Pouring the first loast foam flask patterns................ This is the lost foam pattern submerged in a pail of playsand. The sand is dry. I made a little air manifold with a bit of brakeline and some hose. I drilled a few holes in the brakeline and crimped the end. When you blow abit of compressed air through the sand it becomes fluidized. This allows you to simply push your pattern down into the bucket of sand. When you turn off the air pressure the sand compacts around the pattern holding it pretty firmly. The tincan placed on top of the foam sprue is to allow me to pour and keep a head of fluid pressure on the melt forcing it down into the pattern voids. This is taken just after pouring the aluminum into the can. Some of the aluminum bubbled up from under the can...not a good sign.With this can I had cut it in half and used a hose clamp to bind it closed. That allowed the liquid aluminum to leak out.
I figured the pour had issues when I looked down into the sprue and saw what looked like foamy aluminum...kind of drossy....drats.
Sure enough the pour did not turn out. I guess it was a short pour, not enough material and then some of it leaked out of the top can. As you see I only got about half of the pattern filled and the aluminum quality is very poor. Back to the drawing board.........
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