This will darken the metal so you can see how close you are getting to the cutting edge.
Grind the relief just back of the cutting edge, and up to within .005 to .010 of the cutting edge. It won't
take much to give the necessary relief, as all you need is clearance so the reamer won't rub.
STONING THE CUTTING EDGE
Once the face has been honed, it will be necessary to hone the flutes. Hone right up to the edge
watching the lay out fluid coating. This will tell when you have got it honed tight.
Start from the area where you ground the relief, and slowly go up to the cutting edge. It should feel sharp
when completed.
ATTACHING THE PULL ROD
When you have both honed, it is time to sweat the pull rod to the reamer. It is best to use a 1/4 inch drill
rod for this purpose, as it is smooth and uniform. Clean out the 1/4 inch hole in the reamer with some
rolled up emery cloth, then put some paste solder in the hole. Insert the drill rod into the hole, and heat
the shank up until the solder melts.
When it melts, rotate the drill rod in the hole to get a good tinning job. Let cool and job is completed.
This is one important reason for stress relieving the reamer while heating in the furnace. If the reamer
warps then it will be crooked on the pull rod, which in turn will cause a rough and oversize bore.
Before using the reamer the first time, recoat the flutes and cutting edges with the layout fluid. The
reason for this is that when you use the reamer the first time. If it gives you trouble the lay out fluid will
show up any rub spots, and any place you do not have enough clearance.
The main problem that you may experience will be chatter.
A new reamer has more tendencies to chatter than one that has been used for some time. Chatter may
often be reduced by closer fitting pilots and guide bushings, or reducing the speed, also sometimes
increasing the feed will eliminate chatter. If for some reason there should be to little clearance, the
reamer will not cut freely, as the lands or margin will rub instead of cut against the walls of the barrel. In
most cases the reamer will either lodge or break off a flute or two, or break off. In the case of a finish
reamer, the barrel will be ruined. This is why I always soft solder the pull rod on, rather than fastening it
on solid.