On Mon, 13 Oct 2008 23:42:20 +0000, Christopher Tidy
wrote:

Hi folks,

I am looking for a flat screwdriver with an exceptionally thin blade,
for use on clock mechanisms. The blade needs to be at least 3/16" long,
but no more than 25/1000" thick. Does anyone know of a source for such a
screwdriver? UK sources are preferred, if anyone knows of them.

I know I can try grinding my own, but I'm not convinced I can do it neatly.

Follow-ups set to rec.crafts.metalworking.

Many thanks,

Chris Tidy
When you say 3/16 long I assume that you mean 3/16 a wide tip.
Take a 3/16 dia screwdriver. Slide an appropriate drill stop onto
blade. With your off hand grinder "off", Put the blade to the wheel
with the tip near tangential and the shank resting againstthe tool
rest. Tighten the drill stopjust resting under the tool rest.
Run the grinder and grind each side of the tip until .025 or less
achieved. Now grind or stone the tip face until .025 or to fit screw.

All takes less time than writing this or reading
rec.crafts.metalworking.

Richard

Christopher Tidy writes:

I can't quite get my head around what you're doing here. How can you
have the screwdriver tip tangential to the grinding wheel, and the
shank resting on the toolrest? Surely the two positions are 90 degrees
apart?

The toolrests on my grinder are adjustable. I'm not sure I've ever
seen one that wasn't. Even if yours isn't, for an application like
this you could be resting it on the far edge of the rest.

Richard Edwards wrote:
On Mon, 13 Oct 2008 23:42:20 +0000, Christopher Tidy
wrote:


Hi folks,

I am looking for a flat screwdriver with an exceptionally thin blade,
for use on clock mechanisms. The blade needs to be at least 3/16" long,
but no more than 25/1000" thick. Does anyone know of a source for such a
screwdriver? UK sources are preferred, if anyone knows of them.

I know I can try grinding my own, but I'm not convinced I can do it neatly.

Follow-ups set to rec.crafts.metalworking.

Many thanks,

Chris Tidy

When you say 3/16 long I assume that you mean 3/16 a wide tip.
Take a 3/16 dia screwdriver. Slide an appropriate drill stop onto
blade. With your off hand grinder "off", Put the blade to the wheel
with the tip near tangential and the shank resting againstthe tool
rest. Tighten the drill stopjust resting under the tool rest.
Run the grinder and grind each side of the tip until .025 or less
achieved. Now grind or stone the tip face until .025 or to fit screw.

I can't quite get my head around what you're doing here. How can you
have the screwdriver tip tangential to the grinding wheel, and the shank
resting on the toolrest? Surely the two positions are 90 degrees apart?

Best wishes,

Chris

On 2008-10-15, Christopher Tidy wrote:
Richard Edwards wrote:

[ ... ]

When you say 3/16 long I assume that you mean 3/16 a wide tip.
Take a 3/16 dia screwdriver. Slide an appropriate drill stop onto
blade. With your off hand grinder "off", Put the blade to the wheel
with the tip near tangential and the shank resting againstthe tool
rest. Tighten the drill stopjust resting under the tool rest.
Run the grinder and grind each side of the tip until .025 or less
achieved. Now grind or stone the tip face until .025 or to fit screw.

I can't quite get my head around what you're doing here. How can you
have the screwdriver tip tangential to the grinding wheel, and the shank
resting on the toolrest? Surely the two positions are 90 degrees apart?

Yes -- about. Maybe down to 60 degrees or so. The shank is
resting against the lip of the toolrest as he described it, with a
slid-on collar resting against the toolrest to keep the extension of the
screwdriver blade long enough.

Enjoy,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

DoN. Nichols wrote:
On 2008-10-15, Christopher Tidy wrote:

Richard Edwards wrote:


[ ... ]


When you say 3/16 long I assume that you mean 3/16 a wide tip.
Take a 3/16 dia screwdriver. Slide an appropriate drill stop onto
blade. With your off hand grinder "off", Put the blade to the wheel
with the tip near tangential and the shank resting againstthe tool
rest. Tighten the drill stop just resting under the tool rest.
Run the grinder and grind each side of the tip until .025 or less
achieved. Now grind or stone the tip face until .025 or to fit screw.

I can't quite get my head around what you're doing here. How can you
have the screwdriver tip tangential to the grinding wheel, and the shank
resting on the toolrest? Surely the two positions are 90 degrees apart?


