Hello,
Did you ever resolve your New Departure Model A issue? I have a mid teens Pierce with a ND model A and have overhauled many times to try and get reliable stopping power. I tried one of the brake sleeves and it improved mine but was still not great. Eventually I bought a replacement brake set, part A8 and found that my old brake disk assembly was much smaller in diameter from wear, the new one would not fit in the hub with the sleeve in place. I pulled out the sleeve and the new brake assembly really improved braking but as someone here on a CABE has said these hubs are not so much brakes and speed attenuators. There are some who say theirs stop on a dime and can lock up the tire. Not mine, it still has issues engaging when you backpeddle, sometimes 4 or 5 times before it starts to drag when you first start riding the bike. After a few minutes riding it becomes more reliable but still only engages about 80% of the time and may engage immediately or back peddle half a turn before you feel drag. It keeps you focused and planning ahead.
If you've found the solution to your braking issues I'd (and I'm sure others here) would love to hear about it. These brakes have such a small thin bit of metal on metal contact compared to later brakes it's no wonder they dont' stop as quick, I should probably build a rider wheel with a model D, Morrow or Bendix before its too late...
View attachment 1139828