CONNECTING ROD PIN END – BORING
In certain cases, we have to remove a good deal of stock from the pin end of the rod. Whether to fit oversize pins in a press-fit rod, to fit bushings that are .001-.002” oversize or bore out an undersized bushing to spec, this can be hard work without the right equipment. For shops without a boring machine, using the thin honing stones can prove to be very costly, as the stones are not cheap, wear fast and tend to crumble under any amount of pressure. In cases like this, we use a 1-1/2” wide piece of emery cloth from either a sanding roll, or we’ll just cut strips from used (aluminum oxide) sanding belts. We cut a 6-8” strip and wrap it around the mandrel. When honing steel, an 80-grit or coarser belt will remove material quickly (up to .001” per second, in some cases) so use caution when getting close to size. For bushings, the 80-grit works well to remove excess stock, but will leave a rough finish. It’s best to finish and smooth out the last few thousandths with a 240-grit or finer cloth, which will leave a smooth finish.
Miles Rogers
BP Rods
Magnolia, TX
February, 2017