A while back I had to drill out a bolt and went through several bits.
Dulling them, snapping them and as a bonus I also snapped a misnamed
easy-out. Buy new bits? Nah, they cost too much for a decent set
besides I have probably 100 drill bits. I gotta figure out a way to
sharpen them.

DAGS. Keeps coming back with buy a drill doctor. I find the thing
from Lee Valley and others that holds the bit at the correct angle to
bench grinder for $10.
http://www.leevalley.com/wood/page.a...072,43086&ap=1

The DD and the angle guide don't seem to be doing anything fancy so I
think why can't I just do it myself. Here's what I'm thinking please
tell me if you think it will work.

Cut a wedge at the proper angle
Chuck the dull bit in my drill press
Clamp the wedge and a stone or fine file to the DP table
Lower the dull bit against the stone or file
Keep bit oiled and cool
Done

Unless I'm missing something doing it that way would give me the same
results as the grinder jig and probably the DD too.

RayV wrote:
snip
Unless I'm missing something doing it that way would give me the same
results as the grinder jig and probably the DD too.

You might get a bit of flex in the drill bit by bringing it down on a
slanted stone - especially with smaller bits.

I received a low end Drill Doctor for christmas last year. I hadn't
bought one for myself because I was skeptical about it. After using it,
I am completly sold on it - great product. Once you are familiar with
using it, it only takes about 30 seconds to sharpen a bit and the bit
is better than new. Definately worth the price (especially when it's
free!!).

Mike

You are missing something, and that something is VERY Important.

What you would end up with would be a drill which would not drill into
even butter, and would burn up if you tried to drill into anything harder.

On a properly sharpened drill bit, only the cutting edge touches what
you are drilling into. That is, that cutting edge extends further out
than the back of the flute that the cutting edge is on. The cutting edge
is the front edge of the flute, and the back of the flute must taper
away from the leading edge. If it does not, then the entire flute rubs
and will not cut.

Like a knife, the cutting edge must be at such an angle to what you are
cutting to dig in, while the side of the knife would just slide over
without digging in to make the cut. The leading cutting edge of the
drill bit works the same way.

The drill sharpening guides are made to automatically cause that angle
to be ground on each flute of the drill bit evenly, and all flutes of a
drill must be at the exact same level, else only one will cut and the
other not touch.

Buy the drill sharpening tools and be happy with the results.

Zap

RayV wrote:
A while back I had to drill out a bolt and went through several bits.
Dulling them, snapping them and as a bonus I also snapped a misnamed
easy-out. Buy new bits? Nah, they cost too much for a decent set
besides I have probably 100 drill bits. I gotta figure out a way to
sharpen them.

DAGS. Keeps coming back with buy a drill doctor. I find the thing
from Lee Valley and others that holds the bit at the correct angle to
bench grinder for $10.
http://www.leevalley.com/wood/page.a...072,43086&ap=1

The DD and the angle guide don't seem to be doing anything fancy so I
think why can't I just do it myself. Here's what I'm thinking please
tell me if you think it will work.

Cut a wedge at the proper angle
Chuck the dull bit in my drill press
Clamp the wedge and a stone or fine file to the DP table
Lower the dull bit against the stone or file
Keep bit oiled and cool
Done

Unless I'm missing something doing it that way would give me the same
results as the grinder jig and probably the DD too.

"RayV" wrote in message
ups.com...


Cut a wedge at the proper angle
Chuck the dull bit in my drill press
Clamp the wedge and a stone or fine file to the DP table
Lower the dull bit against the stone or file
Keep bit oiled and cool
Done

You're close Ray. Forget the wedge and all the other stuff. Take a look at
a brand new bit and notice how the point is ground from flute to flute.
Simply hold the bit against the grinder wheel to achieve the two correct
angles (down and left), and then tail it up until you grind to the second
flute. Easier demonstrated than explained. You don't need any jigs -
besides, they would only be good for one size bit. Practice, examine your
grind carefully, test it on some steel, and if necessary, practice some
more. Forget the oil too. The amount of time a 1/4" bit should be on your
grinder wheel is less than a second per side. If you don't have a grinder a
belt sander will do just nicely.

I sharpen all of my own bits except for the very smallest.

--

-Mike-

"zap" wrote in message
ink.net...
You are missing something, and that something is VERY Important.

What you would end up with would be a drill which would not drill into
even butter, and would burn up if you tried to drill into anything harder.

On a properly sharpened drill bit, only the cutting edge touches what
you are drilling into. That is, that cutting edge extends further out
than the back of the flute that the cutting edge is on. The cutting edge
is the front edge of the flute, and the back of the flute must taper
away from the leading edge. If it does not, then the entire flute rubs
and will not cut.

Like a knife, the cutting edge must be at such an angle to what you are
cutting to dig in, while the side of the knife would just slide over
without digging in to make the cut. The leading cutting edge of the
drill bit works the same way.

I agree with this.

Actually drill bits are not that difficult to sharpen on a bench grinder by
hand once you understand the proper geometry. Apprentice machinists learn
this skill early on.

A visit to your local machine shop with a six-pack in hand might get you a
lesson or two.

--

Roger Shoaf

About the time I had mastered getting the toothpaste back in the tube, then
they come up with this striped stuff.

In article . com, RayV
wrote:

A while back I had to drill out a bolt and went through several bits.
Dulling them, snapping them and as a bonus I also snapped a misnamed
easy-out. Buy new bits? Nah, they cost too much for a decent set
besides I have probably 100 drill bits. I gotta figure out a way to
sharpen them.