Yes -- about. Maybe down to 60 degrees or so. The shank is
resting against the lip of the toolrest as he described it, with a
slid-on collar resting against the toolrest to keep the extension of the
screwdriver blade long enough.

Right. Got it. Richard said "drill stop just resting under the tool
rest". It was the word "under" which confused me.

I don't have any drill stops, though. Are they a good investment? I use
a depth scale on my bench drill, which works some of the time, but it is
possible to overshoot when using it.

Best wishes,

Chris

On 2008-10-16, Christopher Tidy wrote:
DoN. Nichols wrote:

[ ... ]

Yes -- about. Maybe down to 60 degrees or so. The shank is
resting against the lip of the toolrest as he described it, with a
slid-on collar resting against the toolrest to keep the extension of the
screwdriver blade long enough.

Right. Got it. Richard said "drill stop just resting under the tool
rest". It was the word "under" which confused me.

Well ... it could be under or above -- just as long as it
defines the extension of the drill rod while you are grinding it.

I don't have any drill stops, though. Are they a good investment?

It depends on what you are doing. If you are doing a lot of
drilling with a hand-held drill through things where there is something
behind it which could be damaged, then a drill stop is important.

But -- you can *make* your own you know. Drill through the end
of some round stock the size of the bit, turn the end smooth, drill into
the side and tap for a setscrew to hold it onto the drill bit. No need
to buy them in a bunch of sizes which you may never use. (I'm assuming
that you have a lathe -- though you could do all of this with a drill
press and a file if you had to.

I use
a depth scale on my bench drill, which works some of the time, but it is
possible to overshoot when using it.

Isn't there a quill stop? for the ones which have a scale
around the feed, there is usually a wing-topped setscrew to allow you to
clamp it to the the feed shank and limit the travel of the quill.

Better is when there is a vertical threaded shaft connected to
the quill with an adjustable depth stop there.

Of course -- for certain things, there are much better tools
available. For countersinks, there is the Micro-Stop, which can be
adjusted for depth in steps of 0.001". These are commonly used in
aircraft production -- for riveted joints with flat-head rivets, but can
also be used with countersunk screws, or even to put a very shallow bevel
on a drilled hole. The micro-stop has a thrust bearing to firmly stop
the drill or countersink and a cage which contacts the work surface.
One of these is nice to have -- just in general. Find used ones on
eBay, don't play new price games with them. :-)

Good Luck,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

DoN. Nichols wrote:

I don't have any drill stops, though. Are they a good investment?


It depends on what you are doing. If you are doing a lot of
drilling with a hand-held drill through things where there is something
behind it which could be damaged, then a drill stop is important.

But -- you can *make* your own you know. Drill through the end
of some round stock the size of the bit, turn the end smooth, drill into
the side and tap for a setscrew to hold it onto the drill bit. No need
to buy them in a bunch of sizes which you may never use. (I'm assuming
that you have a lathe -- though you could do all of this with a drill
press and a file if you had to.

I have trouble getting my father's lathe to drill a piece of work
centrally. The tailstock can be moved from side to side using set
screws, but not up and down. It seems to be out in the vertical
direction. I think the problem is that there's a cap screw under the
tailstock which is unoriginal and has a head which protrudes slightly,
causing the tailstock to sit at the wrong level. But as it's my father's
lathe I have been reluctant to try fixing it.
I use
a depth scale on my bench drill, which works some of the time, but it is
possible to overshoot when using it.


Isn't there a quill stop? for the ones which have a scale
around the feed, there is usually a wing-topped setscrew to allow you to
clamp it to the the feed shank and limit the travel of the quill.

No there isn't. There's just a scale. It's a cheap drill press.

Better is when there is a vertical threaded shaft connected to
the quill with an adjustable depth stop there.

Of course -- for certain things, there are much better tools
available. For countersinks, there is the Micro-Stop, which can be
adjusted for depth in steps of 0.001". These are commonly used in
aircraft production -- for riveted joints with flat-head rivets, but can
also be used with countersunk screws, or even to put a very shallow bevel
on a drilled hole. The micro-stop has a thrust bearing to firmly stop
the drill or countersink and a cage which contacts the work surface.
One of these is nice to have -- just in general. Find used ones on
eBay, don't play new price games with them. :-)

Sounds like a neat tool.

Best wishes,

Chris

On 2008-10-18, Christopher Tidy wrote:
DoN. Nichols wrote:

I don't have any drill stops, though. Are they a good investment?


It depends on what you are doing. If you are doing a lot of
drilling with a hand-held drill through things where there is something
behind it which could be damaged, then a drill stop is important.

