Auto level failure

After about 20 good prints, I had an auto level failure. It went to the four corners, and seem to press down too hard. Then when it went to print, it went down too far and dug a trench into the bed.

I know it looks for a current flow from the print head to the washer to calibrate where the bed is located and if there is sufficient insulation on the print head, this will cause the failure. My question is

1.) What is the best way to prevent this… clean the print head is the obvious answer, and I did that… but any suggestions on the best way to clean it.

2.) Does a failure damage the bed or the print head?

–Jim

Heat up the not end to 10-15 degrees lower than your usual extrusion temperature and wipe off the nozzle with a dry cloth/paper towel. The bed and hot end should be fine, but watch the next couple of prints to make sure.


The worst case divot (photo attached) is bad enough where it causes the second not to stick to the first layer… or the first layer to be cut off. The divot appears that the peak to peak height is about twice that of the 3M 468MP material you use.

Know of how to smooth it over, or change material?

Since auto leveling can fail, is there a way of detecting different conditions… or stopping and ask for confirmation. If the position has changed significantly from previous settings… should it just halt?

Considering that my first heated bed covering lasted a week, and that you charge $25/sheet. It seems like it would be better to buy a roll.

http://www.zoro.com/i/G5527636/?gclid=CN2k75z_8MMCFRSPfgodMgcAgg

You’d get thirty shots for less than twice the price.

That source for PEI sheet doesn’t work, as you need more than 6 inches in width.

After thinking about the failure. One suggestion to anyone is to be sure to observe the auto-leveling. If the head pushes down and deflects the bed… then then head needs to be cleaned. If it does this ABORT and make sure the head is clean
Does that sound like good advice?

Yes, good advice.

PEI isn’t meant to be consumable like PET. It is very difficult to remove, due to the adhesive. It is meant to last much longer. If the bump is up, it can be sanded down. If it is a divot, it can be filled with a glue or similar. I don’t have details on what type of glue would be best, but we’ll have an answer to that.

Thanks,

-Jeff

The problems started when I switched to PLA. I had printed flawless with HIPS and ABS, but when I went to PLA that is when things went bad. Yes… I manually extruded the new material. Then the auto level failure dug up the hot bed coating. It was difficult for me to get PLA to manually extrude in a thin filament. It loved to form loops. I did one successful small print. Then on a larger print the 3mm PLA stopped feeding. I cleaned the “hobbed Bolt”. Did another print… again, the 3mm PLA filament stopped feeding after about an hour.

I must be doing something wrong. Am using the profiles (PLA_medium_mini.ini)

I moved back to HIPS… and it is working like a champ.

–Jim