Snip
Just do as others have said and start practicing by hand, it will come
to you and and you will never look back.

I have never understood the logic of a Drill Doctor for the average
handy man, for the price of the machine a guy can buy a lot of drill
bits.

FrankC

--
http://sawdustmaking.com

Frank Campbell wrote:
I have never understood the logic of a Drill Doctor for the average
handy man, for the price of the machine a guy can buy a lot of drill
bits.


When I'm working and come across a dull bit, I sharpen it and I'm back
to work in less than a few minutes. If I had to go out and replace the
bit, it would mean a trip to the store. Now, if you do any drilling in
metal, you'd need to buy several bits per project. It might take a
while to recoup the cost of the Drill Doctor, but over a year or two
the machine would pay for itself.

Another downside to replacing bits when they get dull is that you'd be
more likely to keep using a marginal bit until you get out to the store
- whereas with a DD, you can always use a _sharp_ bit every time. It
makes a big difference.

RayV wrote:

Unless I'm missing something doing it that way would give me the same
results as the grinder jig and probably the DD too.


After about the third snapped drill bit I think you'll give up on this
idea. Moreover, as another poster has mentioned, you will be grinding a
cone and a cone can't cut. Period. Not at all.

So let's get you trained to sharpen drill bits by hand so you can amaze
your friends, confound your enemies and have a lifetime supply of sharp
drill bits at your beck and call.

____________________________

Let's start with a two-flute, 118 degree twist drill. No carbide,
nothing fancy at all. It's what you get when you pick up that Vermont
American blister pack down at the local hardware store.

Looking straight down at a new common twist drill bit, you will see that
the end is made up of three straight lines: two cutting lips and a
chisel wedge in the middle. That is, in fact, what each of these edges do.

Notice that the chisel is centered between the two cutting lips. That's
where it NEEDS to be. If its off-center, so are the cutting lips and all
bets are off so far as the resulting hole geometry.

Now look at the drill bit sideways. Notice that the line running
(mostly) horizontally from the edge of each of the cutting lips actually
tilts down and to the left a tad. This is the cutting relief angle and
controls how thick the waste can be. Low angle, slower drilling,
stronger lip. High angle, faster drilling, weaker lip. The relief angle,
also, benefits from being equal for each side although the rate of
penetration is limited by the shallower side so 'close enough is close
enough' (get close, but don't be obsessive about it.

To sharpen:

Dress your grinding wheel flat. Don't even think about skipping this
step. If you don't do it now, you will in a minute as soon as you see
what your drill bit does when bouncing off an out of round wheel while
trying to sharpen a straight edge against a circle with a groove in it
and chunks out of it.

Holding the drill bit up to the wheel, angle it so the shank is to the
right (for the most common twist ... a right hand spiral). Hold it so
that the edge is horizontal. This means that the shank will be dropped
backwards to compensate for the lip angle.

JUST BARELY touch the lip to the stone to confirm that the stone is
smooth and the drill bit is touching across the width of the cutting
lip. Match straight line to straight line. If the drill bit isn't
straight across, balance out the curve. If the wheel isn't straight
across, you didn't do what I told you to in the very first step. Stop
right now, go back and follow the directions. Sharpening drill bits is
pretty easy if you don't try to take shortcuts. If you DO try to take
shortcuts, it's darned near impossible to do a good job ... more so when
first starting out.

Now, with light pressure (until you get a feel for the results) rub the
drill bit against the wheel while simultaneously 1) applying increasing
pressure (this will become your relief angle ... just about 3-5 degrees
is plenty to start with) and 2) rolling the bit between your fingers
while lifting the tip upward. This is the 'skill' part. You need to make
these two motions in concert with each other so as to end up with a
tapered cone / flat spiral that starts with the cutting lip and drops
back slightly at the back of each flute. This is the part your jig could
not do.

Now check to see how you did on this first lip. Be critical of your
results. No slack. It probably looks horrible. See that flat spot right
at the lip and that grind mark on the other lip where you didn't pull
away from the stone in time? That's about par for the course. If it
doesn't look like this, chalk it up to either lax standards or beginners
luck. Experienced people will sometimes get these marks if it has been a
while since they had to sharpen a bit. The key is to hold yourself to
high standards and not quit until you achieve them.

Try again on the second lip. When you check the second lip, also look at
the drill head on to see if the chisel is centered. If it isn't,
re-grind the longer of the cutting lips, being certain to duplicate the
angle on the shorter lip.

It is a good idea to have a water cup handy to quench / cool the tip
after each pass over the grinder. HSS air hardens so we are not too
concerned about the hardness of the steel, but ARE concerned about your
ability to hold a piece of hot metal in bare hands. If it's too hot to
hold comfortably, it's too hot. Cool it. It's a good practice to cool it
after every pass over the wheel but if you are making light cuts, you
may get a couple passes in before things get uncomfortable.

You can buy a cheap drill gauge at pretty much any tool outlet store ...
the General brand is as good as any ... which is to say that none of
them are anything more than approximate. Or you can use a pocket scale
(machinist term for ruler) with fine gradations of at least 1/32 to
measure the cutting lips (when they are the same, the wedge is centered)
and the relief angle (hold the scale horizontally and check to be sure
that the relief is the same -by eyeball- for both flutes. A protractor
with a long arm (again, the General brand is fine) will help you
determine the precise included angle of the lips. To use the protractor,
align one edge with the shank of the drill and the swing arm with the
cutting lip. It should be half of whatever angle you are looking to make
AND the lip should be straight from corner to corner. Profile it against
a good source of light.

