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Rapid Manufacturing materials that can be plated

Dear Mr. Grenda,

I am looking into RM as a means to make somewhat detailed and unique hardware for electrical fixtures for the home accessories market. The project is low volume and is intended as an offering to match existing finishes in our other product lines. Current finishes are offered in various types of chrome plating, some of which are produced at up 800 degrees Fahrenheit.

I have noticed a blend called Alumide by EOS that showed a piston sample on one web site. At first glance, I thought that it might handle the high heat requirement for the plating process. However the melt point specification is much less than what I would need, so I did not follow through to see if it could be plated.

Would you have any suggestion on what SLS machine and material to look at for plating in this application - or even if it is possible. I realize I may be ahead of myself on this use of the technology for switch and outlet covers, but the low volume RM verses conventional tooling cost does give it some consideration in my search for a solution. Maybe the research will also lead me to RM for future applications as the industry grows.

Much appreciated,

BS
Industrial Model Maker

Dear BS:

Not having detailed knowledge of your requirements, I can only suggest directions I might consider as a solution.

The material from EOS is just a nylon/Al powder blend and won't take that level of heat, as you've found. 3D Systems recently introduced something similar, incidentally, so don't bother with that. No plastic-based material used in any RP process is likely to take 800 deg F.

3D has a true aluminum material system in the works, developed at Queensland Univ in Australia, but I think any of the metal processes (St Steel, Steels etc.) available for SLS at present are going to be pretty expensive for a consumer switchplate application. They'll also likely require secondary ops and considerable finishing. Nevertheless, it's something for you to consider depending on your requirements. Here's an article on the Al material:

http://home.att.net/~edgrenda/pow/pow42.htm

A better solution might be to go with SLA or other plastic-based RP processes and use a different (more appropriate) plating process. This will give you lower costs, better finishes - and parts might even be stable if properly sealed by the plating. There are companies that specialize in plating these parts (see our commercial directory pages for listings). One interesting one to speak with is mentioned in this article:

http://home.att.net/~edgrenda/pow/pow5.htm

Another possibility is to make a tool using RP and cast a metal part from that. You might look into the Z Cast process from Z Corporation. They've signed up 20+ foundries to provide it, but I'd call them directly to see which of those might be doing something similar or have addressed similar applications. Someone in Z Corp. must be shepherding this, but I don't have a name.

Depending on your volume requirements, there could be other ways to go with indirect tooling methods, as well. Extensive info can be found starting here:

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

Best regards,

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

Dear Mr. Grenda,

I appreciate your insights and thank you very much. I have some home work to do.

No one here expects RM will be possible for this application from a cost basis, but then again it is way to begin to experiment with the plating issues to see if they can be overcome and benchmark the costs. Maybe more importantly, I think it is the opportunity to make RM familiar to my team.

My best,
BS
Industrial Model Maker