MAHLE RTI BRC450 - Manual (Page 10)

Page 8
V. Cutting Brake Rotors/Discs
A. Installing the Cranks and Centering Plate. (See Figure 4 ) The standard set-up uses the standard
Centering Plate and 90 mm long Cranks. Note that on the outside of the Centering Plate, next to each
hole are the stamped numbers “3",” 4", or “5". For 4 lug hubs, you insert (4) Cranks from the side
opposite the stamped numbers into the (4) holes marked “4". For 5 lug hubs, you insert the (5) Cranks
into the (5) holes marked “5". For 6 lug hubs, you insert (3) Cranks into the (3) holes marked “3". Then
install the washers and nuts finger tight on the studs of the Cranks. The legs of the Cranks should be
all pointed in the same counter-clockwise direction. (See Figure 1) Place the large holes in the legs
over the hub studs and install the lug nuts finger tight, or as appropriate place the holes in the legs in
line with the threaded holes in the hub and install the lug cap screws finger tight. Then tighten the lug
nuts or cap screws to the vehicle manufacturer’s recommended wheel installation torque.
B. Installing the Cranks and Centering Plate (See Figure 5) The optional set-up, sometimes required
for 4WD applications where the hub sticks out more than 90 mm (3 ½") uses the optional deep 3/4/5/6
Centering Bell. The use of the Centering Bell alone increases the clearance available by 35 mm (1-
3/8") to a total of 125 mm (4-7/8"). Note that required clearance can be sometimes reduced by
removing the hub cap. The additional use of the 10 mm spacers under the legs of the Cranks provides
135 mm (5-5/16") of clearance which is more than enough for almost all 4WD vehicles. By substituting
the optionally supplied 104 mm (4-1/16") Cranks, the clearance can be extended to 139 mm or as
much as 149 mm (5-13/16") for the rare 4WD applications that may require this. Note that the
Centering Bell provides for the use of (6) Cranks for 6 lug hubs so as to better support the lathe when
it is further away from the hub. Note also that there is a special optional 7 Lug Centering Bell available
for the new Ford trucks. Installation of the Cranks in the Centering Bell and onto the vehicle hub is the
same procedure as described above for the Centering Plate.
C. Vibration Dampening. The BRC450 comes with a Vibration Dampener rubber ring. This should be
installed onto the largest outside diameter of the rotor. There are many other types of vibration
dampener types, including a device using two (2) rubbing blocks. On any rotor some type of vibration
dampening device is recommended to avoid excessive high pitched noise or vibration when machining
the rotor.
D. Install the Lathe (See Figure 1) First, be sure that the cutting tool holders are pulled back beyond
the tool slide. This is accomplished by operating the feed handwheel manually. Then install the lathe
onto the Centering Plate or Bell by first inserting the guide pin on the Centering Plate/Bell into the hole
in the center of the lathe spindle. By rotating the Centering Plate/Bell, engage and tighten the
Centering Plate/Bell’s female threads onto the male threads of the lathe spindle until the threads
bottom out. Now install the adjustable cane onto the handle nearest the tool slide, and adjust the length
so that it touches the floor, supporting the lathe from swinging around the hub axis. Then, loosen the
axial adjustment clamping screw and adjust the axial tube in or out as necessary to position the tool
slide so that the center of the rotor is nearly exactly in the center of the tool slide. Tighten the axial
adjustment clamping screw.
In some cases, during installation, the lathe will need to be rotated to position the tool slide near the
section of the rotor where the caliper was mounted. In order to do this, remove the safety pin on the
Transport/Setup Lift and loosen the locking handle on the platform tube. Then re-tighten the locking
handle when the lathe is in position.