Taz 6: two corners of build plate too low

I’ve got two corners of my build plate (upper right and lower left) that are consistently lower than the other three. It’s making it impossible to print out a bunch of copies of an item while maintaining a smooth first layer. I have tried: making sure the X axis is level, making sure the bolts on the probing pads are nice and tight, leveling the rods in the Y axis and making sure they are parallel, making sure the z-axis has no binding in it, making sure the nozzle and probing pads are clean (and watching it closely as it levels), and resetting the printer to factory settings… I’m running out of ideas! It does not seem like this should happen, as all the auto-leveling does is figure out the z height of each probe pad and subtract the thickness of the washers.
Here are some test prints, done in the center and each corner (printed right next to the probing pads). I get the same results with S3D and Cura. Thanks.

I have a similar problem. In my case it’s that the build plate isn’t flat. As far as I can tell, the “auto-level” measures the corners correctly, based on the output from the probe printed on the console. The problem is that my plate has a saddle-shape (+X+Y and -X-Y are high, +X-Y and -X+Y are low) and as far as I can tell the firmware used by the TAZ6 just calculates an average X and Y-slope. This essentially means in my case it ends up with close to a zero slope (because the two edges are sloped in different directions) that will be mostly correct at the edge midpoints, but not near the corners.

It appears more recent versions of Marlin have the ability to do a “mesh level” that interpolates between the corner points (or even splits the build plate into a finer grid), see https://github.com/MarlinFirmware/Marlin/wiki/Mesh-Bed-Leveling. I don’t know what the prospects of running that firmware on the TAZ6 are.

I have the exact same problem The Ninjaflex corner pieces that your glass bed sits on are warn. For lack of a better word they get squished.
You need to replace them or shim the low corners.


The flexible supports aren’t really the issue for me, they all push the bed up against the flat washers, which is all they need to do, and shimming does not help. I think the problem is that the aluminum base of the bed is no stronger than the glass, so if you try to shim it you’re changing the shape of the aluminum, not the glass. At least that’s how it seemed for me.

I’m now using a Marlin 1.1.1 FW. With mesh bed leveling, it takes the four corners and interpolates between them. It’s still not 100% descriptive of the actual shape, but it’s a lot better than the “tilted plane” model in the stock TAZ firmware.