Gotchas:

Make certain NOT to round off the corners of the cutting lips. No matter
what the rest of the lip looks like, if the corners are rounded, the
drill is dull. If the corners were rounded during use, continue grinding
until you get past them while meeting all the other conditions above.

Make certain NOT to grind a flat at the cutting lip ... it MUST be the
highest point on the flute. That is, if it is flat, it will rub, not
cut. If it is flat and the other lip is good, you now own a 1-flute
drill which will cut ovals for you. For a while.

You will probably be able to sharpen drill bits down to about 1/8" using
this method. Below 1/8" things get iffy quickly so your best bet may be
to simply purchase a new bit.

Nota Bene:
If you snap a good-sized drill bit (oh, say, somewhere north of 1/4"),
grind the shank off and then, while chucked in our drill press or lathe,
grind a cone on the end. This simple device is useful for 1) marking
where a drill bit will enter work on the drill press or 2) for hand
tapping on the drill press.

To hand tap on the drill press, first drill a hole to the proper size
for tapping then, without moving the workpiece, insert the tapping
center you just made into the chuck. Then place the tap and handle
between the workpiece and the tapping center. Many taps and T-handles
have a recess precisely for this purpose. Then apply light pressure to
the drill press quill while turning the tap with the other hand. Voila!
A perfectly vertical tapped hole!

If the workpiece gets nudged before you can get everything set up, use
the tapping center to re-locate it ... a hole will locate precisely on a
cone.



When I first entered the machine trades I was given a thread gage and
100# or so of mixed bolts to sort. I can tell metric from English and
the various sizes and thread in each group by sight to this day ... and
I haven't worked as a machinist for nearly 10 years.

Right after that I was given about the same weight in dulled drill bits
to sharpen ... and one good drill bit to copy. Total instruction
consisted of "Hold the drill bit about like this ... move it in an arc
about like this. Make it look like the good one. There ya go. Have at
it. Let me know when you think you've got the hang of it."

So practice, practice, practice. And let us know when you think you've
got the hang of it. ;-)

Bill

BTW, to make a flat-bottomed hole similar to one made by a Forstner bit
but without the dimple in the bottom, startb with two drill bits the
same size. Leave one as-is and grind ALL the cone part off the other one
then grind the cutting lips back to get rid of the middle wedge and then
grind a back relief behind the cutting lips. Set your drill press to
make a hole to the finished depth with a regular drill but leave maybe
1/32 or 1/16 of material in the bottom of the hole. The resulting hole
will have straight sides tapering to a point in the middle.

We are going to cut off the tapered part (only) wqith the flat-bottom
drill.

Now change to the flat-bottom bit and reset the drill press to the FULL
depth. With the press off, Lower the flat-bottom drill bit into the hole
to re-locate it. Then turn the drill press on to the same speed as foir
the first bit and finish the hole.

You can pull the same stunt with a tap to tap all the way to the bottom
of a hole. Just keep in mind that when the tap hits bottom it's time to
stop turning it unless you get some sort of perverse kick out of digging
broken taps out of mangled holes. To each his own, I suppose. :-)

Each trade has its tricks. I've been a machinist. Now I'm learning
woodworking.

Frank Campbell wrote:

I have never understood the logic of a Drill Doctor for the average
handy man, for the price of the machine a guy can buy a lot of drill
bits.

I'm with you; however, let me suggest an alternative.

Learn to sharpen bits the old fashioned way.

Take an adult education course at a local school, find a machine shop
that will teach you how do it in exchange for a case of suds, etc.

It is a skill set similar to riding a bicycle.

Once you learn it, you don't forget it.

Lew

"zap" wrote in message
ink.net...
You are missing something, and that something is VERY Important.

What you would end up with would be a drill which would not drill into
even butter, and would burn up if you tried to drill into anything harder.

On a properly sharpened drill bit, only the cutting edge touches what you
are drilling into. That is, that cutting edge extends further out than the
back of the flute that the cutting edge is on. The cutting edge is the
front edge of the flute, and the back of the flute must taper away from
the leading edge. If it does not, then the entire flute rubs and will not
cut.

Like a knife, the cutting edge must be at such an angle to what you are
cutting to dig in, while the side of the knife would just slide over
without digging in to make the cut. The leading cutting edge of the drill
bit works the same way.

The drill sharpening guides are made to automatically cause that angle to
be ground on each flute of the drill bit evenly, and all flutes of a drill
must be at the exact same level, else only one will cut and the other not
touch.

My first job involved drilling little holes into stainless steel. The drill
didn't stay sharp very long, so my first skill was to learn to sharpen them
on a grinder, getting all those little undercuts just right.
Ah, but that was 35 years since I last tried.
How does the machine do it; I thought it was just a simple grinding wheel,
but there must be more to it than that.

Buy the drill sharpening tools and be happy with the results.

Zap

RayV wrote:
A while back I had to drill out a bolt and went through several bits.
Dulling them, snapping them and as a bonus I also snapped a misnamed
easy-out. Buy new bits? Nah, they cost too much for a decent set
besides I have probably 100 drill bits. I gotta figure out a way to
sharpen them.

DAGS. Keeps coming back with buy a drill doctor. I find the thing
from Lee Valley and others that holds the bit at the correct angle to
bench grinder for $10.
http://www.leevalley.com/wood/page.a...072,43086&ap=1

The DD and the angle guide don't seem to be doing anything fancy so I
think why can't I just do it myself. Here's what I'm thinking please
tell me if you think it will work.

Cut a wedge at the proper angle
Chuck the dull bit in my drill press
Clamp the wedge and a stone or fine file to the DP table
Lower the dull bit against the stone or file
Keep bit oiled and cool
Done

Unless I'm missing something doing it that way would give me the same
results as the grinder jig and probably the DD too.

RayV wrote:

A while back I had to drill out a bolt and went through several bits.

So buy some drill bits. They're not expensive, even for decent ones. If
you're drilling something hard, then a set of real M42 cobalt bits is
pricey but wonderful. NB - these are silver, not just a blue coating
(those are worthless).

DAGS. Keeps coming back with buy a drill doctor.

My experience: It was supposed to work except that they mis-moulded a
chuck component making it useless. UK service backup was negligible --
maybe the US is better.

I find the thing
from Lee Valley and others that holds the bit at the correct angle to
bench grinder for $10.
http://www.leevalley.com/wood/page.a...072,43086&ap=1

Great gadget, so long as you set the little nose piece up accurately
and you're working with bits of 1/4" and over.

OTOH, I don't often break 1/4" and I don't even wear them out that
fast. The ones I go through are 3mm - 5mm that I've snapped in half.
Sharpening those is from hard to impossible (if there's no length left).

Huh! I sharpen drill bits on my grinder too. Sometimes I get a good
cutting bit, other times I get a good scoutmaster's fire starter or a great
oval-cutter! This just may help with a little of that trial and error
business I'm so famous for.
I'm gonna put this up over my drill press for next time I need it. Now
if I can only figger how to get that danged point to CENTER :-)!

Good writeup;

Pop`
--
Wrong does not cease to be wrong
because the majority share in it. Tolstoy



Bill in Detroit wrote:
RayV wrote:

Unless I'm missing something doing it that way would give me the same
results as the grinder jig and probably the DD too.


After about the third snapped drill bit I think you'll give up on this
idea. Moreover, as another poster has mentioned, you will be grinding
a cone and a cone can't cut. Period. Not at all.

So let's get you trained to sharpen drill bits by hand so you can
amaze your friends, confound your enemies and have a lifetime supply
of sharp drill bits at your beck and call.

____________________________

Let's start with a two-flute, 118 degree twist drill. No carbide,
nothing fancy at all. It's what you get when you pick up that Vermont
American blister pack down at the local hardware store.

Looking straight down at a new common twist drill bit, you will see
that the end is made up of three straight lines: two cutting lips and
a chisel wedge in the middle. That is, in fact, what each of these
edges do.
Notice that the chisel is centered between the two cutting lips.
That's where it NEEDS to be. If its off-center, so are the cutting
lips and all bets are off so far as the resulting hole geometry.

Now look at the drill bit sideways. Notice that the line running
(mostly) horizontally from the edge of each of the cutting lips
actually tilts down and to the left a tad. This is the cutting relief
angle and controls how thick the waste can be. Low angle, slower
drilling, stronger lip. High angle, faster drilling, weaker lip. The
relief
angle, also, benefits from being equal for each side although the
rate of penetration is limited by the shallower side so 'close enough
is close enough' (get close, but don't be obsessive about it.

To sharpen:

Dress your grinding wheel flat. Don't even think about skipping this
step. If you don't do it now, you will in a minute as soon as you see
what your drill bit does when bouncing off an out of round wheel while
trying to sharpen a straight edge against a circle with a groove in it
and chunks out of it.

Holding the drill bit up to the wheel, angle it so the shank is to the
right (for the most common twist ... a right hand spiral). Hold it so
that the edge is horizontal. This means that the shank will be dropped
backwards to compensate for the lip angle.

JUST BARELY touch the lip to the stone to confirm that the stone is
smooth and the drill bit is touching across the width of the cutting
lip. Match straight line to straight line. If the drill bit isn't
straight across, balance out the curve. If the wheel isn't straight
across, you didn't do what I told you to in the very first step. Stop
right now, go back and follow the directions. Sharpening drill bits is
pretty easy if you don't try to take shortcuts. If you DO try to take
shortcuts, it's darned near impossible to do a good job ... more so
when first starting out.

Now, with light pressure (until you get a feel for the results) rub
the drill bit against the wheel while simultaneously 1) applying
increasing pressure (this will become your relief angle ... just
about 3-5 degrees is plenty to start with) and 2) rolling the bit
between your fingers while lifting the tip upward. This is the
'skill' part. You need to make these two motions in concert with each
other so as to end up with a tapered cone / flat spiral that starts
with the cutting lip and drops back slightly at the back of each
flute. This is the part your jig could not do.

Now check to see how you did on this first lip. Be critical of your
results. No slack. It probably looks horrible. See that flat spot
right at the lip and that grind mark on the other lip where you
didn't pull away from the stone in time? That's about par for the
course. If it doesn't look like this, chalk it up to either lax
standards or beginners luck. Experienced people will sometimes get
these marks if it has been a while since they had to sharpen a bit.
The key is to hold yourself to high standards and not quit until you
achieve them.
Try again on the second lip. When you check the second lip, also look
at the drill head on to see if the chisel is centered. If it isn't,
re-grind the longer of the cutting lips, being certain to duplicate
the angle on the shorter lip.

