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3D SYSTEMS, INC
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Cool-down Stage
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The cool-down stage allows the material, parts, and SLS system to cool sufficiently enough to safely remove the print cake
from the print chamber.
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Nitrogen is required for this process and the inert level in the chamber needs to be maintained.
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The length of this stage depends on how large the print is. A larger print will take longer to cool down. The cool-down stage
lasts approximately one-to-two hours inside the SLS 380
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When this stage ends, the material and the SLS system are still hot. The final cool-down can take place in the system or the
print cake can be removed and allowed to cool-down on the MQC
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The print cake should be allowed to cool slowly to room temperature before removing the parts from the print cake. The
core of the print cake should be no warmer than 50°C.
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Removing the parts from the print cake too quickly could cause the parts to warp and/or discolor.
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Some part geometries are more susceptible to post-print warp than others.
Condensation in the Process
The DuraForm ProX PA contains a small amount of volatile material that vaporizes during processing. This material condenses
and sticks on cool surfaces in the SLS system print chamber.
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Heated nitrogen gas flow across the laser window helps reduce the condensing material from depositing on the laser win
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dow
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Heated nitrogen gas flow across the IR sensor head helps prevent condensation from forming on the IR sensor lenses.
Excessive condensation on the lenses will cause inaccurate readings of temperatures, leading to hard or melted material in
the print bed. The IR sensor should be inspected before each build and cleaned if necessary
NOTE: It is normal to see some slight condensation (or film) on the laser window after a print, but excessive
condensation on the laser window can block laser power, causing weak or porous parts.
The laser window should be cleaned before each build. See your SLS printer’s user guide for cleaning procedures.
Clean laser window
Dirty laser window
