In article , Robin S. says...

Peck lightly and don't press the drill hard enough to bend it.

Do you frequently feel your drills bend?

No, you *see* them bend. When I was drilling that
deep hole in the nickel-iron tubing, I didn't want
the material to work harden - so I was pushing the
drill pretty hard. When I went too far it went
beyond the column limit and bowed out a tad...
so I backed off a bit.

Use a brand new
drill.

Most HSM's have unlimited budgets and time to buy new tooling whenever
required.

I find you never achieve such evenness of flute width and accuracy of
cut on a resharpened drill as you do with a new high quality one.

Perhaps you need to resharpen more drills.

Honestly for this one I have to agree with Dave here. There
is simply no way I would be able do do as good a job as Gurhing
with pointing one of their drills. That the holes came out
as good as they did (about two thou out over an inch) I attribute
mostly to their drill sharpening prowess.


I can see the necessity for new tooling in a production setting but for the
HSM and frequently in tool shops, one drill could be sharpened ten times
before it shatters and another one is used.

For larger drills, yes. But for the smaller ones (and remember, I'm
advocating pilot-drilling deep holes) there is no way the HSM can do
as good a job as the manufacturer.

Jim

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