Bed Leveling is not repeatable



  • I have set the bed level and done a test print. I then go back and reverify the level. The level is not consistent. Every time I adjust the level it is off when I check it. I am not putting any weight on the bed when doing the bed leveling. I am using the same piece of paper held in the same manner.

    Is it normal to have the center of the bed bowed. Again I have adjusted the bed level on each corner and then when I check the center the bed is lower than the edges.

    Have others seen this issue? BTW I have installed a BL Touch to try to deal with this but it is currently not doing any better.



  • all the advice given is good advise.

    but there is 2 more thing to look at.
    the X gantry has to be assembled and this is where you might have to check.
    the 2 screws that secure it on either end will allow a small amount of movement if not secured well. (i had a similar issue) and might be moving slightly when the printer is printing.

    the second is the runner wheels that the the X gantry rolls up and down on.
    make sure that these are not over tightened against the tracks as this would cause too much drag and might be affecting you alignment / levelling issue.

    my bed on my ender 3 v2 was also slightly bowed up in the centre of the bed (0.2mm) and i had to print in the middle for a while. however after a while (a week or so) my bed has settled (i think it was the heat cycles) and is now almost completely flat. it seems that the alloy bed, being press stamped, will never be perfect but should settle down. (unless its way off)

    i level manually and don't have the BL touch.
    i have not had to level my bed now for about 4 weeks and only check it if i have printing issues witch is zero at the moment.



  • @NUCInnovations It sounds like you have a good mechanical aptitude, so I probably can't tell you much that you haven't already worked out for yourself.

    My manual leveling process starts by raising the print head, and then inspecting the nozzle with a mirror (I actually use a ladies compact mirror, as this is small and gives a magnified image). I make sure that the nozzle's flat orifice is completely free of plastic.

    I then heat the bed to 60'C and leave it for another 5 minutes. I've given up heating the hot-end/nozzle as this will ooze plastic and make it difficult to check/adjust. The nozzle could be heated to a temperature below the material melting point, but I've found this unnecessary.

    I use a very old (1960s) '3 thou' feeler-gauge (I used to tune cars too!) which I think equates to approximately 0.075mm. Obviously I can't claim that my bed is leveled to 75um, because its down to judgement & feel as to how much drag I can feel when making this crude adjustment. Also, adjustment of the 4 spring loaded adjusters is very sensitive; it would probably be easier if they had a finer thread, and if there was only 3 (not 4) equidistant adjusters.

    I no longer bother to re-check the bed-to-nozzle gap before use. If its printing OK, I just use it. When things start to go wrong, I will check & readjust if necessary.



  • @NUCInnovations I used the cr touch because i had similar with a glass plate. Found the clamp needed to be offset of each other and not center. Also when adjusting, heat the bed as it changes when it's temp changes.

    This helped me, but now my prints are taking 3x longer. Wondering if the offset setting is causing the main board to do to much math.



  • I am leveling the bed by repeatedly setting each corner until I have the same value on each corner. I am using a 0.2mm feeler gauge and obtaining the same feeling on each corner. I have done a lot of valve adjustments in my life so this is not usual for me. Note clean the feeler gauge if you use this method. I used a set dedicated to adjusting the printer. I have printed a part and then come back the next day to recheck the bed level. It is not the same. The bed has tilted. I relevel and print my next parts.
    I installed a BLTouch to deal with this but I found the fact the level changed disconcerting. Most people will not care but I am doing very thin parts and the thickness of the part is important. After a pain setting up the BLTouch the parts are coming out looking good. I am doing the bed leveling with the BLTouch att the start of every print session.



  • I'm not sure exactly how you are manually leveling the bed, so just to clarify; you adjust each corner in turn with a piece of paper. You should then go around again, rechecking and re-adjusting as necessary. Each corner adjuster will affect some or all of the other corners. So you should always end up doing at least 3 final checks after your last adjustment.

    There may be some distortion of the bed in the centre, but it may not matter. If you think this is causing a problem; try printing a small object in the centre of the bed, and then print it again near to one of the bed corners. Is one print clearly better than the other?

    BLTouch seems to be a bit of a nightmare, so I haven't even taken mine out of its box (...it was a gift).


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