But -- you can *make* your own you know. Drill through the end
of some round stock the size of the bit, turn the end smooth, drill into

[ ... ]

I have trouble getting my father's lathe to drill a piece of work
centrally. The tailstock can be moved from side to side using set
screws, but not up and down. It seems to be out in the vertical
direction. I think the problem is that there's a cap screw under the
tailstock which is unoriginal and has a head which protrudes slightly,
causing the tailstock to sit at the wrong level. But as it's my father's
lathe I have been reluctant to try fixing it.

Hmm ... I wonder whether that was an attempt to adjust for a
tailstock which was too low? Ask him about it, including whether you,
or the two of you together, can try to fix that problem. Why not take
the screw out, determine the threads, get a spare of the same size, and
turn off enough head length to prevent the contact. (This way, you can
go back to the original screw if you need to.)

And if it then too *low* -- the proper fix is shim stock of the
appropriate thickness between the base and the top casting which moves
sideways. Same thickness shim stock both sides of the screw so the
barrel remains level.

a depth scale on my bench drill, which works some of the time, but it is
possible to overshoot when using it.


Isn't there a quill stop? for the ones which have a scale
around the feed, there is usually a wing-topped setscrew to allow you to
clamp it to the the feed shank and limit the travel of the quill.

No there isn't. There's just a scale. It's a cheap drill press.

Hmm ... does the scale (or the pointer) rotate as you feed the
quill? Mine was a cheap drill press back in about 1976 or so when I got
it new. Taiwan made, floor standing, 16 speeds. Check for a hole in
the part which contains the pointer or the scale. If you find one,
check whether there is a setscrew in there -- perhaps installed to keep
the scale constant. Remove this, replace it with a longer screw, and
you could have an adjustable stop in that rotating collar.

As for drill stops -- you can make them simply by taking tubing
of a reasonable diameter, turning to the right length, and then slipping
it on over the drill bit until it touches the chuck jaws. You may have
to hold it in place -- or stuff it with cotton or blu-tack to keep it
from slipping down onto the workpiece.

Enjoy,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

DoN. Nichols wrote:

Hmm ... I wonder whether that was an attempt to adjust for a
tailstock which was too low? Ask him about it, including whether you,
or the two of you together, can try to fix that problem. Why not take
the screw out, determine the threads, get a spare of the same size, and
turn off enough head length to prevent the contact. (This way, you can
go back to the original screw if you need to.)

And if it then too *low* -- the proper fix is shim stock of the
appropriate thickness between the base and the top casting which moves
sideways. Same thickness shim stock both sides of the screw so the
barrel remains level.

I had a look at it. My father is happy for me to attempt to fix it, as
long as I don't do anything irreversible. It looks like the head of the
cap screw protrudes by about 1/32", whereas it should be flush or below
flush. I think the screw is either 1/4" or 5/16" BSW, which will not be
an easy size to get. First I think I will remove the screw and see if
there is anything underneath it. It is odd as I thought that the height
of cap screw heads were mostly standard.

a depth scale on my bench drill, which works some of the time, but it is
possible to overshoot when using it.


Isn't there a quill stop? for the ones which have a scale
around the feed, there is usually a wing-topped setscrew to allow you to
clamp it to the the feed shank and limit the travel of the quill.

No there isn't. There's just a scale. It's a cheap drill press.


Hmm ... does the scale (or the pointer) rotate as you feed the
quill? Mine was a cheap drill press back in about 1976 or so when I got
it new. Taiwan made, floor standing, 16 speeds. Check for a hole in
the part which contains the pointer or the scale. If you find one,
check whether there is a setscrew in there -- perhaps installed to keep
the scale constant. Remove this, replace it with a longer screw, and
you could have an adjustable stop in that rotating collar.

No, nothing rotates. The scale is a sticker and the pointer is a piece
of steel plate crimped onto a length of threaded rod. It's not a great
drill press. I am hoping to get another soon. I thought about getting an
Arboga drill a while back, but then decided not in case I got a mill,
because that would make it redundant.

As for drill stops -- you can make them simply by taking tubing
of a reasonable diameter, turning to the right length, and then slipping
it on over the drill bit until it touches the chuck jaws. You may have
to hold it in place -- or stuff it with cotton or blu-tack to keep it
from slipping down onto the workpiece.

I had another idea. The problem with the scale on the drill press at the
moment is that you can't look at the scale and the piece of work at the
same time. So I thought for now I might just wrap a piece of coloured
tape around the drill. It would at least be directly in my field of
view, even if it isn't a hard stop.

