On Sat, 7 Jun 2008 21:24:19 -0500, "Karl Townsend"
wrote:


...
pretty straight forward, but the pointy end is supposed to be for finding
the center of holes, but for the life of me I cant seem to figure out how
this is supposed to work.

Does any one here know?

I was hoping somebody would give a better answer than mine. Seems you're not
getting an answer.

I've not seen anybody else do this, so there may be a better way. On a very
small hole, the pointed end will tell you which side you hit first as you
lower the quill. Make an adjustment and try again. When you're all the way
down, you're right over the center of the hole.

Karl


The point of an ordinary scriber fitted in the chuck can be
used to locate an edge, a scribed line or a centre punch dot.
It's pretty rough and ready because the point can be a bit cock
eyed and not accurately represent the true spindle axis.

The pointy bit of the edge finder set is intended to do the
same job but eliminate the spindle axis error.

Set the pointer end roughly on axis and close to a flat
surface. Run at any convenient low speed and with a finger
resting on the surface SLOWLY edge the point in until the point
reaches dead centre and no longer rotates around a small circle.
The point is now dead on the axis of the spindle.

It's pretty easy to learn to do this and it only takes
seconds. It's then a versatile location finder.

This is the way it is supposed to work but the downside is
that it means removing the cutter and replacing it with the edge
finder. A more convenient kludge is the "sticky pin" system.

In ancient UK terminology a gramophone needle is stuck to
the end of the already installed cutter with a lump of
Plasticene. The point of the needle is then centred by finger
pressure. It needs a little more skill to do this because, until
you're used to it, both ends of the needle may initially be way
off centre. However it's a skill well worth aquiring as it's very
much quicker than messing about changing between cutter and edge
finder.

Not sure about the North American equivalant. Gramophone
needles are pretty rare now but the cut off end of a thick sewing
needle does the same job.

Plasticene is a propriety brand of modelling clay which
happens to have sufficient "stickyness" without being "rubbery".
This zero "rubbery" is vital as the point mustn't spring back
once it's centred.

Jim