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Ignoramus29895 Ignoramus29895 is offline
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Default Shopmade grinder with winch.

.... Or so was that lot described in the Rock Island military auction
where they sold off contents of one of their buildings that they want
to remodel.

I bid on it for no good reason other than liking the Thern 1/2 HP winch.

It turned out to be bigger than I expected.

But what it turns out to be is an aluminum degasser. Which can be
described as a big pole with base to bolt to floor (about 8-10 ft), a
arm, and a motor to drive a special shaft through which argon is piped
into molten aluminum. The point of a degasser is to remove hydrogen
that is dissolved in molten aluminum. Aluminum is so prone ot
oxidation that it dissociates water molecules, turning into aluminum
oxide.

2Al + 3H20 = Al2O3 + 6H

The hydrogen gas remains dissolved in aluminum until it cools down and
begins to solidify. and then forms bubbles, which ruins the
casting. Here comes "degassing", which releases hydrogen by stirring
molten aluminum and adding inert gas through the degasser and its shaft.

I can post pictures if anyone is interested.

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