Disc and Drum Machining Clayton South

Disc and drum machining

Cutting a worn surface true again, when there is enough metal to do it.

Service One Automotive machines brake discs and drums at Factory 9, 266 Osborne Avenue, Clayton South VIC 3169. Machining cuts a worn or uneven friction surface back to true, which cures a shudder without the cost of new parts. It is only possible when the disc or drum is thick enough to lose the metal, so everything is measured first. Ring or text 0434 949 091. Please call to confirm current weekday hours.

What machining actually does

A disc starts life perfectly flat and perfectly even in thickness. Heat, wear and rust take that away, and what you feel through the pedal is the pads grabbing and releasing as the uneven face turns.

Machining puts the disc on a lathe and takes a fine cut off both faces until they are flat and parallel again. The shudder goes because the cause of it has been removed rather than covered up.

It is a measurement, not a preference

Every disc carries a minimum thickness stamped on it, and machining only ever removes metal. So the question is simple arithmetic: is there enough left above the minimum to take a cut and still have service life afterwards?

If there is, machining is the cheaper answer. If there is not, we will tell you so rather than take the cut anyway. A disc machined down to its limit overheats, fades and comes back as the same shudder within months.

Drums, and why they are different

Drums wear from the inside out, so they go oversize rather than thin. The limit is a maximum diameter rather than a minimum thickness, and it is stamped on the drum in the same way.

Older cars and the rear of a lot of small cars still run drums, and they respond well to machining because the surface is protected from the weather.

Having it done here

It is done on the premises, so a set of discs does not have to go away and come back. That matters most when the car is already in the air for a brake job and you would rather not lose a day to it.

Machining is worth asking about when

The steering wheel or the brake pedal shudders as you slow from speed
There is a visible lip around the outer edge of the disc
The car has sat for a long time and the discs have surface rust and pitting
You are replacing pads and want the new ones to bed onto a true face
A brake job has been quoted as new discs and you would like the numbers checked

Questions about disc and drum machining

Is machining as good as fitting new?

For a disc with plenty of thickness left, it gives you a true face and a proper bed in for new pads. For a disc already near its limit it is a false economy, which is why the measurement comes first.

Can you machine discs while I wait?

Ring and ask when you book. It depends on the car and on what else is in the workshop that day.

Do discs have to come off the car?

For machining on a bench lathe, yes. Tell us what the car is doing and we will tell you what is involved for yours.