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Are there additional sources of information about RM?

Ed -

First of all, kudos on your site. It is interesting, informative and professionally done. I have been and will continue to browse the available information. Per your note that the first step in solving a problem is to let you know about it, let me describe what I’m looking for.

Based on the premise that free form manufacturing processes offer substantial potential reductions in production lead-time, concomitant cost reductions, etc., the processes appear attractive for the production of replacement parts of many different types.

We’re working on a study for the Department of Defense to try to identify processes that typically build up a part directly into net or near-net shape for DOD applications. The general approach would be to build a number of test parts using different methods.

At first we’d like to characterize the processes in a simple fashion including items such as: material and dimensional constraints, tolerances, maturity and claimed benefits.

I would like to get details related to proven mechanical properties, required secondary processing, specification references if applicable, etc. As part of studying maturity it would be nice to obtain vendor information for the processes that are in commercial use. For candidates where significant process development appears in order, ties to sponsoring and or executing research organizations will be sought.

Are there additional sources of information that might be of help in generating and characterizing the candidate process list?

Thanks,
BH

Dear BH:

Thanks for your letter and your kind words.

The correct approach to the problem is indeed to select specific parts for study and comparison. There are many additive processes, of course, but most are immature and have variable tolerances which are a function of the geometry involved. There isn't yet a whole lot of public data available for most of them outside of the incomplete data that the system vendors will provide - and being immature they are moving targets anyway. There have been very few direct comparison studies, and most of those are now too old to be of much interest.

The most thorough compilation of processes and their properties that I know about is on our web site. Please see the tooling and rapid manufacturing section, especially the comparison tables beginning here:

http://home.att.net/~castleisland/tl_c.htm

You should also look at the introductory section for RP beginning here, especially the quick overview table:

http://home.att.net/~castleisland/rp_int.htm

You may also find parts of the FAQ's helpful, especially the manufacturing applications portions:

http://home.att.net/~castleisland/faq/faq_c0.htm

There has been a lot of government involvement in the field in the past and there continues to be. Indeed, some of the processes have arisen out of government lab work and government-supported R&D, especially those involving laser powder forming. There are extensive listings for government programs starting here:

http://home.att.net/~castleisland/gv_lks.htm

Probably one program of particular interest is the Mobile Parts Hospital. These guys are solving the same, or a similar problem, for a different reason. Take a look at the link for "RP hits the road for the military" on this page:

http://home.att.net/~castleisland/pw_arc7.htm

Thanks again. I hope this is of some help and I send best regards.

Ed

Ed Grenda
Castle Island Co.
The Worldwide Guide to Rapid Prototyping