Best wishes,

Chris

On 2008-10-19, Christopher Tidy wrote:
DoN. Nichols wrote:

Hmm ... I wonder whether that was an attempt to adjust for a
tailstock which was too low? Ask him about it, including whether you,
or the two of you together, can try to fix that problem. Why not take
the screw out, determine the threads, get a spare of the same size, and
turn off enough head length to prevent the contact. (This way, you can
go back to the original screw if you need to.)

And if it then too *low* -- the proper fix is shim stock of the
appropriate thickness between the base and the top casting which moves
sideways. Same thickness shim stock both sides of the screw so the
barrel remains level.

I had a look at it. My father is happy for me to attempt to fix it, as
long as I don't do anything irreversible. It looks like the head of the
cap screw protrudes by about 1/32", whereas it should be flush or below
flush. I think the screw is either 1/4" or 5/16" BSW, which will not be
an easy size to get. First I think I will remove the screw and see if
there is anything underneath it. It is odd as I thought that the height
of cap screw heads were mostly standard.

Is it possible that the original screw was a slotted head screw
instead -- and someone replaced it with the BSW? Or perhaps the threads
in the hole had been stripped out and it was drilled larger and tapped
for the next size up -- which would of course have a larger head.

[ ... ]

Isn't there a quill stop? for the ones which have a scale
around the feed, there is usually a wing-topped setscrew to allow you to
clamp it to the the feed shank and limit the travel of the quill.

No there isn't. There's just a scale. It's a cheap drill press.


Hmm ... does the scale (or the pointer) rotate as you feed the
quill? Mine was a cheap drill press back in about 1976 or so when I got
it new. Taiwan made, floor standing, 16 speeds. Check for a hole in
the part which contains the pointer or the scale. If you find one,
check whether there is a setscrew in there -- perhaps installed to keep
the scale constant. Remove this, replace it with a longer screw, and
you could have an adjustable stop in that rotating collar.

No, nothing rotates. The scale is a sticker and the pointer is a piece
of steel plate crimped onto a length of threaded rod.

Oh -- that design. The threaded rod is attached to the quill
and moves downward with it? Does it move through a hole or a slot in a
projection from the main casting? If so -- then a depth stop is as
simple as placing a pair of nuts onto the threaded rod, spinning them
down so they touch the projection when the drill bit is at the right
depth, and tightening the two nuts together so they don't vibrate and
change their setting.

And that pointer was probably originally a bent piece of steel
producing two holes for the rod to pass through and capturing between
them a knurled OD nut to allow the pointer to be moved up and down as
needed. There should be a spring to keep the knurled OD nut from
rotating except when you *want* to rotate it -- and perhaps even an
arrangement so when you press a tab the threads disengage to allow
quick motion of the stop.

This is the old way to serve as a depth stop -- present on many
quality drill presses. I suspect that the head casting is split at the
bottom and there is a bent lever which will tighten it around the quill
so you can lock the quill in an extended position as well.

It's not a great
drill press. I am hoping to get another soon.

It may be better than you think -- just missing some parts. Can
you post a close-up of the head part -- especially the threaded rod?
(You can either put them on your own web space, or submit them to the
dropbox (http://www.metalworking.com) and then post the resulting URL
here for us to follow and look at it.

I thought about getting an
Arboga drill a while back, but then decided not in case I got a mill,
because that would make it redundant.

As for drill stops -- you can make them simply by taking tubing
of a reasonable diameter, turning to the right length, and then slipping
it on over the drill bit until it touches the chuck jaws. You may have
to hold it in place -- or stuff it with cotton or blu-tack to keep it
from slipping down onto the workpiece.

I had another idea. The problem with the scale on the drill press at the
moment is that you can't look at the scale and the piece of work at the
same time. So I thought for now I might just wrap a piece of coloured
tape around the drill. It would at least be directly in my field of
view, even if it isn't a hard stop.

Yes -- that can work. I've done similar things around a boring
bar when boring a hole with a bottom instead of a through hole -- and
when threading the ID of a hole as well.

Enjoy,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

DoN. Nichols wrote:

I apologise for taking a while to get back to you.

I had a look at it. My father is happy for me to attempt to fix it, as
long as I don't do anything irreversible. It looks like the head of the
cap screw protrudes by about 1/32", whereas it should be flush or below
flush. I think the screw is either 1/4" or 5/16" BSW, which will not be
an easy size to get. First I think I will remove the screw and see if
there is anything underneath it. It is odd as I thought that the height
of cap screw heads were mostly standard.


