PLA not sticking to bed.

[Rockface]

So, my new ender 3 printed the first 4 things pretty well. There was a bit of stringing but otherwise they weren’t too bad.

I then changed the filament to black PLA and suddenly nothing would stick to the bed.

Can someone tell me what I should be checking.

I’m running the nozzle at 190 - 200 and the bed is at 50C
I have cleaned the nozzle 3 or 4 times with a cold pull, I have slightly lowered the z offset, I have cleaned the bed, I calibrated the PID, I calibrated the extruder. None of these things have had any effect. Nothing sticks. I’m running out of ideas.

 

[Rockface]

Couple of simple things to try:

1. Wash the bed with dish soap
2. Put a thin layer of glue down on the bed. Use pritt stick or something like that

Thanks. I’ll give that a go. Presumably pritt stick should be cleaned off and reapplied after every print? If so, will soap and water wash it off ?

 

[Rockface]

The problem has been solved. I cleaned the bed with acetone and now the test print has worked. And the extruder seems to be behaving itself.