Bed Leveling

Noob question.

I know this is a common issue (and therefore a probably common thread) - but I need some pro tips regarding bed leveling.

I’ve tried searching this forum but keep getting the “search terms are too common” error for things like “bed leveling” or threads about automating/leveling assist mods.

I’m having a hell of a time leveling my bed (Taz 5). I’ve made a couple passes at it but feel that, in my excitement/inexperience that I’ve completely made a mess of it.

I feel like I’m chasing a moving target (that or my heated bed is warped). I’m finding the center of the bed is much higher than the corners …and every time I do a circuit to each corner and set the height, the center again becomes too high (when all corners are more or less the same using the paper test).

I hope that makes sense.

The question is: Is there a way to start over? Like setting all the screws to a snug position and working from there?
I’ve tried setting the Z in the center - then tried to match the home corner to that…but that doesn’t seem to work.

For the record - I’m doing this with the nozzle/bed ready to print HIPS (I read something about doing it heated allows for expansion).

The kicker is - I have bought a dial indicator so that I can level precisely, the only issue is - I need a level bed to print it. :-/

Thanks in advance (and sorry for asking such a basic question).

along those same lines, which may help the OP later too… has someone developed a bed calibration print? that touches four corners etc? is that on the original SD card that i got with my printer? :slight_smile:

Dunginhawk - yes.

There is a bed calibration print. It’s on the SD card named something like bed_calibration in the calibration folder (at least on the card that comes with the TAZ 5)

The bed is flat but your X axis support rods deform slightly due to the weight of the print head.

Level the four corners and try to split the height difference of corner to center height. :slight_smile:

The screws have about 8 full turns of height/spring play in them. I try to keep them approximately four turns from the bottom. If you get too high you run the risk of stripping the threading in the aluminum plate holes.

Thanks kmanly.

I hadn’t considered the sag…I’ll keep that in mind in the future (I have read about the weight of the print head being a problem but didn’t realize it would be so noticeable).

I realized this was going to be tricky but didn’t realize it would be quite this frustrating…back to it. :slight_smile:

Bed leveling can be frustrating… Dial gauges can help quantify the height of each corner, which eliminates the guessing.

Get some dial guages. Print the bracket from here. Below is how I like to use the dial gauges…

Leveling bed:

  • Attach dial gauges to the X-Axis
  • Zero the dial gauges above the bed:
  • Manually move Y to front of bed and home Z. Do not home XY, the dial gauge will be in the way.
  • Adjust corners as necessary:
  • Move Y to back of bed, adjust corners as necessary:

    Repeat above two or three times… And you’re done! I do this once a month or whenever the print starts to act funny… and on nozzle changes.

    I use 18.00 for my target height (with dial gauges zero-ed above bed), it may vary from machine to machine.

To find the right nozzle height:

  • Heat up hotend to extruding temps 190-240…
  • Slide a business card between the nozzle and bed
  • Should be slight resistance from the nozzle. Adjust z-endstop as necessary.
  • Raise the dial gauge above the bed.
  • Zero.
  • Then home Z. Do not home XY if you have the dial gauges attached.
  • That’s the number you want to write somewhere for the next time you need to level the bed.

Test print a 20x20x3mm calibration cube. Wait until 50C to remove the cube… it should pop off the bed pretty easily. If you’re sitting next to the print as the bed cools… you’ll hear a crackling at about 70 down to 55C. If it’s stuck to the bed and sliding the oyster knife under the print doesn’t do it, then you need to incerease the nozzle distance to the bed… quarter turn on the endstop knob.

Once the calibration cube comes off the way you like it, then go back with the dial gauge, zero above the bed, then home Z to get the distance for your nozzle to bed. Next time you level the bed, shoot for this number.

Another tip. To tweak the nozzle height, I like to use the Z-Offset G-Code setting in the slicing software. For larger prints that tend to get stuck, I may add .1 to .2 to the Z-Offset. For smaller prints or a smoother / uniform bottom, put in -.1 to -.2… this will make the print stick more to the bed.

Hope this helps!
Calibation Cube - 20x20x5.stl (1.81 KB)

I printed a bracket (a couple actually). I ended up liking the type that snaps to the print head (though it can’t quite reach the back corners).

After some time I got the bed relatively level (I think)…there was a tiny amount of slop in the bracket (it’s also a cheap dial) - but I was fairly happy with the process. I liked the quantitative feedback - subjective feedback is too imprecise for a precision machine (it’s too bad it’s not built into the stock design).

I was impressed with an example of a user measuring to half a thousandth of level…(here:

I’ll keep at it - I’ll be trying a couple other bracket designs. :slight_smile:

Awesome! I guess my preference was to leave the tool head alone once everything was level… just snap off the dial gauges. But to each their own. :slight_smile:

It gets easier, and you won’t have to do the bed leveling very often… you may get the urge to tweak the nozzle height, but do it through the z-offset in slicing software… then take that value into consideration the next time you level the bed with the dial gauge.