Front brake shoes grab

[Keith]

Front Brake grabs violently when applying light to medium pressure when coming to a stop. This occurs when first starting out in the day and with a few hard quick stops it sometimes will go away for most of the ride occasionally coming back. The front brakes when applying also sound like a Mack Truck coming to a stop in that the squeal quite load.

I am running new cast iron drums with the brake shoes fitted to each drum. The linings are woven with brass wire. I have replaced all the internals, new springs, new rollers and pins, new star adjusters and tapered pins on the ends of the shoes and tracks. I also filed a nice leading taper/edge on each end of the linings.

Question: If the shoes are slightly off center will this cause the grabbing? I have access to a brake centering tool but do not know how to correct the centering if it is off. Someone mentioned bending the tracks, but they are hot riveted to the backing plates.
Keith