I’ve had an Ender 3 v2 for a few years now and have had mostly no issues. I’ve upgraded the hot end to a microswiss direct drive and a dual z setup (twin z steppers on a shared cable).
Recently started having issues with the 4.2.2 board and replaced it with a BTT mini SKR 3 v3.
Since I’ve put the new board in, I am having troubles getting the bed to level and stay level.
The height profile of the bed is now showing a dip in the centre (which was not there before). When I run a print it seems to be overcompensating for the dip. If I level the bed with the corner screws and don’t use the bed mesh then it prints fairly good, but after a few prints the bed goes out of level again.
I can’t seem to make any adjustments that help the issue. Yesterday tightened up all the screws (silicon spacers instead of springs). Releveled the bed and had a small dip in the middle and an overall height difference of 0.170 across the bed (normal prior to this was 0.310). Sent a print with bed mesh and mostly came out good.
Went to fire up a new print today and the bed height is showing 0.830 overall difference.
I’m not sure if it is a BL touch issue (the BL touch is a v3.1 and is original with a single 5 wire connector plugged into mini SKR) dual z issue (disconnected 1 in an attempt to level and didn’t see much difference, the BTT has two connectors for dual z but run off one stepper driver as I understand it, I am using the y cable for only one stepper motor, while the other motor has its own cable).
I use klipper with a RPi zero 2 w.
I just can’t seem to figure out that has been causing the issue since the board swap.
Anyone have some ideas as where to point me?
I had weird stuff like that start to happen with my BL Touch. Turns out the bracket I’d printed had started to crack in a hard to see spot, so every bed mesh I took was a little different. Am ordering a metal bracket to replace it.
Tbh, I threw the bl touch in the garbage and just eyeball my levelling. It’s never failed me on any print. Takes more time and patience but I know it’s done right.
I’ll try running sans BL Touch, it’s just weird that it was working before the board change without issue. I’ve cranked down on the silicon spacers to make sure it’s difficult for them to loosen up over time, will see how that goes.
Thanks for your comment.
You might also try running a few leveling probes in a row to check the repeatability of the measurements. It’s possible that something is messing with the ability to make good measurements (unstable power feed, heat warp, probe binding, etc).
I’ll give that a go. Thanks for the idea.
Would seem odd, but if it seems like your leveling wheels are backing off, maybe the threads are worn on them? It would suck to replace them only to find out that wasn’t the issue though, but if you have a spare set / originals if you’ve upgraded, maybe see if those are more stable?
I have aluminum wheels in place if the original, they seem to be staying tight, but maybe not.
I did notice that the plastic heater wire retainer is deforming in the middle, so maybe that is contributing, I will put a larger washer on it when I reassemble the unit.
Thanks for the comment.
BL touch works great but you need to get the Z offset. Then you can just G29 before the print or whenever and it works great. I hate manual levelling and these days there isn’t much reason for it. I’ve just upgraded to a Bambu P1S and levelling is even more straightforward since there is no Z-offset since it uses the hotend itself to probe.
Not sure how hacky you want to get, but I found that my E3V2Neo got significantly more accurate once I set up independent z control.
Unfortunately, the Mini SKR only has 4 stepper drivers, so I used my old 4.2.2 board in conjunction with the Mini SKR and klipper to enable z_tilt_adjust.
I had a ton of trouble (bed leveling) with the regular dual-z upgrade until then. It’s pretty easy to run another set of 24v wires to the old Creality board and I found a printable case to hold everything. Just make sure you use one board for both Z’s rather than splitting them across two boards to avoid latency.
I’m happy to post my klipper config if you want to try it.
That sounds like an interesting plan, my E stepper driver was what acted up on my 4.2.2, it seems to be working now, but I’d like to see your config in case I need to go in that direction.
I had an issue like this and it was my bltouch lost it’s accuracy. Try rubbing a repeatability check. PROBE_ACCURACY.
I did a probe accuracy test yesterday, 0.002. So I think it’s good.
I have the entire printer torn right back to square one. Will double check everything as I reassemble.
Did a couple prints yesterday with no BL touch, bed level the four corners, seemed good a bit of first layer micro adjustments.
Went to perform another print (same as the previous print) and the bed was out of whack again. The bed level test said that the right side was out half a turn on the knobs.
I’m starting to think it has to do with the dual z motors and not staying timed or level with each other.
Will see how it works once I get it all back together.
Thanks.
In my Ender 3 Pro I found tightening the screws too much made the bed bow, so I loosened them until they were just firm but not forcing up the corners. I also replaced the default springs with stiffer ones so once set they stayed set. I also built a custom Marlin firmware and I changed the bed mesh algorithm to probe more points and use a more sophisticated algorithm to compensate for levelling. This was with a Bigtree 1.2 board which barely had enough memory for the firmware but I made it work. After that I really didn’t have any issues. Biggest pain was dialing in the Z-offset on the BL touch.
It could be that I am cranking down on the wheels too much. Thought that maybe they were loosening off so tried to tighten them. I’ll keep that in mind when I reassemble the unit.
Thanks.
Update:
I took everyone’s advice and tried all the suggestions. In the end I completely disassembled the printer and made sure everything was square or perpendicular where it needed to be. I think maybe the dual z screws were binding, although when I took everything apart I noticed that I did not use the Y cable for both z steppers, I ran the original short cable to one motor and
the Y to another, not sure if that had any effect or not, but now the Y cable is running both z steppers.
It does seem to be better, but I still have the dip in the bed, which is still a bit of an issue for the BL Touch, but not nearly as bad as before. I may have slightly bowed it when trying to crank down the levelling wheels.
I think that the z screws were binding just enough that it couldn’t keep up with the micro adjustments, I guess time will tell.
Thanks for everyone’s input and advice, hopefully it’ll run for a couple more years. If not then a replacement Bamboo might be in order.
Now I just need my resin printers to stop failing prints, but I think that’s more me than the printers. lol
Thanks everyone.