Redrilling 56mm Banebot Carrier Plates

:slight_smile: For those of you that want to be sure you have good carrier plates, and don’t want to spend the money on the new transmissions to get them, I recommend the following:

Remanufacture the hardened carrier plates with the short pins, and drill/ream using a 5/32 inch or #22 drill/reamer, depending on the press fit interference you desire, new holes in between the existing holes. 4mm x 16mm long pins were available at Atlantic Fasteners, West Springfield, MA. These have a chamfered and a rounded end. Press the pin through the hole (chamfered end) to the correct height (15mm). Grind off the end protruding through the plate, which also removes most of the chamfer for a better engagement in the hole. Locktite designed for a press fit can also be used. You can drill the holes easily with a CNC machine with digital readout. Center the arbor in the Double D hole using an edge finder. Center to the radiused surfaces first, and then to the flat to establish X and Y zero in absolute programming mode. The following are the coordinates for each of the five holes, starting at 3 o’clock position, and progressing in a clockwise direction for the rest. It would be recomended that you double-check my coordinate values, and run a test part, before attempting this on your hardened carrier plates. I would also suggest using a cobalt drill, but HSS should work with oil and slow drill speed. I also suggest making a bushing 15mm long, with a sliding fit for 4mm to help ensure that the pins are driven square into the carrier plate, and all are the same height.

Coordinates:
x0.7087 y0.0 (3 o’clock)
x0.219 y0.674
x-0.5733 y0.4165
x-0.5733 y-0.4165
x0.219 y-0.674

Pin Center diameter 36mm. Calculations done at radius of 18mm, or 0.7087 in.

I can confirm your coordinates. They match the ones that I made earlier in the season, which have been running fine in our gearboxes since the end of January. Center carefully! I cut whole plates on a waterjet, so I didn’t have to worry about that, but that is what will throw your alignment off and cause binding.

Thanks for the confirmation of the coordinates, and confirming functionality. Centering is the key to a good part, which is why I emphasized edgefinding the radius first (and centering on that axis), and the flats second, to center the Double D. I was hoping to give teams a way to improve the carrier plates they were sent by Banebots to eliminate the loose and short pins, without having to make the double D hole, since those plates were available to everyone.----:slight_smile: