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RP for large parts?

Ed,
Thanks for providing your occasional email newsletter. I find it very interesting and informative. I have a question for you.

In addition to designing products for a Fortune 500 company, I am also an inventor. I am currently working on a new type of marine product and have built several hand-made prototypes.

I have been a user of RP for injection molded parts for years but was surprised to find that most RP vendors have ignored the large part segment. I realize their are a lot more smaller injection mold parts and the relative tooling and lead times are higher but it seems there is a need here also.

Do you know of anyone who has done work developing an RP process to prototype very large rotomolded or blow molded parts and/or their tooling?

I have been toying with some ideas but I am sure I am not alone.

Any help would be appreciated.
DW

Hi DW:

Thanks for your kind compliments and your letter.

There are very few choices for large-part capable RP systems. The most likely possibility for you at the moment is a stereolithography system that was developed by Materialise, called the "Mammoth." I don't recall the max dimension specs, but this thing is capable of popping out an entire auto dashboard at one time with pretty good precision. Materialise is a SW company, of course, but also provides SB capabilities in numerous countries.

The only other possibilities are the LOM systems made by Kinergy (Singapore), but the technology might not offer the kind of finishes or functionality that you need. I don't know if they still make it, but at one time 3D was producing an SLA that had 1 meter capability, but had limitations on depth of about 4 inches - might not be big enough for you, but some SB's might have the capability.

Other choices are things like LOM variants from Univ of Utah and Gilmore Engineers (Australia). Very big stuff, but mainly plastic foam capabilities. Formus in Calif was at one time making things the size of cars, but very limited technology for what you need, and I as far as I know they've ceased to function. Contour crafting from Univ of Calif (Khoshnevis) is applicable to large ceramic objects, but still in fairly early stages and aimed more at the building trades.

Off the top of my head, that's the sum of your choices, I think. Materialise is your best shot and they're easy enough to find listed on our site.

Thanks again and I send best regards.
Ed

Ed Grenda
Castle Island Co.

Ed,

Thanks for the quick response. I will look into your suggestions.

I appreciate the help.
DW