It is a good idea to have a water cup handy to quench / cool the tip
after each pass over the grinder. HSS air hardens so we are not too
concerned about the hardness of the steel, but ARE concerned about
your ability to hold a piece of hot metal in bare hands. If it's too
hot to hold comfortably, it's too hot. Cool it. It's a good practice
to cool it after every pass over the wheel but if you are making
light cuts, you may get a couple passes in before things get
uncomfortable.

You can buy a cheap drill gauge at pretty much any tool outlet store
... the General brand is as good as any ... which is to say that none
of them are anything more than approximate. Or you can use a pocket scale
(machinist term for ruler) with fine gradations of at least 1/32 to
measure the cutting lips (when they are the same, the wedge is
centered) and the relief angle (hold the scale horizontally and check
to be sure that the relief is the same -by eyeball- for both flutes.
A protractor with a long arm (again, the General brand is fine) will
help you determine the precise included angle of the lips. To use the
protractor, align one edge with the shank of the drill and the swing
arm with the cutting lip. It should be half of whatever angle you are
looking to make AND the lip should be straight from corner to corner.
Profile it against a good source of light.

Gotchas:

Make certain NOT to round off the corners of the cutting lips. No
matter what the rest of the lip looks like, if the corners are
rounded, the drill is dull. If the corners were rounded during use,
continue grinding until you get past them while meeting all the other
conditions above.
Make certain NOT to grind a flat at the cutting lip ... it MUST be the
highest point on the flute. That is, if it is flat, it will rub, not
cut. If it is flat and the other lip is good, you now own a 1-flute
drill which will cut ovals for you. For a while.

You will probably be able to sharpen drill bits down to about 1/8"
using this method. Below 1/8" things get iffy quickly so your best
bet may be to simply purchase a new bit.

Nota Bene:
If you snap a good-sized drill bit (oh, say, somewhere north of 1/4"),
grind the shank off and then, while chucked in our drill press or
lathe, grind a cone on the end. This simple device is useful for 1)
marking where a drill bit will enter work on the drill press or 2)
for hand tapping on the drill press.

To hand tap on the drill press, first drill a hole to the proper size
for tapping then, without moving the workpiece, insert the tapping
center you just made into the chuck. Then place the tap and handle
between the workpiece and the tapping center. Many taps and T-handles
have a recess precisely for this purpose. Then apply light pressure to
the drill press quill while turning the tap with the other hand.
Voila! A perfectly vertical tapped hole!

If the workpiece gets nudged before you can get everything set up, use
the tapping center to re-locate it ... a hole will locate precisely
on a cone.



When I first entered the machine trades I was given a thread gage and
100# or so of mixed bolts to sort. I can tell metric from English and
the various sizes and thread in each group by sight to this day ...
and I haven't worked as a machinist for nearly 10 years.

Right after that I was given about the same weight in dulled drill
bits to sharpen ... and one good drill bit to copy. Total instruction
consisted of "Hold the drill bit about like this ... move it in an arc
about like this. Make it look like the good one. There ya go. Have at
it. Let me know when you think you've got the hang of it."

So practice, practice, practice. And let us know when you think you've
got the hang of it. ;-)

Bill

BTW, to make a flat-bottomed hole similar to one made by a Forstner
bit but without the dimple in the bottom, startb with two drill bits
the same size. Leave one as-is and grind ALL the cone part off the other
one then grind the cutting lips back to get rid of the middle wedge
and then grind a back relief behind the cutting lips. Set your drill
press to make a hole to the finished depth with a regular drill but leave
maybe
1/32 or 1/16 of material in the bottom of the hole. The resulting hole
will have straight sides tapering to a point in the middle.

We are going to cut off the tapered part (only) wqith the flat-bottom
drill.

Now change to the flat-bottom bit and reset the drill press to the
FULL depth. With the press off, Lower the flat-bottom drill bit into
the hole to re-locate it. Then turn the drill press on to the same
speed as foir the first bit and finish the hole.

You can pull the same stunt with a tap to tap all the way to the
bottom of a hole. Just keep in mind that when the tap hits bottom
it's time to stop turning it unless you get some sort of perverse
kick out of digging broken taps out of mangled holes. To each his
own, I suppose. :-)
Each trade has its tricks. I've been a machinist. Now I'm learning
woodworking.

Bill in Detroit wrote:
RayV wrote:

Unless I'm missing something doing it that way would give me the same
results as the grinder jig and probably the DD too.


After about the third snapped drill bit I think you'll give up on this
idea. Moreover, as another poster has mentioned, you will be grinding a
cone and a cone can't cut. Period. Not at all.

So let's get you trained to sharpen drill bits by hand so you can amaze
your friends, confound your enemies and have a lifetime supply of sharp
drill bits at your beck and call.

snip well written sharpening guide

Each trade has its tricks. I've been a machinist. Now I'm learning
woodworking.

Thanks for the explanation, I'll try it by hand this weekend.

So what is the DD and the grinder jig doing? Do they hold the bit at a
compound angle or is it more complicated? The grinder jig doesn't
appear to be doing more than that.

"Toller" wrote in
news
My first job involved drilling little holes into stainless steel. The
drill didn't stay sharp very long, so my first skill was to learn to
sharpen them on a grinder, getting all those little undercuts just
right. Ah, but that was 35 years since I last tried.
How does the machine do it; I thought it was just a simple grinding
wheel, but there must be more to it than that.


(Did you realize your post was between the replies? Top post, bottom
post, but don't play hide and seek, please.)

If you watch the motion of the drill bit in the demonstration, the bit
follows a down, rotate, up type motion. (It's hard to describe simply.)

