A possible solution for "corner lift"

[old man emu]

If you are suffering from "corner lift" with your prints, here's one thing that you could do to fix it.

On delivery, I saw that my heated pad was bowed towards the middle. At first I didn't think that would matter as I was going to fit a glass plate over it. However, I've been plagued with corner lift and failure to stick with my prints.

Today I was checking the calibration of my hot end. I homed the X and Y axes, and set about making the Z endstop place so that the gap between the extruder nozzle and the glass was between 0.1 mm and 0.3 mm (I used a 0.2 mm feeler gauge, but you can use a sheet of photocopy paper.) Once I had this done and therefore had set the location of Z = 0 for the machine, I sent the extruder to X = 100, Y = 100 which is in the centre of the print area. Then I homed the Z axis.

I found that the distance between the extruder and the glass was much more than what it should have been if the glass was flat. This means that when the filament came out of the extruder, it was cooling before it hit the print plate. I am going to see if I can get rid of the bowing by laying some 1/4 x 1/4 balsa stick between the Y carriage plate and the heated pad. Then I am going to take away the plastic spacers that hold the heated plate off the carriage plate before I screw the heated plate down using the screws in each corner. I put the glass on with the bulldog clips as usual.

More tomorrow after I have tried this out.

Old Man Emu

[RobH2]

I'm curious about your results because my heat bed has the same slight bow. It even bends my glass. Maybe a good solution is to get thicker glass that won't flex but I worry about losing heat. I haven't tested thicker glass to see if degrees of temp are lost per 1/16" of added thickness. Glass conducts heat really well so maybe it's a non-issue. However, fixing the bed solves all the issues. Let us know how it works out. I'm afraid balsa is too soft to do the job. You might need to use oak.

[RobH2]

I've been trying to print an object that is about 1cm wide, 4.5cm tall and about 12cm long. Every time I printed one corner would lift and shrink about 5mm. I decided to try printing on ABS slurry and it worked perfectly. All the corners stayed down. This was just my first use of the adhesion technique but so far I'm a fan. I had been using Aquanet.