There are advantages to using split-point drills, Bob. It's likely that
you've heard or seen the following comments before, but I'll include them
for others to ponder.
Some advantages of split-point drills may not be considered to be cost
effective for some users, and the advantages may be somewhat over-emphasized
by drill sharpener makers and some mis-informed users.

I know that a lot of drill users are unaware of how easy it is to create
split points on on common twist drills, though.
Many users believe the split is created by cautiously sneaking up on the
center of a drill point with a gouging-type grinds, after the cutting faces
have been ground, with the impression that if the grinds aren't perfectly
centered, the drill needs to be reground (thus, more time invested in
resharpening).

This method is not how drill makers create split points. The "split" grinds
are done on the back sides of the flutes first, then the cutting faces are
ground normally.. as crowned and relieved or 4 facet, or other popular
grinds.
No ultra-precise machine required to insure that the "split" grinds are
perfectly centered, and no need to nervously sneak up on the center with
gouging-type grinds.

I used to be able to grind very accurate (although not perfect) split points
on drills down to about 1/8" by hand, when my eyes were much younger.

Split-point drills cut efficiently with less feed force and rotational
power. Many hobbiest/handy-types that might use hand drill motors more
frequently for drilling, appreciate that the split-drill point drill is less
likely to wander when starting a hole.

For those users that work with secured, properly positioned workpieces and a
center-punched mark or spot drills with very rigid machines, wandering
drills aren't usually a significant problem. Splitting drill points might
appear to be a waste of time.

That perspective may be different for a user when drilling a lot of holes
with a hand drill motor up on a ladder or some other precarious position.

The primary significance of the split-point drill is that it is cutting from
the instant/moment of contact. This is the reason that split-point drills
are less likely to wander when starting a hole.
Ordinary conventionally-ground drill points are not cutting upon contact.
That chisel section in the web requires force to displace the material being
drilled, enough that the cutting edges can contact the workpiece.
Because the conventionally-ground drill is rotating, the chisel point
doesn't require a lot of force to displace the material before the cutting
edges contact the workpiece, but the force needs to be maintained
continuously for the entire depth of the hole (as there was no existing
hole).
Of course, as the chisel edge in the web dulls, and it will because it's
essentially rubbing a small hole at low SFM, the required feed force
increases, even if the drill's cutting edges are still sharp.
The resistance of the web needing to be forced into the workpiece is the
major difference.

The split-point drill has two cutting edges in the center which are cutting
as a result of the drill rotating, not (as) dependent upon the feed force.

If there are any advantages of using ordinary conventionally-ground drills
over split-point drills, I'd very much appreciate hearing about them.

--
WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html


"Robert Swinney" wrote in message
...
Hey Brian. Not to worry Buddy! AFAIK, the M3 and M5 differ only in that
the M5 includes a Baldor
grinder, web-thinning attachment, and a point splitter. Otherwise, I
think they are basically the
same. I have owned the Glendo version of the M3 for many years and have
been very pleased with it.
It resides in front of my old 1/2" Craftsman bench grinder. Right now I'm
moving the grinder, the
M3, and Glendo's protractor table onto a new 1/2" steel plate. I do most
tool bit sharpening with
the old Craftsman. A new Glendo Accu-Finish diamond grinder is reserved
for carbide tools. It sits
under a microscope.

PS: Re. all the chatter about point splitting: I can't imagine why
anyone with machine tools would
be concerned with point splitting. Web thinning, a distant "maybe".

Bob Swinney