How thin is too thin .. I read .105 on thinnest part other sides are thicker Thank you Lorenzo
These drums are not real thick. The are sheet steel about an 1/8 thick. For an emergency brake it does not make a hoot. If you are going to use it as a service brake you might want to add a sleeve on the outside to add strength and thermal capacity.
Here is an older post on dimensions by Ford on the transmission drums. Wear can make the drum take on an egg shape. So if you have various thickness that may be too much wear.
J and M Machine Co Inc on Wednesday, January 01, 2014 - 03:00 pm:
Let me ask a similar question. What is the transmission drum diameter?"Quote"
The finished drum diameter as provided by Ford is 7.5" plus/minus .005" .
The question regarding machining of the drums is How much material is left?
Warpage is another problem.
Some of the early slow speeds don't have much iron on them to begin with. "core shift"
Before contemplating doing anything with a 100 year old drum I would recommend highly getting them magnafluxed.
http://www.jandm-machine.com/fordModelTtransmissionDrums.html
Thank you Ted ,And Dan Lorenzo