RE: SLS with Duraform

From: Deak, Steve (
Date: Mon May 08 2000 - 18:43:16 EEST

We're in the middle of the "bad batch" situation here. The Duraform GF
won't lay down properly, leaving sporadic "pits" in the part, and VERY poor
side walls. Cleaning the roller, lengthening time between layers and
adjusting temperatures won't help this problem. This is the 3rd time in 12
months for us to receive bad powder shipments from DTM. What's really
aggravating is we told DTM we thought the powder was bad for a week before
it was acknowledged. Gee, we've seen this twice before, we should know what
bad powder looks like.

What a killer to the technology's application penetration, especially here
in Toyland. I'll be another 6 months mending fences to my internal
customers on this, just like the last time this happened. One step forward,
three steps back. My customers only remember the problems, not the heroic

The immediate corrective action is to mix a flow agent (supplied by DTM)
with batch lots which did not get this additive. Long term, DTM needs to be
proactive in quality assurance, since they want to be (and are) the only
source for this material.

Anyone believing you have bad Duraform GF should call DTM customer support
at (+1) 800-999-5553. Have your material's lot number handy.

Steve Deak
Mgr.-Rapid Prototyping e-mail:
Hasbro, Inc. voice: (+1) 513-579-3270
615 Elsinore Place fax: (+1) 513-579-3250
Cincinnati, OH 45202 USA Making The World Smile TM

-----Original Message-----
From: Timothy J. Gornet []
Sent: Monday, May 08, 2000 8:59 AM
Subject: Re: SLS with Duraform

The only time that we see issues with Duraform not rolling out smoothly is
when we neglect to clean the roller in between builds. If the feed
temperatures are too high that can also cause the roller to "bulldoze" the
powder rather than have it "roll" in front of the roller. What problem are
you having specifically with the powder rolling?


Tim Gornet Computer Aided Engineering Consultant
SLUGNET: Vogt Bldg. Rm 101, University of Louisville, Louisville, KY 40292
PHONENET: (502)852-0714 FAXNET: (502)852-8890
Rapid Prototype Facility

>>> raf <> 05/07 2:16 PM >>>
Hello list

Did someone have problems with Duraform ?
I heard about problem as concerned the distribution of the powder with
the roller. Please, inform me about that if possible.
Thank you.


For more information about the rp-ml, see

For more information about the rp-ml, see

For more information about the rp-ml, see

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