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Old 07-10-2017, 11:21 AM
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Tuning up a Rock BR - Updated

5. Now make or buy 2 Delrin(UHMW) washers with the appropriate diameters. These washers will replace the bearing discarded in step 4. See photo below.


6. Lightly lube the main adjustment screw and reassemble the upper cross slide assembly. Now is the time to position the thrust bearing if you have decided to use them.

As you assemble the cross slide be sure to adjust the backlash.
You adjust the backlash by how tight you set the nut holding the whole assembly together. Trial and error with this adjustment. Look under the mariners wheel at the end of that funky arrow in the photo below.


7. Assemble the upper assembly to the base assembly using the Delrin washers as shown. The smaller washer goes on the main adjustment screw. The larger washer goes on top of the gross adjustment post. An appropriate sized thrust bearing could replace either of the Delrin washers.

Smaller washer on the shaft.
Uparts 12.jpg

Larger washer on the gross adjustment post.
Uparts 13.jpg

Throw away that black part that locks the height adjustment. Itís inside the main casting, behind the mariner wheel lock screw, and presses against the adjustment shaft. That is the thing that causes the rest to not lower smoothly when you turn the mariner wheel.

Thatís about it for the adjustment mechanism.
The older I get, the more grateful I am.......
William (Bill) Powell
Cave Creek, Az.

Last edited by Bill40718; 07-10-2017 at 01:29 PM.