Choosing an on-car rotor resurfacer. (brake repair)

Choosing an on-car rotor resurfacer

For a number of years now, on-car brake lathes and grinders have been gaining acceptance as an alternative to resurfacing brake rotors on a bench lathe. Though views differ on the relative merits of on-car versus off-car rotor refinishing, proponents of the on-car technique say their methods can save time, trouble and expense on many applications.

In particular, Honda and other Japanese front-wheel drive cars are prime candidates, where the rotors are mounted on the backside of the wheel bearings, making removal the equivalent of major surgery.

Anybody who's undertaken one of these jobs knows what a pain it is to remove the knuckle so the wheel bearings can be pressed out and replaced. What's more, the added labor and cost of extracting and reimplanting the wheel bearings just to refinish the rotors off the car adds considerable expense to what would otherwise be resurfacing got its start.

With the advent of composite rotors in recent years, on-car resurfacing received another boost. Composite rotors in recent years, on-car resurfacing received another boost. Composite rotors are not as rigid as their one-piece cast counterparts, so they're more sensitive to runout problems and vibration. When a composite rotor …