Re: CO2 Lasers

On Sun, 08 Aug 1999 21:50:30, Bob Bachman <bobach@...> wrote:

>A cnc laser machine was making 3d models out of successive layers of paper
>glued together.
>...
>The model was built-up
>in .003" to .004" layers - each sheet slightly different in contour to create
>the third dimension.

Some of you are probly driving a car who's engine castings were built
using this technique. You are if you own a Saturn. Much of "lost foam"
casting masters for their engines are made by cutting successive layers
of EPS, and then glueing them together using a platen to paint the hot
glue on, followed by a "press" affair to place and hold the layers
together. The layers aren't of course paper-thin, but the cuts are also
made at a conforming angle, so you don't end up with "stairsteps"
either.

This also allows them to cut and stack together complex core/void
volumes, instead of having to construct actual cores themselves. All
that's necessary is that these voids are reasonably open somewhere for
the dry sand fill to enter, that is sifted in everywhere following
slurry coating. So, much of the complex 3-D character of engine blocks &
heads can be made without cores to create these voids.

Now think of THAT as a real live plausible application of your CNC'd
laser cutting system. Cutting and constructing "lost-foam" casting
masters you can then have turned into aluminum at a lost-foam foundry!
Whohee, heady stuff, eh?

Gar