06-25-2012, 02:14 AM
Hello Ron,
My "similar job" wasn't for a crankshaft but it was for a fit between a tapered hole and length critical pin in an experimental precision fuel pump, the hole had been accurately bored but was too rough to get a friction lock on the taper and didn't seem very square to the working surface, the lap was made from a piece of car axle, it was what I had and pretty hard, and was set up much like the pictures above, and after a few seconds of running the high spots were knocked off, a friction lock was possible and the pin didn't wobble any more, the taper on the lap was cut without moving the compound setting after turning the actual "crankpin" (although it wasn't really a crankpin as such)
Sorry for no pictures this was ten years ago when working in an R&D facility, where cameras were not allowed for patent security reasons, It was just a day's work, so I probably would not have taken a photo anyway.
Best regards
Rick
My "similar job" wasn't for a crankshaft but it was for a fit between a tapered hole and length critical pin in an experimental precision fuel pump, the hole had been accurately bored but was too rough to get a friction lock on the taper and didn't seem very square to the working surface, the lap was made from a piece of car axle, it was what I had and pretty hard, and was set up much like the pictures above, and after a few seconds of running the high spots were knocked off, a friction lock was possible and the pin didn't wobble any more, the taper on the lap was cut without moving the compound setting after turning the actual "crankpin" (although it wasn't really a crankpin as such)
Sorry for no pictures this was ten years ago when working in an R&D facility, where cameras were not allowed for patent security reasons, It was just a day's work, so I probably would not have taken a photo anyway.
Best regards
Rick
Whatever it is, do it today, Tomorrow may not be an option and regret outlasts fatigue.