Puckdropper
--
Wise is the man who attempts to answer his question before asking it.

To email me directly, send a message to puckdropper (at) fastmail.fm

work on one side at a time, obviously the same hand position on each. when
done the geometry on one side is the same as the other. When looking at the
very end you should see a straight line, the "peak" should divide the
geometry exactly, meaning both sides are the same. It needs the angle
measured co-axial from the peak through to the cutting edge, what 118 for
std material, and also some backard clearance, what 9 degrees. In practice
for most wood, if it looks good, and equal, alls well. The cutting lip
should be sharp along its entire path while spinning. Often easier by hand.
Machinery's Handbook tells you how to make the tooling after doing the
calculations for actually making all the geometry correct for something so
simple.



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start with the cutting lip, and sort of spin and up-shove if using a
g-wheel. Its a minor movement. Google.. Actually I don't even know the
right procedure. I use anything handy- like a ut-off wheel on a dremel.
The geometry is gonna cut, or it ain't, precision ain't important for most.
Its freakin incredidble the physics and math that make it what it is to be
what it is though, cuting tools of any type.



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I guess the point is, you can't use the drill press b/c of the stationary
stone, or whatever ,would need to cam in and out while following the flute
while spinning to sharpen. If you look a the construction of bit stock,
though, there is actually a land on the outer edge , so the outside
perimeter has clearance too.



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RayV wrote:
The DD and the angle guide don't seem to be doing anything fancy so I
think why can't I just do it myself.

Reading the DD manual helped out with understanding what it is doing.
The bit needs to be aligned in the 'chuck' The chuck has a cammed ring
that pivots the bit as you rotate it to create the relief angle.
Pretty neat idea.
http://www.genext.drilldoctor.com/PD...rs%20Guide.pdf
I can only assume the grinding jig does something similar.

I'm gonna try Bill's method and see if I can get the hang of it before
I consider a DD.

"Pop`" wrote in message
news:NoH8h.5276$oP6.4447@trnddc03...
Huh! I sharpen drill bits on my grinder too. Sometimes I get a good
cutting bit, other times I get a good scoutmaster's fire starter or a
great
oval-cutter! This just may help with a little of that trial and error
business I'm so famous for.
I'm gonna put this up over my drill press for next time I need it. Now
if I can only figger how to get that danged point to CENTER :-)!

Good writeup;


One of these.

http://72.14.253.104/search?q=cache:...ient=firefox-a

Or : http://tinyurl.com/y3kvwh


--

Roger Shoaf

About the time I had mastered getting the toothpaste back in the tube, then
they come up with this striped stuff.

There is a old trick I always use.... when there is no gage available
you can hold two HEX nuts side to side touching between your thumb and
forefinger for the right angle.( hold up to light with drillbit to
see.)
airbrush

On Tue, 21 Nov 2006 17:58:44 +0000, Toller wrote:

"zap" wrote in message
ink.net...
You are missing something, and that something is VERY Important.

What you would end up with would be a drill which would not drill into
even butter, and would burn up if you tried to drill into anything harder.

On a properly sharpened drill bit, only the cutting edge touches what you
are drilling into. That is, that cutting edge extends further out than the
back of the flute that the cutting edge is on. The cutting edge is the
front edge of the flute, and the back of the flute must taper away from
the leading edge. If it does not, then the entire flute rubs and will not
cut.

Like a knife, the cutting edge must be at such an angle to what you are
cutting to dig in, while the side of the knife would just slide over
without digging in to make the cut. The leading cutting edge of the drill
bit works the same way.

The drill sharpening guides are made to automatically cause that angle to
be ground on each flute of the drill bit evenly, and all flutes of a drill
must be at the exact same level, else only one will cut and the other not
touch.

My first job involved drilling little holes into stainless steel. The drill
didn't stay sharp very long, so my first skill was to learn to sharpen them
on a grinder, getting all those little undercuts just right.
Ah, but that was 35 years since I last tried.
How does the machine do it; I thought it was just a simple grinding wheel,
but there must be more to it than that.

If you're talking about the Drill Doctor the chuck has a cam--as you
rotate it it moves the bit in and out to as to have the flute properly
ground.

Buy the drill sharpening tools and be happy with the results.

Zap

RayV wrote:
A while back I had to drill out a bolt and went through several bits.
Dulling them, snapping them and as a bonus I also snapped a misnamed
easy-out. Buy new bits? Nah, they cost too much for a decent set
besides I have probably 100 drill bits. I gotta figure out a way to
sharpen them.

DAGS. Keeps coming back with buy a drill doctor. I find the thing
from Lee Valley and others that holds the bit at the correct angle to
bench grinder for $10.
http://www.leevalley.com/wood/page.a...072,43086&ap=1

The DD and the angle guide don't seem to be doing anything fancy so I
think why can't I just do it myself. Here's what I'm thinking please
tell me if you think it will work.

Cut a wedge at the proper angle
Chuck the dull bit in my drill press
Clamp the wedge and a stone or fine file to the DP table Lower the
dull bit against the stone or file Keep bit oiled and cool Done

Unless I'm missing something doing it that way would give me the same
results as the grinder jig and probably the DD too.




--
X:\Newsreaders\sig.txt

In article , Bill in Detroit wrote:

So let's get you trained to sharpen drill bits by hand so you can amaze
your friends, confound your enemies and have a lifetime supply of sharp
drill bits at your beck and call.

[snip long and useful lesson]

Thanks, Bill -- that's a keeper.


