> I could never get the bars adjusted to not have some
> taper--as the bar extends down the bore a lot more bar gets on the wobbly
> side of the bushing. Single point cutter and a long bar equals tapered hole.
FWIW, one of my lathe books shows an "improved" setup for boring cylinders.
It's a rather large diameter, apparently hollow bar, with a fixed rather than
movable bushing so the length of bar outside the bushing remains constant. They
also used a dual-point boring head on the bar. The description is for boring
small single-cylinder engines, but I don't see why the same thing wouldn't work
for a TRactor motor liner.
The other thing that comes to mind is mounting the boring bar between centers.
The setup would be a bit tricky, getting the liner mounted just right on the
cross-slide, but I'll bet it would be more repeatable than a long, unsupported
bar. And again, using a bar around 3" in diameter would help rigidity too.
Randall
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