Datsun Roadster Forum-311s.org

I lent a brake rotor to a mate and got it back blued and maybe ruined. (??)

If the metal has been over heated to be blued, is the rotor beyond use?

If so, I need a replacement since that was one of my two back up rotors.

If it's ruined, any one have a good used rotor they would part with?

cheers
tim

They are cast iron and will handle an amazing amount of heat. Check for warping and it should be fine.

keith0alan wrote: Sat Oct 28, 2023 8:17 pm They are cast iron and will handle an amazing amount of heat. Check for warping and it should be fine.

I should have mentioned that, using a straight edge, is appears to no longer be flat. I've not used any actual measurement tools but a straight edge shows what is shows.

Do some measurements as to thickness and warp. It is quite likely that once turned straight is will be too thin.

The trouble when they turn blue is
It hardens the steel and the cutter bit will not cut smooth ...it skips
On drums ,$$$ ones. a machine shop can grind it out... also its called a dull spot, which grabs the brake material way more than clean cast iron and will pulse the brakes

I agree with other in that if it has a blue hue to it, it got real hot and at a minimum is probably warped. If it is still safely within the minimum thickness spec and is not heat checked, there is a possibility it can be resurfaced. Machine shop with experienced guys will be able to tell you if it will turn out.