Unlevel centre of bed

[SQB 0]

Hi,

 

I have an ender 3 creality and I have a problem with my bed. The corners of the bed can be levelled perfectly but the centre of the bed is always higher than the corners so the filament cannot print in that area. I do not know what to do as i cannot adjust the centre directly. Any suggestions? 

[GregValiant 1,250]

It sounds like you received a warped bed.  One fix is to use shims (aluminum foil works).  If you were to cut out a square piece of foil 235 x 235 and cut a hole in the center maybe 200mm diameter and lay it on the aluminum with the build surface on top, it would raise the periphery.  If one piece doesn't work then try two.  That would certainly be cheaper than buying a new hot plate.

Another fix is to go to a glass build surface (but you still might need to shim the corners or the glass might rock).

 

You might try going with an "Initial Layer Height" of .28.  That's about the most you can go with a .4 nozzle.

 

You could remove the hot bed and try to take the "bow" out of it.

 

Finally you could replace the hot bed.  The problem with that is there is no guarantee that the replacement would be any better.

[SQB 0]

OK thank you! I will try it.