Brake rotor runout - truing front hubs

[burgermeister]

When I installed new rotors on my kit car, I seemed to need more brake pedal travel. At least one of the possible reasons is rotor runout, which I measured at .007". Not caused by the rotor, but caused by the hub and a mix of zinc paint and rust depositions and galvanic corrosion.

I was able to make an arbor and true the hub on a South Bend 9A, and rotor runout is .001-.002" now.

The kit car has 4 piston calipers and does not have power brakes, so pedal travel is at a premium. I want as little as I can get!

An alternate method, which I think was used on the kit car initially, is to install Hawk Blue pads or similar and drive around for a few hundred miles. I image that will machine the runout away also.

[Zuffenwerker]

Galvanic corrosion is a real problem! Love your solution and your south bend. Looks like you are a handy machinist. The arbor and tapered cones are trick. Especially the threaded end to draw the cones into the hub

[Dpmulvan]

I have a southbend 9a decent little lathe, burger do you have the metric change gears? Was wondering how well they worked. Just wish I had another inch or two of swing to resurface heads.

[burgermeister]

Originally Posted by Dpmulvan

I have a southbend 9a decent little lathe, burger do you have the metric change gears? Was wondering how well they worked. Just wish I had another inch or two of swing to resurface heads.

I do have them, but honestly I have never used them. Since the thread dial won't work, seems it would be a PITA to do metric threading. In general I use a die holder to thread, it works reasonably well up to 3/8" or 10mm. Beyond that holding the stock becomes difficult for my chuck.

I agree, the 9A is a lovely machine but a tad small. Something 12" would be much nicer to have. Alas, room and transport becomes an issue. The 9A breaks down into carryable parts in 30 minutes.

Mine dates to the early 40's.