Fix PLA prints which start to curl or peel off bed

GORDON.LAPLANTE

Administrator
Staff member
#1
If you find your prints are peeling and curling during a print this is because parts of the model are cooling while other parts are warm causing warping.

The gMax comes with an acrylic bed which, when sanded, provides just the right amount of adhesion. it is recommended to sand the bed often. Sanding will also ensure your print has a smooth surface at the bottom.

We recommend using a 3M Coarse sanding sponge which is wet to ensure acrylic dust doesn't get into the air. This sponge can be found at standard home improvement stores such as Home Depot or Lowes. http://solutions.3m.com/wps/portal/...0000_nid=GSVNG1BLV6gsRJ5GMFSMV0glJSN7S4K1BTbl
 

Attachments

#2
I sure haven't seen any curling with Colorfabb. On the contrary, I had to chisel one print off the bed by taking a hammer to the scraper! Might try the olive oil trick someone else posted to reduce adhesion, although that runs contrary to everything I've learned in 2 years of printing with ABS on perfboard and glass!
 

GORDON.LAPLANTE

Administrator
Staff member
#3
I've learned a few things about adhesion:

When you start a print check your first layer to determine if the plastic is printing very close to the surface. You will see the plastic printing very thick lines and by the second layer you will hear the extruder rumble over the first later. This means the first layer is too close and you should manually back off the z-axis motors (by manually turning them). You should also increase the z-axis endstop screw (turn clockwise) which will increase the distance of the 1st layer so you don't have to adjust the motors in the future and when you start the next print it will be worry free.

Also our config file sets the 1st layer temp at 199 degrees C (it was 196) and the fan is off for the first two layers. The higher the temp and the longer the fan is off the better the adhesion but also the harder the print is to remove. You can lower the first layer temp in the slic3r setting to fix this or you can sand the bed. I've also found that the longer a finished print remains on the bed (like when I go to bed at 2am and wake up at 8am to check a print) the harder it is to remove (I have memories of the hammer as well). The trade off of not needing a heated bed is it may stick too well when removing but I feel this greatly outweighs the alternative. Now that ours are dialed in I literally strike the edges of the prints with a scraper and they pop right off.

Hope this helps