Dear Tom and RP-friends,
Tom Mueller wrote:
"I would suggest that one or more universities active in the RP
community might
like to step up and fill the role played by Dupont in the past.
Providing free
measurement of standard test parts and periodically presenting
results could be
extremely valuable."
We, here at TNO, likes to step up and try to continue the work Dupont did.
As you know or not know: we are the Dutch independant research organization
(full name: Netherlands Organization for Applied Scientific Research) and do
for a lot of customers CMM-work (satalite/space/aircraft parts etc.) beside
productdevelopment and RP&T-work. Before we say a definitive yes, someone
have to provide us with a STL-file of the part the RP-community is using as
the standard test one. Also someone have to tell us:
* how many times people expect us to do this
* who will deliver the parts to us (RP-machine manufactures or
others; we prefer not only SLA but all the technologies including
milling!!!!!!!!!!!! )
* what has to be measured.
* how you all like to be reported
When we have to do this every week 1 day then it will be to much but when it
is once every month, the same geometry, for 1 day then it will go ok (in
between is maybe also possible).We can automate this and then it can be
handled!
Let us know and let someone step up to tell us what we asked above !
Bye from a rainy/snowy/cold Holland
Jan Willem
Ir. Jan Willem Gunnink
TNO Industrie
Division of Production development
Department of Industrial Prototyping
P.O. Box 5073
2600 GB Delft
Holland
Tel: +31-15-2608747
Fax: +31-15-2608725
E-mail: j.gunnink@ind.tno.nl
> I think that the CNC machined parts were supplied by Light Machines and
> were
> machined on one of their tabletop CNC systems. The parts were measured by
> Dupont on their CMM system. It would be very interesting to see how the
> accuracy
> of a part machined on a high end CNC machine would compare.
>
> The old timers like Elaine and I will remember that Dupont would measure
> the
> test part developed by the SLA user group free of charge and would
> periodically
> report the results(provided the owner of the part allowed the results to
> be
> shared). By providing an unbiased measurement service and a standard
> measurement technique, Ed Garguilo and Dupont provided an extremely
> valuable
> service to the RP community and were the only unbiased source of accuracy
> information available. Further, the attention focused on the topic by
> Paul
> Jacobs while he was at 3D Systems did a lot to improve accuracy throughout
> the
> industry.
>
> Unfortunately, both Ed and Paul are in different positions, and the
> division of
> Dupont that owned the CMM machine has since been sold. It is no longer
> possible
> to have SLA user group parts measured accurately at no charge, nor is
> there
> anyone collecting information on accuracy in the way that Ed did in the
> past.
> To my recollection, the only accuracy data published in the last few years
> was a
> paper I presented last year at the RPA conference.
>
> I think it is increasingly important that accuracy studies continue. As
> RP
> moves into more demanding applications, in particular rapid tooling, the
> viability of the application becomes increasingly dependent on the
> accuracy of
> RP systems used. I believe it is important that unbiased information be
> available to the RP community.
>
> I would suggest that one or more universities active in the RP community
> might
> like to step up and fill the role played by Dupont in the past. Providing
> free
> measurement of standard test parts and periodically presenting results
> could be
> extremely valuable.
>
> Tom Mueller
> TJ Mueller & Company
> 2314 Magnolia Court East
> Buffalo Grove, IL 60089
> (847) 821-8809
> (847) 821-1634 fax
>
> Elaine Hunt wrote:
>
> > >Several different RP systems have been used to make the standard user
> > >part. Has anyone made this part with a CNC machine and measured the
> > >results against the STL file to determine the accuracy of the NC
> machine
> > >on on absolute basis and relative to several RP processes?
> >
> > I believe that Ed Garguilo's report included an CNC'ed user part out of
> > Aluminum. I'll hunt around for the paper and see if I can find it. The
> > initial study was WAY back in the early 90s and using the ole 5180
> stuff.
> > This study has not been repeated using any of the newer resins. As far
> as
> > relative to several RP processes... the standard user part was 9.5x9.5x
> 1.5
> > so it would not fit in some machines..also I think that maybe 2 machines
> > were commercial when the first report was done. Heavens do I feel old.
> >
> > Elaine
> > *******************************************************************
> > Opinions, suggestions, and other controversial matter VOID where
> prohibited.
> > ******************************************************************
> > Elaine T. Hunt, Director
> > Clemson University Laboratory to Advance Industrial Prototyping
> > 206 Fluor Daniel Bldg. Clemson, SC 29643-0925
> > 864-656-0321 (voice) 864-656-4435 (fax)
> > elaine.hunt@ces.clemson.edu
> > http://rafiki.vr.clemson.edu/credo/persall/persall.html
> >
> > For more information about the rp-ml, see http://ltk.hut.fi/rp-ml/
>
>
> For more information about the rp-ml, see http://ltk.hut.fi/rp-ml/
For more information about the rp-ml, see http://ltk.hut.fi/rp-ml/
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