Unresolved Prints slipping on PEI surface

After seeing various youtube videos promoting the use of PEI, I bit the bullet and got a sheet of 0.03" PEI from amazon and a sheet of 3M adhesive transfer tape, for the most part its been ok but larger prints are slipping around like Bambi on ice.

I've not altered my temps, I'm printing at 210/50 and I measured the surface temp with a laser thermo gun and its within a degree of 50c, I've not changed any axis offsets either, and I have wiped down the surface of the PEI with isopropanol before prints.

Any recommendations? I've never had so many failed prints, is there a default bed temp I can alter that will fix this before I give up and tear it off and go back to glue sticks again.

Thanks in advance.

 

I would suggest lowering you Z a bit first.

I have great luck with hairspray on the glass.

(close your eyes @Geof ) Also, I've been having wonderful results using rafts. I know it used more material and it takes longer but I can start a print and go to bed and count on a new thing in the morning. Something else to try anyway, good luck.

 

The formula I've settled on for a good, reliable first layer (using PLA) is:
3M Blue painters tape, 70 degree bed, 10 line brim, 20mm/s bottom layer speed, bilinear MESH bed leveling (via latest Marlin firmware), no offset required.
Works first time, every time

 

Researched bed temperature for PLA and found 70 degrees is not uncommon. I realize many people use a lower temperature. Found that the PLA I'm using was less gummy and easier to clean up in post.
Painters tape? Because it works for me and I prefer using my scraper against the tape rather than the glass.
Brim? Because without it I was getting corner warping on thick parts that had thin ears. No more warping.
Everyone has their recipe for success, and after quite a bit of experimentation and research, I'm simply sharing mine.

 

Mark -
The settings I'm currently using are not causing warping. The higher bed temp has really helped me to achieve a good bond to the bed. For that reason I plan to experiment with the Cura "Tweak at Z" plugin to print the first few layers at the higher bed temperature, then reduce the temperature for the remainder of the print.

I also notice the outer areas of the bed seem cooler than the center area. If the bed heat was more evenly distributed, I would use a lower heat to begin. I'll get out my K thermocouple probe and see what the temperature fall off is after a 10 minute warm-up.

 

for an improvement that was supposed to be time saving, I'm seriously a hair's breadth from taking it off and going back to glue or trying hairspray.

 

I've had no problem with hairspray. Just make sure to use a piece of paper to shield the rest of the printer from overspray as much as possible. And you don't need a whole lot. Just a nice even coat will do you. I use the Aqua Net Super duper 80's rock hair band hairspray.

 

whats the clean up with using Hairspray? wipe down the bed with Windex after each print session?

 

I agree with @Geof. No need to clean each print. Depending on the print size of the print, I may not even apply any for the next. If you are a heavy printing user like Geof, the once a week sounds right. Or else every other week or so. Just don't want it to build up too much and start throwing off z offsets and such. Damp cloth probably is best. Also don't want windex or simple green on you rmetal parts.

 

one observation is that my failures seem to be exclusively with with support structures, any recommendations on how I can improve their adherence to the PEI?

 

I always try my best to orientate my prints on the bed to minimize them but I presume there are times when they are unavoidable? so far as a total newb I'm only using MatterControl.