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Is their a good method of making aluminum disks from molten aluminum? I have a large amount of aluminum castings and I would like to make rounds that could be chucked into my late and used to turn parts. Typically the castings are reduced to molten and then poured into muffin tins for storage or use later. It is difficult to hold the tapered shape in a lathe chuck. Is there a reusable method to pour longer shapes or am I stuck with sand casting the parts?

peterh
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Rick
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A very home-spun option that should work would be to use a piece of tubing of a diameter to suit your purpose. Seamless steel tubing is available particularly on Aircraft Spruce and Specialty in many different diameters and wall thicknesses.

The temperature coefficient of steel compared to aluminum (11 to 12.5 versus 8.1)is sufficient to allow you to pour the aluminum (ideally in one continuous pour) into the tubing and allow it to cool. As it cools, it should shrink enough to slide out of the tube. The linked page also indicates that stainless steel has an even higher differential, 16 to 17.3, but I'm sure a much higher cost.

An obvious advantage to this method is flexibility in cast cylinder diameters and durability of the "mold," part of your requirements.

fred_dot_u
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  • I have never attempted pouring into a tube. I know it the hot aluminum shrinks but didn't think it would be enough. I have some short sections of tubing. I will give it a try. – Rick Nov 25 '18 at 07:09
  • You may also want to consider to preheat the steel tube to improve the differential action. A hot "hole" is smaller than a cooler one. I've had to put a sun-heated bolt ring into the freezer in order to enlarge the holes enough to put a high precision bolt through. – fred_dot_u Nov 25 '18 at 13:39