GM has built cars with large 3D printers. Engines and all.
They can get a new curve or bend or fit the next day.

24 hour turn around and not cutting blocks of clay over and over.

Martin

On 10/23/2015 5:00 PM, jim wrote:
wrote:
On Friday, October 23, 2015 at 11:57:21 AM UTC-4, Ed Huntress wrote:


Oh, and you're right, making patterns for casting is one of the
original uses for 3D printing. Also, some people use some type of wax
or plastic made for the purpose, and make investment-casting patterns.
I've never looked into it, though.

--
Ed Huntress

I did a little looking around. The material used for investment
casting is PLA. Made from Soy Beans. The regular material gives
toxic fumes when being melted out.

Back around 1980- there was a 3d printing technique
using laminated layers of paper that was big in
pattern making but CNC machining soon pushed it aside.

Today most of the metal casting using 3d printing is
in the jewelry making business. Not much for
foundry casting.

Z-corp makes a 3d printer that prints objects made of
sand.
Its used for making sand molds and cores for
making prototype or one-off castings.
http://www.zcorp.com/zcorp/casting-material.html