Re: TR3 Type "A" front brake caliper rebuilding
hondo402000 said:
they should come apart, it would be difficult to maching the piston bores with a one piece unit,...
Hondo
The original TR3 calipers are one piece units. They have a big threaded plug on one side to facilitate the machining.
Also, as mentioned above, make sure you get both grooves in each bore very clean of all dirt and rust, or assembly will be difficult and seals may get cut when the piston is pushed in. I've found that running a dental type pick or scribe around the grooves works very good for loosening up the dirt and rust, followed by some wire brush work. Alternately, if you have access to a glass beader, that would be ideal.
Edit: I see you posted while I was still looking for a picture of the A style calipers.
Yes, the the insides of those bores and grooves look very good. Definitely a candidate for rebuilding. Don't worry about any "staining" or pits in the bores, as the seal seals on the outside of the pistons and in the seal groove.