What steel for pry bars?
Bob Engelhardt
involved). But it doesn't seem to me (by intuition ONLY) that mild
steel would be "strong" enough. It seems like it would bend too easily.
But not-bending is a matter of tensile strength, yes? And mild steel
and hard steel have the same tensile strength, right? Or, is it a
matter of yield verses ultimate strength?
Bottom line - what should I use use to make a pry bar? (It will have
very specific geometry, so store-bought is not an option.)
Thanks,
Bob
Ed Huntress
"Bob Engelhardt" <bobeng...@comcast.net> wrote in message
news:hntp7...@news3.newsguy.com...
> It doesn't have to be hard in the sense of holding an edge (no cutting
> involved). But it doesn't seem to me (by intuition ONLY) that mild steel
> would be "strong" enough. It seems like it would bend too easily.
>
> But not-bending is a matter of tensile strength, yes? And mild steel and
> hard steel have the same tensile strength, right? Or, is it a matter of
> yield verses ultimate strength?
Not-bending as in a spring is a function of stiffness. Not-bending as in
taking a permanent set is a matter of yield strength.
They have the same *stiffness* -- Young's modulus. Their yield strengths
differ greatly, and their tensile strengths do, too, in rough proportion to
their relative yield strength.
>
> Bottom line - what should I use use to make a pry bar? (It will have very
> specific geometry, so store-bought is not an option.)
It depends on how big it is and what heat treating facilities you have.
--
Ed Huntress
Tim Wescott
> It doesn't have to be hard in the sense of holding an edge (no cutting
> involved). But it doesn't seem to me (by intuition ONLY) that mild
> steel would be "strong" enough. It seems like it would bend too easily.
>
> But not-bending is a matter of tensile strength, yes? And mild steel
> and hard steel have the same tensile strength, right? Or, is it a
> matter of yield verses ultimate strength?
Tensile strength -- AFAIK this is a vague term vs. yield and ultimate
strength.
yield strength -- the 'tensile strength' at which the material begins to
permanently deform.
ultimate strength -- the 'tensile strength' at which the material
really-o truly-o breaks.
Mild and medium steels have different yield and ultimate strengths, more
or less related by elongation. Hard steels, and other brittle materials
like glass, stone, ceramic, etc., don't elongate, so their yield and
ultimate strengths are the same tensile strength.
You left out the Young's modulus, which, together with the dimensions of
the piece, determine the spring rate. _This_ is the thing that is
practically the same between mild and hard steel. It's what says "if
you stress it so much, it'll deform so much, if you stress it twice as
hard, it'll deform twice as much" -- as long as nothing's getting
permanently bent.
> Bottom line - what should I use use to make a pry bar? (It will have
> very specific geometry, so store-bought is not an option.)
Something that won't bend easily, but _will_ bend before it breaks. You
don't want it to just go "blorp" when you stress it, but you'd much
rather it bends when you're really reefing on it than to have it snap
with a ton of force behind the little bits that are still prying.
Model T Ford drive shafts make superlative pry bars, for just this reason.
As Ed alluded, it's going to be hard to make a pry bar without heat
treating facilities. I rather suspect that you want to start with
material in an annealed condition and/or bend it up using heat -- but
then you need to harden the thing, which means that you have to get the
whole mess up to a uniform temperature and quench it. And that wouldn't
be easy.
If you just need the "handle" end to have weird kinks, but the
"business" end can be normal pry bar, consider bending a normal pry bar
to shape (with generous use of a rosebud torch). You'll lose temper at
the bends, but if they're not as stressed as the ends maybe you'll get
away with it.
--
Tim Wescott
Control system and signal processing consulting
www.wescottdesign.com
Dave__67
I think a big question is, what are the dimensions?
What I see called a 'pry bar' covers a pretty big area, from thin and
wide (carpentry) to something more akin to a crowbar.
