3D Systems DuraForm TPU Elastomer, Installation Manual - Original Instructions

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3D SYSTEMS, INC. 75-D059 REV_A 15
Increasing the laser power significantly will help a part to stop curling, but this will also cause growth on the part.
If severe curling occurs , you may want to terminate the print and begin a new one . Consider the following changes to prevent the
problem in future prints:
• Make sure the system has gone through a full Warm-up stage .
• Check the feed bed Set Points and the Print Heater Set Point .
• Excess feed material may contribute to curling during printing as some of the feed material may not be hot enough,
especially with short layer times .
• Make sure Cylinder Heater Enable is set to 1 and the Cylinder Heater Set Point is set correctly .
NOTE: Adjust parameters in small increments to avoid introducing problems caused by too much heat. If
temperatures are raised too greatly and too quickly, the material can start caking.
CURLING, POST-PRINT
Description : The final part is not flat and is showing curling similar to
that experienced with injection-molded parts .
Theory of Cause : When the part is buried during the Print stage,
excessive cooling rates and thermal gradients produce unbalanced
stresses in it . Excessive cooling rates usually occur on parts printed
first in a print job (the parts at the lowest Z levels). You may also have
removed the print from the print chamber prematurely .
Visual Signs : The final part is not flat. You cannot observe this until the
part is broken out .
Consequences : Curled parts (especially those with large surface cross-
sections) are not flat, but the Z dimensions are correct.
Corrective Actions : You can attempt to repair curled parts, and you
can change your prints to prevent future runs from curling .
Preventing Curl in Prints
You may want to take one or more of the following actions to prevent
parts from curling:
• Increase Print Bed Set point : Increase the Print Bed PID Setpoint
by 1 or 2 ° C. Increasing the Print Bed PID Setpoint too greatly may
cause a more difficult breakout and reduce the amount of material
that can be recycled.
• Change Part entation : Rotate the part 15
°
around the Y and Z-axis;
this reduces cooling stresses.
• Print in Layers : Print parts at the third or fourth layer of parts in
the print cake . For information on setting up a print in layers, see
“Setting Up a Print” on page 4.