[robgross1930]

Originally Posted by Synchro909

That has been playing on my mind too. That's why I thought I would ask about it here. That said, the original mechanical brakes of the day all (as far as I know) all used steel drums.
When did they change to bonded linings and when did they (car makers) stop using steel drums? Did those two things happen at the same time and if so, was it because they encountered the same problem as my fellow club member?
Put another way, did car makers use woven lings with cast drums?

Bonded lining means bonded to the shoe using a bonding process that uses a special adhesive. The solid looking linings, as compared to woven, are “molded” linings. Some molded linings are bonded and some are riveted. I have also seen woven linings that were bonded and of course riveted which is what we like for Model A’s.

The softer the lining material, the greater the coefficient of friction. Ford made a “soft” molded lining, I think about 1932 or so, maybe later, that had a greater coefficient of friction than the typical “hard” molded lining. The woven lining, being soft, has a higher coefficient of friction.

There are only a few things that one has to really consider: the type of brake system and the pressure it’s capable of applying and the coefficient of friction of the type of lining used. A brake system that has a weaker applied pressure, i.e., mechanical brakes, requires a soft lining that creates more friction, such as woven, to have the best brakes with that type of system. A brake system that has a strong applied pressure, i.e., hydraulic brakes, needs a harder lining with a lower coefficient of friction, such as a hard molded lining. If a lining with too high of a coefficient of friction, such as woven, is used on hydraulic brakes, the brakes can grab or lock up. On the other hand, a hard or harder molded lining used on mechanical brakes will not supply enough friction relative to the pressure applied on the shoes, and the brakes will be poor as compared to woven linings.