Bob Darrah wrote:

PL wrote (snip)

Looking up the rate of thermal expansion on cast iron gives:
.059 inches x 10 -4 per degree F
or .0000059 inches per degree by moving the decimal to the left by
four places.

If we start with room temp 72 F and go up to 500 F that is 430 degree F

change

in temp. So the rotor should be only about .0025 wider if my numbers are

correct.

Thats per inch,  since the rotor is "about" 3 inches thick, you have to
multiply that number by three.

The way I remember this is that a 10 inch piece of iron will expand about
.006 of an inch per 100 degrees F.

Rough estamate, rotor thickness is ~1/3 of 10 inches, temp rise is 4 (+)
times .006 gives ~.008.

Bob Darrah

Good work Bob. Right .008" wider. Thanks.

Paul Lamar


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