--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

Yes, you're missing something. Clearance.
"RayV" wrote in message
ups.com...
A while back I had to drill out a bolt and went through several bits.
Dulling them, snapping them and as a bonus I also snapped a misnamed
easy-out. Buy new bits? Nah, they cost too much for a decent set
besides I have probably 100 drill bits. I gotta figure out a way to
sharpen them.

DAGS. Keeps coming back with buy a drill doctor. I find the thing
from Lee Valley and others that holds the bit at the correct angle to
bench grinder for $10.
http://www.leevalley.com/wood/page.a...072,43086&ap=1

The DD and the angle guide don't seem to be doing anything fancy so I
think why can't I just do it myself. Here's what I'm thinking please
tell me if you think it will work.

Cut a wedge at the proper angle
Chuck the dull bit in my drill press
Clamp the wedge and a stone or fine file to the DP table
Lower the dull bit against the stone or file
Keep bit oiled and cool
Done

Unless I'm missing something doing it that way would give me the same
results as the grinder jig and probably the DD too.

"Bill in Detroit" wrote in message
...
RayV wrote:

Unless I'm missing something doing it that way would give me
the same
results as the grinder jig and probably the DD too.


After about the third snapped drill bit I think you'll give up
on this
idea. Moreover, as another poster has mentioned, you will be
grinding a
cone and a cone can't cut. Period. Not at all.

So let's get you trained to sharpen drill bits by hand so you
can amaze
your friends, confound your enemies and have a lifetime supply
of sharp
drill bits at your beck and call.


snip excellent explanation of drill bit sharpening

When I first entered the machine trades I was given a thread
gage and
100# or so of mixed bolts to sort. I can tell metric from
English and
the various sizes and thread in each group by sight to this day
.... and
I haven't worked as a machinist for nearly 10 years.

Right after that I was given about the same weight in dulled
drill bits
to sharpen ... and one good drill bit to copy. Total
instruction
consisted of "Hold the drill bit about like this ... move it in
an arc
about like this. Make it look like the good one. There ya go.
Have at
it. Let me know when you think you've got the hang of it."

So practice, practice, practice. And let us know when you think
you've
got the hang of it. ;-)

Bill


Whoa! Talk about 'Deja Vu', just had a major flash-back to my
machinist apprenticeship at the ship yard many years ago after
reading this.

Same, same, 'sort the bolts', 'sharpen the drill bits', followed
by "This here's a properly sharpened 1/2" HSS straight cut tool
bit for that engine lathe over there. Here's a bucket of dull
ones, make 'em sharp."

Don't do much machine work these days, but I don't buy a lot of
replacement drill bits either! ;^))

Len

A cam.

"Toller" wrote in message
news
How does the machine do it; I thought it was just a simple grinding wheel,
but there must be more to it than that.

On 21 Nov 2006 06:04:25 -0800, "RayV" wrote:

A while back I had to drill out a bolt and went through several bits.
Dulling them, snapping them and as a bonus I also snapped a misnamed
easy-out. Buy new bits? Nah, they cost too much for a decent set
besides I have probably 100 drill bits. I gotta figure out a way to
sharpen them.

DAGS. Keeps coming back with buy a drill doctor. I find the thing
from Lee Valley and others that holds the bit at the correct angle to
bench grinder for $10.
http://www.leevalley.com/wood/page.a...072,43086&ap=1

The DD and the angle guide don't seem to be doing anything fancy so I
think why can't I just do it myself. Here's what I'm thinking please
tell me if you think it will work.

The Drill Doctor and the angle guide are almost certainly doing much
more than you think. Twist drills are deceptively complex.

Cut a wedge at the proper angle
Chuck the dull bit in my drill press
Clamp the wedge and a stone or fine file to the DP table
Lower the dull bit against the stone or file
Keep bit oiled and cool
Done

Nope. Take a look at the tip of a fresh drill bit- in particular, the
fact that the tip is not pointy like a pencil.

You can sharpen them freehand on a belt sander or fine grinding wheel,
but it takes a little practice, and it really helps to have someone
show you how in person. I'll try to descibe it, but I don't know how
much it will help.

Basically, there are two huge things to worry about- The first is the
tip profile. It should look like a forward slash ( / ), and not a
point. The middle of the slash should cross the center of the bit.

The second is the "wing" angle. It should be 135* on most bits.

To get the profile right, you need to start grinding near the cutting
edge (be careful not to round it off), and rotate the bit until it has
ground that entire side. You can do this several times, but you're
not rotating the bit all the way around. Once you're happy with the
first side, lift the bit off the wheel, and rotate it 180* degrees,
and repeat the process until the tip profile is centered.

It takes a fair amount of practice, but it's not too tough once you
get the hang of it.

The drill sharpeners have an indexer to get the bit in the right
position, then lock it so that it is properly aligned with the cams.
As you twist the holder, it rides on cams to raise the bit
appropriately as it nears the back of the grind. Well worth the $$$
to get one if you've got a lot of bits to sharpen, IMO.

On Tue, 21 Nov 2006 15:42:22 GMT, Frank Campbell
wrote:

In article . com, RayV
wrote:

A while back I had to drill out a bolt and went through several bits.
Dulling them, snapping them and as a bonus I also snapped a misnamed
easy-out. Buy new bits? Nah, they cost too much for a decent set
besides I have probably 100 drill bits. I gotta figure out a way to
sharpen them.

Snip
Just do as others have said and start practicing by hand, it will come
to you and and you will never look back.