My thin carpentry ones seem to have a bit of carbon in them, given the
sparks they give off when I sharpen them.
Dave
engineman
Actually you can use Ford driveshafts made up to 1948.
They were solid bars about 1" in diameter and operated in a housing.
This housing, called a torque tube resisted the torque reaction of the
rear end housing, rather than depending on the springs.
I wish Fords were that well built these days.
I have used these driveshafts for such things as unscrewing the chuck
from a 17" lathe after it had been on for about 30 years, also prying
the tracks back on a caterpillar.
They are very difficult to bend and I've never seen one break.
I have made a lot of parts feom the steel, it can be machined with
difficulty as is and will oil harden to file hardness.
Engineman
Steve B
I will not offer any advice on how to do that. You will hear from those who
know how to make it stiff.
My comment is: Give it to me for half an hour. I'll find out if it can be
bent. I haven't met one yet that I couldn't bend. And mostly by taking
them outside their limits.
Steve
Steve B
"Bob Engelhardt" <bobeng...@comcast.net> wrote
> Bottom line - what should I use use to make a pry bar? (It will have very
> specific geometry, so store-bought is not an option.)
>
> Thanks,
> Bob
From what I know, it's not what you make it out of (well, not totally), but
how you heat and cool it afterward that makes it stiff.
Steve
Ignoramus18751
Can you bend them without using pipe extensions?
i
Snag
I can and have . And I'm not a very big guy , I only weigh around 150 - up
from 127-132 five years ago when I quit smoking . (actually 10:03 PM on the
21st will be 5 yrs) .
--
Snag
"90 FLHTCU "Strider"
'39 WLDD "PopCycle"
BS 132/SENS/DOF
Wes
>Can you bend them without using pipe extensions?
I've broke them without a pip but that is due to Far east heat cheating.
Wes
--
"Additionally as a security officer, I carry a gun to protect
government officials but my life isn't worth protecting at home
in their eyes." Dick Anthony Heller
Steve B
"Ignoramus18751" <ignoram...@NOSPAM.18751.invalid> wrote in message
news:dfmdncMuE4MDDz_W...@giganews.com...
I have, yes. When I was younger. I bent one recently straightening it by
putting a hydraulic jack on it.
Steve
Karl Townsend
Want an easy answer that should work? order 4140 from Mcmaster carr. Comes
in most any size you need. heat treating it with a torch and oil quench will
make it far stronger.
Karl
bw
I've seen one made from a truck leaf spring. Also, farm cultivator blades. I
think it's called that, it has knife like projections on the bottom. They
may be medium carbon steel shanks with hardened tips. The tips are sometimes
given a powder coat of tungsten or similar hard face.
Larry Jaques
<bobeng...@comcast.net> scrawled the following:
Oh, a likely story, Bob.
And just how are you going to teach geometry to a steel bar, hmm?
Seriousity mode: ON
I don't have any answers, but I do have more questions (some that a
person who knows steel will want answers to, too.) I have at least 5
different types of pry bars, all for different uses, all made of
different steels, and all hardened and tempered differently.
What type of prying will you be doing?
Do you want any spring to it at all? If so, how much?
How thin does it need to be at the point of highest leverage?
How big will it be? 2"? 2'? 2 meters? @ what diameter/hex?
Will you pound on it with a hammer?
What kind of abrasion will it see?
At what temp will it be used?
On what material will it be used?
(end of quick list)
I'm sure that we're both guessing that the tougher steels would get
the nod and that hardening plays an important part in the picture.
--
No matter how cynical you are, it is impossible to keep up.
--Lily Tomlin
Larry Jaques
<engin...@aol.com> scrawled the following:
>Ford model T driveshafts may be a little hard to find these days.
>Actually you can use Ford driveshafts made up to 1948.
>They were solid bars about 1" in diameter and operated in a housing.
>This housing, called a torque tube resisted the torque reaction of the
>rear end housing, rather than depending on the springs.