Is it possible that the original screw was a slotted head screw
instead -- and someone replaced it with the BSW? Or perhaps the threads
in the hole had been stripped out and it was drilled larger and tapped
for the next size up -- which would of course have a larger head.

I think there are two possibilities. The first it that the head of the
screw is of the wrong dimensions. The second is that there's something
stuck under the head, perhaps a washer or even some swarf. I don't think
that the hole has been damaged and re-tapped. There is no evidence the
the screw is larger than would be expected, and to be honest it's very
difficult to see how it alone would have got damaged, given its
location. I am pretty sure that the screw would break before stripping
the thread, given the length of the thread. With a 5/16" screw this
would take a lot of force, and there is no sign of damage anywhere on
the lathe.

I suppose it's conceivable that someone has replaced the BSW screw with
a UNC screw with different head dimensions, as the two standards
sometimes have matching diameters and pitches, even though the thread
angles are different.

I don't think I will know until I get chance to take it out. If I have a
chance this weekend, I will.

Isn't there a quill stop? for the ones which have a scale
around the feed, there is usually a wing-topped setscrew to allow you to
clamp it to the the feed shank and limit the travel of the quill.

No there isn't. There's just a scale. It's a cheap drill press.


Hmm ... does the scale (or the pointer) rotate as you feed the
quill? Mine was a cheap drill press back in about 1976 or so when I got
it new. Taiwan made, floor standing, 16 speeds. Check for a hole in
the part which contains the pointer or the scale. If you find one,
check whether there is a setscrew in there -- perhaps installed to keep
the scale constant. Remove this, replace it with a longer screw, and
you could have an adjustable stop in that rotating collar.

No, nothing rotates. The scale is a sticker and the pointer is a piece
of steel plate crimped onto a length of threaded rod.


Oh -- that design. The threaded rod is attached to the quill
and moves downward with it? Does it move through a hole or a slot in a
projection from the main casting? If so -- then a depth stop is as
simple as placing a pair of nuts onto the threaded rod, spinning them
down so they touch the projection when the drill bit is at the right
depth, and tightening the two nuts together so they don't vibrate and
change their setting.

I looked and there are a pair of half nuts (as distinct from split nuts)
at the top. I'd never noticed them before. Thanks for making the
suggestion. That's a useful discovery.

And that pointer was probably originally a bent piece of steel
producing two holes for the rod to pass through and capturing between
them a knurled OD nut to allow the pointer to be moved up and down as
needed. There should be a spring to keep the knurled OD nut from
rotating except when you *want* to rotate it -- and perhaps even an
arrangement so when you press a tab the threads disengage to allow
quick motion of the stop.

No, there's no space for a nut within the pointer. It is just crimped
onto a reduced diameter section of the rod at the top.

This is the old way to serve as a depth stop -- present on many
quality drill presses. I suspect that the head casting is split at the
bottom and there is a bent lever which will tighten it around the quill
so you can lock the quill in an extended position as well.

No, it's definitely a one-piece head casting. There isn't even a wing
bolt for locking the quill. It's a very cheap drill press, but to be
fair it performs adequately for many jobs. It is not useless.

It's not a great
drill press. I am hoping to get another soon.


It may be better than you think -- just missing some parts. Can
you post a close-up of the head part -- especially the threaded rod?
(You can either put them on your own web space, or submit them to the
dropbox (http://www.metalworking.com) and then post the resulting URL
here for us to follow and look at it.

Hopefully I've explained the features of the drill press, but if you'd
like a picture I'm more than happy to post one.

I thought about getting an
Arboga drill a while back, but then decided not in case I got a mill,
because that would make it redundant.


As for drill stops -- you can make them simply by taking tubing
of a reasonable diameter, turning to the right length, and then slipping
it on over the drill bit until it touches the chuck jaws. You may have
to hold it in place -- or stuff it with cotton or blu-tack to keep it
from slipping down onto the workpiece.

I had another idea. The problem with the scale on the drill press at the
moment is that you can't look at the scale and the piece of work at the
same time. So I thought for now I might just wrap a piece of coloured
tape around the drill. It would at least be directly in my field of
view, even if it isn't a hard stop.


Yes -- that can work. I've done similar things around a boring
bar when boring a hole with a bottom instead of a through hole -- and
when threading the ID of a hole as well.

Now I've discovered the system for limiting the travel of the quill,
I'll use it. It's going to be superior to either tape or drill stops.

Many thanks,

Chris