I have never understood the logic of a Drill Doctor for the average
handy man, for the price of the machine a guy can buy a lot of drill
bits.

If you know how to sharpen by hand, I'm sure you're also aware of how
long a drill bit can last, if you sharpen them when they get dull.
Throwing them out because they got dull is like tossing a chisel
because it got a nick in it, or relegating a scraper to the job of
glue-spreader as soon as the burr wears off- people do it all the
time, but it's sort of an insane practice. If you actually use up one
set of drill bits, you've more than paid for the cost of a drill
doctor in replacement bits you didn't have to buy.

Len wrote:

Don't do much machine work these days, but I don't buy a lot of
replacement drill bits either! ;^))

Len


Ditto.

I didn't get to the lathe bit part until I took an intro (Machine Trades
101) class at the local Community College. On the other hand, my nearest
"hardware store" is a Production Tool ;-)

I've taught that drill sharpening technique to a lot of guys since - but
always in person. I hope that the written instruction was sufficient for
the OP (and others) to follow. It's just ridiculous to throw away a 3"
long drill bit just because the first .005" of it is dull.

I would like to add three safety tips that apply anytime a grinder is to
be used:

1) NEVER stand in line with a grinding wheel when turning it on. If it's
ever going to shatter, this is the most likely time for it.
2) NEVER mount a wheel that doesn't ring like a bell when suspended from
a nail and given a tap on the side with a small piece of metal. It
should be presumed to be cracked and just waiting for you to turn the
grinder on with it mounted. FINISH BREAKING IT to keep anyone else from
trying to mount it.
3) Eye doctors can use tiny, but powerful, magnets to tease small chunks
of metal out of your eye ... but grinding wheels aren't metal, are they?
Wear GOOD eye protection when using a bench grinder or sanding belt.
Wear goggles. Better yet, wear goggles under a face shield. Do NOT rely
on temporary side shields. DO NOT rely on your prescription lenses.
Blind is forever.

There are other safety rules for grinders (provide for lung protection,
no grinding on the side of the wheel, keep the grinding platform within
the thickness of a dime to the wheel, and so on) but these will do for a
start.

Bill

In article . com,
RayV wrote:
A while back I had to drill out a bolt and went through several bits.
Dulling them, snapping them and as a bonus I also snapped a misnamed
easy-out. Buy new bits? Nah, they cost too much for a decent set
besides I have probably 100 drill bits. I gotta figure out a way to
sharpen them.

DAGS. Keeps coming back with buy a drill doctor. I find the thing
from Lee Valley and others that holds the bit at the correct angle to
bench grinder for $10.
http://www.leevalley.com/wood/page.a...072,43086&ap=1

The DD and the angle guide don't seem to be doing anything fancy so I
think why can't I just do it myself. Here's what I'm thinking please
tell me if you think it will work.

Cut a wedge at the proper angle
Chuck the dull bit in my drill press
Clamp the wedge and a stone or fine file to the DP table
Lower the dull bit against the stone or file
Keep bit oiled and cool
Done

Unless I'm missing something doing it that way would give me the same
results as the grinder jig and probably the DD too.


The method you propose will not duplicate the geometry of a correctly
sharpened drill bit. I'm not sure I can explain it verbally, but here
goes: the surface that trails the cutting edge must be angled so that
iit provides a clearance angle for the cutting edge. If the bit was
sharpened by merely spinning it against a fixed abrasive surface, there
would be 0 deg clearance angle. Using such a bit would be equivalent
to trying to lift a shaving with a chisel while keeping the flat back
flat against the wood. IOW, without the clearance angle, the cutting
edge cannot actually contact the work.

The good news is, in larger drill sizes, it is not too difficult to
sharpen a drill bit to effectively cut wood using an ordinary bench
grinder. With more practice, you can do a passable job at sharpening a
bit to effectively cut metal as well. There are some good books out
there that will explain how, or perhaps you know someone who already
knows how. I was lucky enough to have an old machinist show me how over
30 years ago. That guy would actually take a drill bit to the grinder
and custom grind it for the type of surface he was using it on. BTW,
if you are only drilling wood with a twist bit, you can steepen the
effective cutting angle quite a bit (no pun intended) than the general
purpose metal twist bits and they will work a lot faster & cooler.

Smaller sizes are tougher to regrind by hand, depending on skill,
eyesight, steadyness of hand, etc. For me, anything smaller than 1/4"
or maybe 3/16 is a throwaway.
--
Make it as simple as possible, but no simpler.

Larry Wasserman - Baltimore Maryland -

snip

Smaller sizes are tougher to regrind by hand, depending on
skill,
eyesight, steadyness of hand, etc. For me, anything smaller
than 1/4"
or maybe 3/16 is a throwaway.
--
Make it as simple as possible, but no simpler.

Larry Wasserman - Baltimore Maryland -

Larry,

Those various sized/shaped ceramic sticks available from
Garrett-Wade, etc., work quite well for hand sharpening smaller
sized drill bits.

Hold the bit upright in a vice and run a 600/800 grit flat
ceramic stick from the back of the flute towards the cutting lip.

Use the same pressure and number of strokes on both sides.

Repeat with finer grit ceramic sticks until you've got a good
edge.

Use a 1200 grit oval shaped ceramic stick to knock the burr off
the cutting lips. The oval shape allows it to fit into the flute
of small drill bits with less chance of creating a groove than
the edge of a half-round ceramic stick (learned the hard way).

I've been able use the ceramic sticks on drill bits down to about
#60.

Len