>I wish Fords were that well built these days.
>I have used these driveshafts for such things as unscrewing the chuck
>from a 17" lathe after it had been on for about 30 years, also prying
>the tracks back on a caterpillar.
>They are very difficult to bend and I've never seen one break.
>I have made a lot of parts feom the steel, it can be machined with
>difficulty as is and will oil harden to file hardness.
I had a section of green Chrysler torsion bar which i used as a pry
bar for years. It somehow didn't make the move with me to Oregon.
It would spring just a hair with me on the end and a about a ton of
weight leveraged at 2". I sorely miss it. It would have made a good
digging bar in my current work.
Bob Engelhardt
so that it won't "yield" as soon as mild steel would.
As to heat treating facilities, well, minimal - maximum heat capability
is propane forge. Obviously no automatic temp control.
As to what I'm making: it's for taking down tin ceilings. The ceilings
will be salvaged, so the specifics of the tool are needed to minimize
damage. The bar needs to be about 16" long, to reach over the back of a
24" tile. It needs to have a long taper, coming to a thin edge, to work
under the nails without distorting the tin. One edge needs to be 3/4"
wide to fit into a nailing space. One end will be straight & the other
have a 90 degree leg. It will be pulling out 1" long 16 ga nails, so it
won't have to be very strong - I'm thinking 1/16" thick (from trials
with a 1/16" thick putty knife).
If it wasn't for the length, I would re-shape the putty knife. Which
suggests brazing or silver soldering the knife on a longer handle - is
that doable? How about a 90 bend in it - I assume that would require
heating to bend, quenching, and tempering?
Thanks,
Bob
Ed Huntress
I'm going to bow out of discussing making this one from scratch because
there are a lot of unknowns, and I'd only be guessing. I will offer a couple
of thoughts on another approach, though.
First, what you're describing sounds quite a bit like a Red Devil pry bar
that I have -- my thinnest one, which is tapered very thin, about 1-1/2"
wide, and really strong. But it's only about 12" long and would have to be
bent near the end, which probably would leave it a lot *less* strong after
softening with a torch and a half-fast re-heat-treatment. That can be
tricky, depending on the alloy.
But if you could find one of those things you probably could drill a couple
of holes in it and screw on a longer handle. We can discuss spot-annealing
with a drill press if necessary.
I'd start with something already made if at all possible. It's not that you
need great strength, it's just that you're otherwise dealing with more
variables than it's worth.
Good luck.
--
Ed Huntress
Ignoramus18751
> OK, from what Ed & Tim said, I do want something harder than mild steel,
> so that it won't "yield" as soon as mild steel would.
>
> As to heat treating facilities, well, minimal - maximum heat capability
> is propane forge. Obviously no automatic temp control.
Do you have a firepit?
i
Steve W.
I can and do with alarming regularity! I have my own collection of bent
bars, from small flat bars up through halligan tools. Those get a bit
expensive!!!
--
Steve W.
Steve W.
I think I would try using a clamp style nail puller on a slide hammer to
remove the nails. Less damage to the tin and probably much faster. I
would probably take a set of vice grips, weld a set of tapered jaws on
the end to grip under the nail head. Then attach that to a slide hammer.
Tin is VERY, VERY easy to damage. BTDT working on a church kitchen
ceiling. Decided that decorative tin is WAY to much trouble...
--
Steve W.
Bob
Jim Wilkins
> ...
> First, what you're describing sounds quite a bit like a Red Devil pry bar
> Ed Huntress
I have several of that type and the gooseneck variant in different
sizes that I ground thin and belt-sanded smooth to loosen trim and
pull nails. Dark blue import ones that cost $3 have held up well for
this or other projects that needed a little chunk of hardened flat bar
stock.
http://www.platatac.com/www/182/files/red-devil-tool.jpg
jsw
Snag
Sounds a lot like the beekeepers little pry I have . They use it to loosen
the frames in a hive , and except for the length fits your description .
