William wrote:

we are considering bringing ours but it is all cut up and partially

polished... not representative

of the product received.. removed 24 oz so far.
...Chrissi

Chrissi,
Can you post a picture of your efforts and where the most material came
from?
Bill Schertz

One thing Bill, Chrissi has a 3rd gen so there will be differences.

Paul Lamar

Here is front and back. Except for trimming the edges and hogging off material, the rest was

done

with an air die grinder (thumb is recovering nicely).
One small slip inside the port edge may require welding and regrinding for a good seal on

gasket.

Nice work Chrissi. Can I send you mine and have you do the same thing?
I'll have to modify the pattern and make them look like that.

Paul Lamar

Paul, wish I could do more of this but need to find better techniques first. It's nasty work,
about 2 full days worth so far.
Would rather work on a soft pattern and get them in that condition then cleanup and polish.
Wondering if pour foam could be used in lost-foam technique? At the very least, use pour foam in
tooling to make soft foam cores, foundry can thenjust pack sand around foam and burn it out with
the metal. The melted "glaze" as the foam melts back against the cooler sand makes for really
smooth surfaces... at least with styrofoam patterns.
...Chrissi

As I understand the process... you need a metal female mold for the foam.
Styrofoam beads are placed in the mold and heated with steam to expand.
sounds expensive. One offs would also be labor intensive.
The lost foam model is placed in the sand and cast. Pour foam to my knowledge is
an adhesive so the mold surface would need a parting agent.

I think we can change the sand cast pattern a bit and save a little more
weight.

Paul Lamar
 
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