On Tue, 26 May 2020 12:02:56 -0700, Bob La Londe
wrote:

On 5/26/2020 8:38 AM, Jim Wilkins wrote:
"Bob La Londe" wrote in message ...
I've had decent luck with the cobalt drills from HF as well, but to be
fair I've had ok luck with their cheaper drills as well.

==============================

In steel?


Yes. Although that's so broad its not really a question. 1018 isn't
much harder than aluminum, and I'd challenge any steel drill to punch
holes in harder alloys for very long without burning up. (I do have
some carbide drills, but I mostly use them for aluminum.)

On a project making 304 stainless steel pens (multiples) a couple years
ago I was able to drill out more bodies per sharpening with Precision
than with HF drills, but out of the box the HF was sharp and the
Precision Twist Drill just rubbed.

The HF would drill about 3 bodies (both halves) and the Precision would
drill 6-10 (both halves) before needing to be resharpened. Yes, better
drills are better, but a properly ground drill actually drills.

One thing I have noticed is its hard to resharpen small drills, and a
lot of the small drills (from several brands) don't look all that sharp
under the glass.
Last time I was in HF I picked up a couple packs of TiN coated small
bits. Last evening, second son wanted a ball stud for a custom mount
so I grabbed a ball bearing and held it at cherry red (as hot as the
propane torch would get it) for a few minutes. After it cooled I put a
dimple in it with a diamond burr then one of these bits went through
it like cheese, then drilled to size and silver bazed in a section of
bolt for a shank. Son was very pleased with the end product.
Now that I know I can drill ball bearings, I will have to come up with
more ideas.