Avoiding Problems when Casting Aluminum

[GreenTwin]

Base Pattern in Steel - 2014:

The first pattern for the base was made from balsawood, with the support webs 3D printed.
I made a new base pattern from steel.
Patterns are removed from resin-bound sand once the sand has set and has become hard.
A small slide hammer is used with a light impact to break the pattern away from the mold.
Balsa patterns won't last long with resin-bound sand.
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[GreenTwin]

13th Aluminum Pour - 2014:

I went back and tried the long mold with aluminum, since aluminum can be superheated quite a bit above its pour temperature, and gray iron cannot when using an oil burner.

I was able to get a complete fill of the parts with aluminum.
I cast 1/2 of the flywheel to make a pattern, but in reality, the pattern used to cast another pattern needs double shrinkage, and in this cast my cast metal pattern is too small.

The large flask and pattern layout was so cumbersome that I went back to the drawing board to look for a more manageable approach.
These parts were usable and had good surface finish.

Lots of runout onto the concrete.
This large flask size is pretty harde to manage, and produced an excessive amount of flash.
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