Enlarging a bushing hole?

On Mon, 27 Aug 2007 17:51:37 -0700, "Rich S."
wrote:

"Michael Horowitz" wrote in message
.. .
I find myself having to enlarge a bushing's ID by 1/16ths to 3/8ths.
My concern is I don't know how to insure the 3/8" bit is aligned with
the axis of the hole. Centered is good, but I'm more concerned with
the alignment.
Suggestions? - Mike

Chuck a rod in the drillpress the same size as the existing hole. Slip the
bushing on the rod and clamp it to the table. Replace the rod with your new
drill or reamer. Make shavings.

Rich S.


And what if the hole is whollowed out such that rod or any drill bit
you have doesn't touch the bushing walls evenly? - Mike

"Michael Horowitz" wrote in message
...
On Mon, 27 Aug 2007 17:51:37 -0700, "Rich S."
wrote:

"Michael Horowitz" wrote in message
. ..
I find myself having to enlarge a bushing's ID by 1/16ths to 3/8ths.
My concern is I don't know how to insure the 3/8" bit is aligned with
the axis of the hole. Centered is good, but I'm more concerned with
the alignment.
Suggestions? - Mike

Chuck a rod in the drillpress the same size as the existing hole. Slip the
bushing on the rod and clamp it to the table. Replace the rod with your
new
drill or reamer. Make shavings.

Rich S.


And what if the hole is whollowed out such that rod or any drill bit
you have doesn't touch the bushing walls evenly? - Mike

You can use a light weight rod and bend it slightly, so it traces the OD of
the hole, as the shaft rotates.

Machine shop supplies sell a "wiggler". It chucks in a drill or mill and has
a pointer about 2 inches long mounted on a ball. The ball fit allows you to
bend it easily, and many times over in daily use. But bending an 1/8 welding
rod will perform the same function, if you are patient with bending it.

"Michael Horowitz" wrote

And what if the hole is whollowed out such that rod or any drill bit
you have doesn't touch the bushing walls evenly?

Depends on the style of bushing, and if it is installed in a larger
structure, at present.

If it is bushing with a flange, level the drillpress table, by chucking the
rod, then using a good square to get the table perpendicular in all
directions; then clam the bushing and drill.

If it is without flange, and rather tall, chuck up rod, get bushing clamped
so that the outsides of the bushing is parallel to the rod, and drill.

If you have access to a lathe, chuck the bushing, and tailstock drill it.
--
Jim in NC