Grinding (turning) a brake disc, in situ

Lathe “VBG 600” and the SAAB/GM 108/4--110/5 connecting plate were used in the development of this method.

Raise the car and remove the wheels on both sides.

Important
It is important to remove both wheels so that vibration will be eliminated and also to raise the car horizontally so that lubrication of the transmission will take place correctly.

If the work is carried out in the order front right, front left, rear left, rear right, then basic adjustment of the lathe will be facilitated.

Remove the brake caliper without disconnecting the brake line and suspend the caliper by means of a cable tie, see

and

Check the brake disc, see

and

Clean the mating surface between the brake disc and the connecting plate.

Fit the tool for runout compensation (accessory 25) in the brake caliper bracket.

Fit the connecting plate with the wheel studs.

Tightening torque: 30 Nm (22 lbf ft).

Back off the adjusting screws.

Clean the mating surface and mount the lathe on the connecting plate. Connect the lathe to a mains supply.

10.

Connect the arm with the dial gauge resting against the runout compensation tool.

11.

Start the lathe and note the highest and lowest readings. Switch off the lathe.

12.

Adjust one of the four adjusting screws and repeat points 9 and 10 until the variation is less than 0.08 mm (0.003 in).

13.

Remove the arm with dial gauge and the runout compensation tool.

14.

Adjust the turning tools against the disc with the tool holder. Remove the locking screw and move the holder.

15.

Set the automatic stop.

16.

Feed out the tool holder and manually grind off the outer and inner rusty edges.

17.

Set the turning depth and switch on automatic operation.

18.

Check the brake disc.

19.

Remove the lathe. Remove the connecting plate.

20.

Fit the brake caliper, see

and

21.

To grind (turn) the other side, the lathe will have to be turned upside down.

22.

Grinding (turning) is then carried out as described above.