Howto make 6 inches into 12

Kurt in NJ

Well-known member
With Hershey coming I figured I would share a method I thought up to measure brake drums with the cheap harbor freight 6" caliper---

Using any known size in the range you want to use this method you come up with a number to set the calipers at---then zero it

The older one in the picture the correction factor for 12" is 2.704---if you want to measure an 11 inch drum you use 1.704

I mark the correction number on the caliper, I have a newer "pittsburg" 9.95$ with coupon that the correction number is 2.717 for 12", I havn't checked at the store to see if it is close enough to use on others of that series

the brake drum in the picture is quite thin at .168 over 11 inches, the drum surface is only .020 thick
 

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Knew a guy who asked same of his doctor.

His Doctor replied, lots of products on market; but, none he knew of actually worked.
 
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I saw a cutaway display at the Gilmore a couple days ago.
When you see the stock drum, a very worn drum, and the new cast iron drum, it's easy to see why the cast drums offer so much better braking.
 
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