Help Request: Leveling a Taz 5, by undoing previous mistakes?

Hello,

I’m having some issues leveling my Taz 5. Hoping restoring it to factory settings will help. I’ve shared my problems below, starting off with a description of what I’m envisioning as a next step to figuring out the logic errors I’m using in my current process.

From my understanding the following aspects control alignment:

  • Stepping Motors

  • ‘Z-Stop’ (the sensor for Z, on the left)

  • Top hex nuts on the bed component

  • (?) the bed clamp tightness


    It takes me far too long to level, I’m hoping get it back to original position will help. For example, do I tighten all the hex nuts on the bed, or loosen them? I feel like my adjustments sometimes fix the problem but don’t in the long run…and I’ve watched the tutorial video, but haven’t found it as in depth as I might like or need in my situation.

Problems I’m having:

  • Calibration print works fine

  • Printing another part, it doesn’t adhere near the center, and starts to gum up the print head (of course ruining the print).

–(Before I was at this point, I had tried adjusting for the right side printing too close to the bed, while the left side was perfect.)

  • The Z-Sensor is at it’s lowest (I remember it being higher when I first got the printer a few years ago)

Thanks for your help everyone/anyone.

Here is a procedure to ensure a good starting bed level for your Taz:

  1. Check both Z leadscrews at the top where they enter the upper 608zz bearing. Both leadscrews should be all the way up and flush with the top center of the bearing as viewed from the top of the machine.
  2. with the machine off and the motors unplugged, measure the distance from the bottom of the Z leadscrew nut to the top of the lower Z leadscrew 608zz bearing. The distance should be identical on both sides. If they are not identical, manually turn one leadscrew on one side until they are identical.
  3. check the distance from the printed corner bed mounts to the aluminum bed mount plate. The distance from the bottom of each corner mount to the top of the mount plate should be the same initially, and the corner mounts should be parallel to the heated bed. It is possible for them to work loose at an angle, or to come un anchored from the bed but still attached by weight. If you have different heights at this point, reset them all to the height of the mount closest to the bed mount plate for now. This will ensure the mount is further from the nozzle, not closer to it when we start the printer back up here in a minute. THe nozzle expands thermally, it is important to level with the nozzle at full expansion for best results
  4. Turn the printer on, and heat it to normal operating temperature (bed and nozzle) Now wait a full 3 minutes.
  5. With the printer at temperature, locate a thin metal plate (about the thickness of a business card). The gauge that ships with the printer works well for this. Now move the nozzle to each corner of the heated bed, and use that gauge to carefully and without burning yourself adjust the corner of the heated bed until the nozzle is just touching the top of the gauge and the gauge is touching the top of the heated bed. Repeat this process on all four corners. Adjust the Z height adjustment target as needed to get the initial height for the first corner. Turning the cap head screws in the corner clockwise lowers the corner closer to the bed, counterclockwise raises it.

At this point all 4 corners of the bed should be at the same height relative to the nozzle. Now print the bed level test pattern gcode (on the SD card or available at download.lulzbot.com) and see if you get a good adhesion pattern that is consistant. Adjust the Z height screw up or down as needed. If after leveling you find this height drifts rapidly, consider applying a small amount of some elmers white glue or blue Loctite to the threads of the height adjuster (NOT red Loctite!) this will make it more difficult for that adjustment screw to turn accidentally.

If it continues to be a problem, take a look at the Micrometer endstop target modification.

Hope that helps!

edit:
If you find you have inconsistent results with the leveling, it is possible a portion of the frame is out of alignment, or the Z leadscrews on one side are out of alignment. There are additional fixes for that.

On # 3 the screws for the four corners should be about 4 full turns from the lowest position they will turn/tighten to.

Or turn the four screws on the top of each corner until they are snug(not tight) then turn each one of them 4 complete turns out of get them about in the middle of their adjustment range.

Note: if you try and tighten them down too much your run the risk of stripping the threading in the bed plate out. :frowning:

Great advice, I have to figure out the parts referenced by name properly, I’m afraid I’m someone who subsidized the open source community by buying from Microcenter instead of building it :slight_smile:

Hi, great help, again thanks!

I don’t see “lead screws” on the top, or am I mistaken? I see the black rods going up into the bearing you mentioned but there’s a smooth metal cap on top.

For one thing, the frame was out of alignment due to the surface not being level but I have corrected that.

Now I’m printing the calibration and it’s working…but then my prints still pop off and get jammed. Not sure why the calibration would come out ok and the same issue would happen; tho I’ve traced this issue in the past to an unlevel bed.

The black threaded rod bolt looking thingies are leadscrews. They fit into two 608zz bearings, one at the very top, and one at the bottom just before the motor coupler shaft. What can happen sometimes is the lower motor mount will not get pushed up the frame all the way during assembly, which will allow one of the leadscrews to be lower than the other. The leadscrew fits into the bearing showin in step 6 here: https://ohai.lulzbot.com/project/f528e683-a687-4e1a-80a5-73255cb5a9da/a16b1f2d-5c1f-47fe-a83d-9d68cca5d62c/ and is captured in place by the Z axis motor mount in step 8. If the motor mount isn’t up all the way, you get an allignment issue.