I bought one of the import 4X6 bandsaws some time ago. It was
certainly much better than hacksawing but I was very frustrated by the
blade constantly coming off the wheels anytime I tried an aggressive
cut speed. I tried different blades, different speeds, and adjusting
the blade guide roller bearings as well as the non-driven wheel
height/angle all multiple times but still had the problem
Today I finally got sick of it. I took off the drive wheel and
lathed up a mount mandrel. I used the compound at 5 degrees to cut a
new face on the wheel such that the blade will want to stay on when a
force is applied. Prior to the cut it indicated out as being tapered
the wrong direction by a degree or 2.
Now the saw cuts perfect. If I ask too much of the saw, the blade
will slip on the wheel but it won't self eject. Just a note to the
others if they are having the same problem.

Bill H