Re: SLS question

From: Kamara, Sheku (
Date: Tue Nov 05 2002 - 17:37:07 EET

We did a study on powder degradation using DuraForm PA on the SLS2000
machine and presented the results at last years SFF Conference in
Austin, TX.

The main objective of the study was to determine when powder is no
longer usable. Primarily, start with enough powder so that it will
provide at least 300 hours of total build time without running short.
Explore the effect on mechanical and physical properties if laser power,
glaze, and crack point are determined and adjusted before each build.

Results of our study has allowed us, at MSOE, to recycle our powder
without adding virgin for about 400 hours on our SLS2500plus by
adjusting machine parameters after certain set intervals. Powder
management is better with this system, since we don't keep track of old
powder, say over 500 hours, in separate drums for mixing with virgin.

Please contact me for further information.


At 01:28 PM 11/5/02 +0000, Brian Caulfield wrote:

Does anybody know of any study that was carried outon the degradation of
PA powder with regards to the number of times it was used on the
machine. That is the difference between virgin powder and lets say
powder that has been ran through the SLS proces 10-20 times. Does the
mechanical proerties change etc..

Sheku Kamara
Manager of Operations
Rapid Prototyping Center
Milwaukee School of Engineering
1025N Broadway Street
Milwaukee, WI 53202
Tel.: (414) 277-7189
Fax: (414) 277-7470 <>

This archive was generated by hypermail 2.1.4 : Tue Jan 21 2003 - 20:14:33 EET