has anyone see this problem before (bltouch/bed)



  • I'm having the strangest issues with my BLtouch / bed leveling.
    no matter what i do, i end up with this (see pic)
    has anyone see that before, any idea what could be the problem?
    I'm running a bl touch classic, i have tried with and without the resistor
    for the record, if i go to each of the 4 corners and send the nozzle to z0 it's almost perfect.
    so this image is crazy off for some unknown reason



  • I couldn't seem to upload it here
    here is a link instead
    https--------photos.app.goo.gl/5oZF2r4edex83SUPA

    the forum kept telling me my post was spam
    remove the ------ add ://



  • Odd that it's so consistent in the tilt.

    alt text

    What firmware version are you using?



  • @ianborg Just three ideas:

    1. You seem to home Z in the left front edge? If this is true, your probe offset might be a little bit too high.

    2. Did you level the bed with the BLtouch or with a feeler gauge / a sheet of paper? It might be worth to double-check the result with just the other method.

    3. Can you trust your mechanics? Maybe it helps to tell us what kind of printer you run.



  • @Phaedrux I'm using the latest, (duet wifi) It was also the same with the last firmware.
    I updated hoping that may have been the problem, but it doesn't appear so



  • @infiniteloop thanks for the reply
    i'm running an FT5-R1 (non-stock)
    I'm switched out almost all of the melamine with milled aluminum
    I am confident in the mechanics, i was running an MKS 1.4 before and things were fine. the heater cartridge connection on the board stopped working (no power), but everything else on the board was fine and worked. i decided to upgrade to a duet wifi instead of replacing with another mks.

    The FT5 homes to the back right corner 0,0
    so back right is 0,0
    front right is 0,300
    front left is 300,300
    back left is 300,0

    i'm using a jig i printed on another printer to make sure the 4 corners are adjusted the same
    I also use the paper method and when i move the nozzle to the 4 corners, i get near perfect results

    I also used a printed jig to ensure the bltouch is 8mm from the bed per the bltouch specs

    my next step is to replace the bltouch and hope it has something to do with that?
    but before i did, i thought i would check with others here to see if it might have been something i was doing wrong related to the duet setup.



  • Hi, I had a similar problem and maybe it's not your case but it could be an attempt to do.

    Detach the bltouch
    Unscrew the hexagonal screw above the piston
    Exit the plunger and clean it
    Blow gently inside (do not insert anything)
    Put everything back on and adjust the screw so that it is 0.3 (more correct: - 0.3) under the mounting surface (compared to the 0.3 more screwed top)



  • @luc thanks i'll give that a try and report back



  • so i think i have it sorted. turns out while my bed was pretty level, the mirror tile & pei sheet on top of it were not. but it wasn't something i could easily see, i had to take my printer out of it's spot and when i looked around with a flashlight, i could see a small gap, i pressed on the corner and sure enough it had give, the corner bracket i made, had it bunched up a bit and being in the back corner of a shelf, i couldn't see it without taking the printer out..
    i took the dremmel to the bracket and the glass now fits without binding up.
    re-ran the mesh bed leveling and am getting much better results.

    I guess what threw me off was how extreme it looked on the graph. i'm like there is no way things can be that far out of wack. but once i fixed the bracket, it is much closer to what it should be.

    appreciate all the suggestions.



  • here is a photo to show you can see the bracket on the corner, i ground it away and the tile sits flush now.
    photos.app.goo.gl/RRype9WyK23GTihd7



  • @ianborg

    I’m running an FT5-R1 (non-stock)

    Fine machine. How many Z-steppers does it have - didn’t find that in the specs. Is there any possibility of the 4 treaded rods coming out of sync, for either electrical or mechanical reasons?

    The FT5 homes to the back right corner 0,0

    Then, I think your mesh shows a look from the back, but anyway, that does’n matter.

    my next step is to replace the bltouch and hope it has something to do with that?

    Whatever BLtouch or other probe you take, you must make sure that it is trustworthy, so you should repeatedly probe a single point with G30 S-1 and look if the reported values are identical or at least very narrow.



  • @infiniteloop said in has anyone see this problem before (bltouch/bed):

    didn’t find that in the specs. Is there any possibility of the 4 treaded rods coming out of sync, for either electrical or mechanical reasons?

    The FT5 homes to the back right corner 0,0

    Then, I think your mesh shows a look from the back, but anyway, that does’n matter.

    my next step is to replace the bltouch and hope it has something to do with that?

    Whatever BLtouch or other probe you take, you must make sure that it is trustworthy, so you should repeatedly probe a single point with G30 S-1 and look if the reported values are identical or at least very narrow.

    originally it had 2 z motors wired in series? off of 1 z driver, but the R2 version used a single Z motor with bigger belt so allot of us that had R1 machines also converted over to a single Z.
    to your other question, if i had the original melamine parts, then i would say yes possible, but that is why many people started getting the milled aluminum parts to replace. if you were curious check out 713maker.com that's the guy who makes all the aluminum conversion parts.


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