Extrusion problem?  

Re: Extrusion problem?

so the bad side was down? is the bad part facing the same direction everytime?

Re: Extrusion problem?

Yeah, the bad side was down. After beating my head against it some more I've convinced myself it's all about adhesion. I can print beautiful PETG all day but PLA sticks to the PEI like a wet noodle on teflon. At 30% speed and a mashed-down Z setting, I can print PLA at a hope of maybe 50% getting through the first layer without it spontaneously peeling off. Without mashing the Z it won't even begin to grip the bed, and any faster will tear it off. Even if I speed it up with a full millimeter of plastic under it, rip.

Re: Extrusion problem?

have you* washed off your bed dish soap and a water rinse then dry. that does magic for my pla when it wont stick.

Re: Extrusion problem?

have to washed off your bed dish soap and a water rinse then dry. that does magic for my pla when it wont stick.

I am going to strongly agree here. Almost every bit of advice including using glue stick or whatever for PET unnecessarily complicates things for me. For PET I just put the sheet in the fridge for a few minutes and even small parts release gently. For PLA, a print day begins with a soap wash, and then subsequent prints of that day can then get away with just an alcohol wipe. I don't have my printer in a sterile cubicle in some office dungeon, it is in my living space where I breath fart cook etc.

Re: Extrusion problem?

There's a heat problem there for sure - too hot.

I do agree with the comments on adhesion, I use 100% alchohol between every print, I have no issues with adhesion. Do not try to remove items from a hot bed, as has been said wait till it cools. If you're concerned about the surface prep it by wiping with Acetone, the only thing that I've done (but only once) is removed the top layer using a running tap and P2000 wet and dry on a block. I'm still on side one of my original sheet which I've been printing on almost daily now since January.

That said I'd recommend a full calibration again - that looks like the Z steppers are out of whack, I'm surprised it passes the bed levelling, don't ever turn the threaded rods by hand once you have calibrated. If it isn't that then I'm sure this is too much heat combined with Z height issues.

Start basic - single layer square at different places on the bed - make sure you get the 1st layer expected in all locations.

Re: Extrusion problem?

Turns out the gears on the extruder were a bit too tight and I've loosened that up a bit. Dish soap and water are pretty great too, I've seen IPA as the standard method over and over but for whatever reasons it doesn't seem to help nearly as much as dish soap, in fact I'm beginning to suspect adhesion gets worse after I clean with IPA. Can't explain it but as long as I have a solution it's OK with me.

I don't think there's anything off with any of the motors, like I said PETG prints perfectly every time, and as long as the PLA makes the initial stick it will make a beautiful square. It's just tricky to get past those first few centimeters. Cleaning less often, cleaning cold, using less IPA, using dish soap occasionally, these have all helped, but it's still not perfect. Temperature is an interesting suggestion, I'm just using Slic3rPE presets but maybe a sensor is off? I'll see what I can do to test that.

Re: Extrusion problem?

sometimes I have to preheat with the nozzle close to the print bed to get a good first layer too. OR just start a print, see how it failed, start the print again and like magic it works. always seems to be start a print. stop it because it fails, then start again. keep in mind this is only after a tall print, or after it cools down. so don't be shocked if pla does funk like this.