C3 Caliper Refinishing

[Steve M.]

I am doing a frame off on a 1969 convertible and have a question on the machined surfaces on the calipers. I have reviewed quite a few Forum questions and still could not find a definitive answer. I understand that the 'machined' areas are not painted. The areas that I see are: hose connection, bleeder screw, bolting areas and 4 'half moon areas'. The area on the top of the caliper where the pin joins the 2 halves together is the area of my question. The flat area across the top looks like it is ground and not 'machined'? Is this area not painted?
Thanks Steve

[Terry M.]

Re: C3 Caliper Refinishing

Grinding, like milling, broaching, and drilling, is a machining operation. The area around the pin is machined. When we wrote that paragraph we deliberately used the term "machining" so as not to focus on a specific operation, but rather describe the general process of smoothing the surface of the casting.

[Patrick H.]

Re: C3 Caliper Refinishing

Steve,

These photos should help.

Patrick

[Michael G.]

Re: C3 Caliper Refinishing

Patrick, Is that the original finish and is it safe to say it was "brushed on" before machining? The inner portion of the caliper half looks to have a "drip" appearance.

[Patrick H.]

Re: C3 Caliper Refinishing

These were NOS caliper halves, and since I was too cheap to buy them I photographed them instead.
I suspect that it was sprayed poorly based on the drips.

[Joe L.]

Re: C3 Caliper Refinishing

Patrick, Is that the original finish and is it safe to say it was "brushed on" before machining? The inner portion of the caliper half looks to have a "drip" appearance.

Michael------


Rarely, if ever, were chassis components brush-painted. They were either sprayed or dipped.

In the case of brake calipers, the castings were painted prior to any machining. So, any machined areas were free of paint.