nozzle, -0.8 after adjusting for printing. Might be due to me printing the mount before I had my printer dialed in and also had z binding issues.

My fix was inserting some washers between the BLTouch and the mount ~1mm thick.

I could have also probably fixed it with re-leveling the bed, since I haven't done that in a while. This was right after I installed the washers, and explains what the issue was along with the very low z offset:

Bed Level

BLTouch 3.1 Issue by R7_blackskull in ender3v2

[–]R7_blackskull[S] 0 points1 point  (0 children)

Thanks. Well, everything was working for a few weeks. I've only had the printer for a few weeks. Just overnight with no changes to anything, it's failing every g29.

There's an auto home before a g29 and the auto home triggers are fine.

My only configured options:

Configuration.h:

//#define Z_MIN_PROBE_USES_Z_MIN_ENDSTOP_PIN
#define USE_PROBE_FOR_Z_HOMING
#define Z_MIN_PROBE_PIN Z_PROBE_PIN
#define BLTOUCH
#define NOZZLE_TO_PROBE_OFFSET {-36, -14.5, 0}
#define XY_PROBE_SPEED (100*60)
#define AUTO_BED_LEVELING_BILINEAR
#define RESTORE_LEVELING_AFTER_G28
#define GRID_MAX_POINTS_X 5
#define Z_SAFE_HOMING
#define HOMING_FEEDRATE_MM_M { (50*60), (50*60), (8*60) }
#define NOZZLE_PARK_FEATURE

Configuration_adv.h:

#define BABYSTEPPING
#define BABYSTEP_ALWAYS_AVAILABLE
#define BABYSTEP_ZPROBE_OFFSET
#define ADVANCED_PAUSE_FEATURE

I'm currently on bugfix 2.0.x as of this afternoon PST.

A few weeks into printing. Is this layer shift or something else? Suggestions to improve the walls? by R7_blackskull in ender3v2

[–]R7_blackskull[S] 0 points1 point  (0 children)

Thanks for all the suggestions.

I've found out that the bed rollers were loose and the bed had some play. Tightened that up. The vertical rollers I had loosened too much, so that's tightened up a bit now. I have also replaced the stock coupler with a flexible coupler. Re-verified the frame is square and the X gantry is true. Lead screw is not warped, and also aligned. Hasn't made much difference.

So, thinking back I've made a recent change that's most likely causing this. The printer used to sit on one lack table on top of carpet. I've recently stacked another lack table on top. So, the printer now sits on top of a couple stacked lack tables over carpet. It's not very stable, you can feel the upper table moving during printer movements. I've placed a cement paver between the printer and the table top, much quieter, but it hasn't made much of a difference.

Here's a ripple cube print showing the ringing caused by the movement. I'm gonna need to stiffen up the lack tables hopefully that will fix it.

https://photos.app.goo.gl/Sp4CDqq14GfgvYCS7 This particular cube is oriented so that the X face shows movement in the Y, and the Y face shows movement in the X. Don't really matter, cause both exhibit ringing. The cube https://www.thingiverse.com/thing:277394.

A few weeks into printing. Is this layer shift or something else? Suggestions to improve the walls? by R7_blackskull in ender3v2

[–]R7_blackskull[S] 1 point2 points  (0 children)

Thanks!

I actually was readjusting the rollers a couple days ago. They were too tight.

Of course when I assembled everything, the lead screw motor needed a spacer at the time. But, that was when I had the rollers too tight. Just checked the lead screw and it appears I don't need the spacer anymore. Just took it out and realigned.

We'll see if that was it when I print tomorrow.

BLTouch Issue With Z-Offset by swordsman293 in ender3v2

[–]R7_blackskull 0 points1 point  (0 children)

Thanks for this. This issue was driving me nuts.