There was an artical in "Model Engineer" somewhere in the last twenty years on reamers and using a wood strip to expand the hole.
With the tool makers reamer, if you sharpen it with a stone it will get a little burr on the cutting edge, this can be left on to enlarge the hole, If the tool is hardened properly, this burr will be only tenths of a thou. For one off holes in brass and aluminium, you don't even need to harden it, a bit of the shaft you'r going to use ground off at about 20*, put it through once, try for size, If it's still too tight' (unhardened)file the face, this will throw up a burr.
Ian S C