PLA first layer lifting

The attached photograph shows the problem I get, which is particularly bad on large flat areas. If I can get the first layer to stick, the rest of the print goes pretty well. Once the problem starts, each pass makes it worse and the second layer can just tear the first to bits.

I'm using a Lulzbot Taz 4 with a Budaschnozzle. I've tried brand new PLA from two good sources and the outcome is the same. I'm extruding at 180 degrees onto a 50 degree bed, although I've tried 200 degree with a hot bed and with a cold bed.

I'm printing at 20mm/s, but I've tried it faster in case that helped somehow.

I don't run the fan on the first layer, but I have tried it with the fan running.

I've made sure the bed is level / tram and made it closer and further away to check for differences.

I've tried plain glass, PET tape (the Lulzbot default surface), Garolite / Tufnol and 3M painters tape (pictured). I've tried gluesticks, PLA wood glue, and lemon juice (God help me).

What am I missing?

Did your print become more transparent when you tried lemon juice?

Have you tried lowering the nozzle slightly so the first layer smooshes a bit more into the bed?

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Try hair spray. I have my bed @70. Nozzle at 225. Used to have hexagon hot end and never had an issue with pla. Only with abs lifting.

Now I have the Prometheus hotend and I am having some trouble. I have to make sure my bed is sticky or the pla will lift. Buy I think it has to do with how I have the hotend setup. With Prometheus I feel that I have to turn down the heat on the nozzle to 200 but I have to test further

Like 3dkarma said as well try lowering ur nozzle closer to the bed. .1mm gap

Edited 1 time(s). Last edit at 11/27/2014 06:00PM by nefiwashere.

It happened the same to me when printing very big first layers (7" by 4.5") and it affected maybe a 25% or 30% of the area. I put the fan at 100% and reduced the speed at minimun (100 in my manual control) that gave chance to the last injected line to get hard before the hot end comes back and inject the next hot line. This change made a very good improvement, though very few overbuilt is still forming; the good thing is that the dragging and tear is not longer happening. Please give your insight.

Wow, that is pretty horrendous lifting!
If it were me with a new machine, I would verify the mechanical straightness and flatness of the machine:
1) Verify that the print bed is very flat as manufactured? Lets say less than 0.1 mm variation in flatness over the full width. As in testing it by taking a metal straight edge (manufactured) to it and seeing no light underneath the full length from end to end and repeated going both directions in many locations.
2) Check straightness of X an Y rails.
3) Verify that the stage or nozzle does not wobble or is loose allowing movement from a straight line path by manually giving it a little pressure from several different directions with your hand with the printer turned off.
Also you could check that the nozzle is set for the first layer at less than your nominal layer height like 1/2 height, 3/4 height. Reference Z-axis zeroing procedure if necessary.
Since a little hotter settings for extruder and bed did not work, we can look elsewhere... Does the room have an oscillating fan or random airflow over the printer that may disrupt its temperatures?
If 20 mm/s did not work, maybe try 10 for the first layer. It should not be required usually to go that slow, but it may help if there is some problem with certain prints, or some unidentified issue. Frequently the first layer is slowed to like 1/2 nominal speed to help adhesion.
You could alternatively try printing with a raft which will make a level surface for your part.

Those are my best suggestions, I hope they help...

I have a TAZ 4 and have never had a problem like that. My only real guess would be the filament based on what you have tried already. I know you said good sources but that would still be my guess, if possible get a sample from Ultimachine or Lulzbot. Those are my 2 suppliers.

Thank you for all your suggestions!

I've finally tracked down the problem with help from this post.

It came down the ratio between my layer height and my extrusion width. An extreme scenario would be a 1mm layer height and a 0.1mm extrusion width, so effectively each strand of filament stands tall and narrow above the bed. The head must then navigate these "canyons" of plastic to lay down adjacent strands, and inevitably the head can pull them up and cause the problem I was seeing.

I was using a 0.25mm layer height with a 0.35mm extrusion width, but a ratio in excess of 2:1 (flat and wide extrusions) works better. I switched to 0.5mm extrusion width and everything was fine. If I want to trade speed for accuracy I can use 0.1mm layer height with 0.35mm extrusion width.

A notable mention goes to lowering my bed temp from 60 to 50, which made a small improvement originally. Apparently "blistering" is a typical symptom of a hot bed.

This all comes down to first layer basics - you must compress the first layer into the bed whatever settings you have.

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Waitaki 3D Printer