When is a Model A drum under size?

Can someone tell me what thickness a model A drum can be machined too befor its under size.
Thanks
Brendan

 

You mean Oversize ?

 

You say potatoe I say patio or something like that, when are they ready for the bin.

 

Cast iron --or stamped steel? Cast iron can go .050" safely. The stamped steel are not supposed to be machined. Consider using new cast iron drums that look like the original drums.

 

The minimum "safe" wall thickness for steel drums is .120". Anything less than that I throw on the scrap pile.

 

Thanks
.120 now I have some thing to look for.
Brendan

 

Bredan the trouble with model A sheet metal brake drums is that they get hot and distort under heavy braking and expand out so they become more over sized than when cold so you loose your brake shoe adjustment when hot.
If you want mechanical brake may I suggest you find yourself a 1935 front axle complete and install it onto the model A radius rods, that way you get a lower front, open cast iron brake drums and slightly bigger diameter drums, just need to make a steering arm to go onto the spindle.
All the lever will do right up.