Bearings don't fit (Drill rod) shafts ?

[yarb65]

45 auto has the correct answer. We have when in a pinch used the drill press and emery cloth technique.

[de_]

Thanks you guys. Its now clear what is going on and where I should have bought the rod from (and will in the future). Will try emery cloth or file (good safety tip) on our lathe for our 2 short term needs. If not a solution (rod too hard?), will buy the correct rod.

We need more mech guys on our team

[Dick Linn]

Taking a couple thou off an end of the unhardened drill rod shouldn't be hard if you can hold and spin it properly. We once had to open up two drive sprockets from 5/8" to 16 mm, or make the hole about .005" larger. It took a very long while with a 5/8" stub in the mill-drill and lots of valve grinding compound. Reducing a shaft diameter is a LOT easier. You can glue the emery paper on a stick and use it like a file.

I have had ground shafting come in oversized and even crooked.

[de_]

update: We used emery cloth to downsize two drill rod shafts say 8" long and 2 out of 2 shafts appeared to be microscopically "bent" when installed on our shooter between 2 brand new bearings. The center of the shaft moved up and down when hand rotated even though it had never been run under power. All I can think of is the drill rod surface hardness was not consistent and the emery cloth wore down parts of the surface faster than others.

Next year we buy the correct shaft rod from McMaster Carr. And find a machinst mentor