I just spent a couple of hours getting a cast-iron bush to fit a reamed hole, also in cast iron. I had a good finish and finally it fitted all the way in with, I thought, only gentle persuasion.
Then it stuck. I spent another half hour separating the bits and now have a ragged tear in the bush (though the bore is still fairly smooth). I doubt I'll be able to get it back in the 4-jaw sufficiently well centred to clean it up.
What did I do wrong ? Should I have lubricated it ? Or not tried for such a close fit ? I might have expected soft aluminium to grab but I thought cast-iron was hard and slippery.
-adrian