I was watching the other replies, no one seemed to pick up on the fact
that you misstated the the difference in sizes. The schedule 80 is
indeed 1.90" but the axle stub is 1.750" or .150" smaller (10x larger
play than the .015" listed in your post). That will indeed require some
sort of shimming or massive plug welds to accommodate the misfit.

mark wrote:
My local trailer building supply house has "high speed stub axle
assemblies" with a stub 4"long and 1/3/4"in diameter made so you can
build your own axles. I assume they are designed to go into some type
of pipe or tubing and welded in place but what kind. The u bolt spring
hangers they sell are for 2 3/8"dia . This leads me to believe maybe
2"schedule 80 pipe which is 2 3/8"OD but 1.90"ID. Is 0.015" play too
much, should they be wrapped with shimstock? There is 2 3/8"tubing
available but the ID is 1.749" so they won't fit that. The seller
(princess auto) has no idea either. Thanks