Tricky adjustment for brake

I think I have my brake problem resolved.

I loosened the rear brake caliper to lightly lube certain areas.

I had to go back to the house for another adjustment after the pads
stayed on the rear rim after the brakes were applied.

I also found a small bow on the rim.

I got it evened out using a pair of Vicegrips.
It is softer material than I would have expected.

They are Silverseal and I tried to find out what they are made of with
no success.

Andy