Have you looked at the "wonder bar" flat prybars ? They also fit your
description ...
Dave__67
Maybe you could modify a shingle ripper into a pry bar, since the
prying force will be pretty low.
Seems like getting the pry bar in there, then getting a fulcrum in
near it might get the nails out with a straighter pull?
Bar in, pull bar down a little, insert fulcrum (on a longish handle),
then push bar up towards the ceiling.
Dave
Larry Jaques
<csr...@NOTyahoo.com> scrawled the following:
Not a bad idea.
>Tin is VERY, VERY easy to damage. BTDT working on a church kitchen
>ceiling. Decided that decorative tin is WAY to much trouble...
It sure is when idiots install them with 2-1/2" 8-pennies. BTDT twice
(one alum/tin ceiling panel, one stainless backsplash demo which I'd
hoped to save but couldn't), damnear cursed the things out. Once I got
a tiny bit of movement, I could get the needlenose vise grips onto the
heads. I then twisted and pulled them out without any more damage.
Bob's springsteel remover wouldn't have helped, even if 1/8" thick.
Bob, how about something in the way of a wedge? Dual jaws with a
little tongue which pushes them apart? I'll bet that if you can come
up with something like that, you could sell them to metal shops.
You'll be rich! ;)
--
Adults are obsolete children. --Dr. Seuss (Theodore Geisel, 1904-1991)
--
Gunner Asch
http://www.amazon.com/b?ie=UTF8&node=553310
"First Law of Leftist Debate
The more you present a leftist with factual evidence
that is counter to his preconceived world view and the
more difficult it becomes for him to refute it without
losing face the chance of him calling you a racist, bigot,
homophobe approaches infinity.
This is despite the thread you are in having not mentioned
race or sexual preference in any way that is relevant to
the subject." Grey Ghost
Mark Rand
wrote:
Just use a slate ripper as is. shouldn't do too much damage to the tin with
16ga nails.
Mark Rand
RTFM
Larry Jaques
<gunne...@gmail.com> scrawled the following:
>On Thu, 18 Mar 2010 21:58:50 -0400, Bob Engelhardt
><bobeng...@comcast.net> wrote:
>
>>OK, from what Ed & Tim said, I do want something harder than mild steel,
>>so that it won't "yield" as soon as mild steel would.
>>
>>As to heat treating facilities, well, minimal - maximum heat capability
>>is propane forge. Obviously no automatic temp control.
>>
>>As to what I'm making: it's for taking down tin ceilings. The ceilings
>> will be salvaged, so the specifics of the tool are needed to minimize
>>damage. The bar needs to be about 16" long, to reach over the back of a
>>24" tile. It needs to have a long taper, coming to a thin edge, to work
>>under the nails without distorting the tin. One edge needs to be 3/4"
>>wide to fit into a nailing space. One end will be straight & the other
>>have a 90 degree leg. It will be pulling out 1" long 16 ga nails, so it
>>won't have to be very strong - I'm thinking 1/16" thick (from trials
>>with a 1/16" thick putty knife).
>>
>>If it wasn't for the length, I would re-shape the putty knife. Which
>>suggests brazing or silver soldering the knife on a longer handle - is
>>that doable? How about a 90 bend in it - I assume that would require
>>heating to bend, quenching, and tempering?
>>
>>Thanks,
>>Bob
>
>http://www.amazon.com/b?ie=UTF8&node=553310
Are you pointing out how many pry/crow/nail-bars there are in
existence, mon?
Bob, how about trying a shingle ripper? Throw a pair of vise grips
around the end of the flat at the handle and you have yourself a pry
bar for tin ceiling tiles. Why reinvent the wheel?
Gunner Asch
Ayup..figured he might see something that flipped his kilt up.
>
>Bob, how about trying a shingle ripper? Throw a pair of vise grips
>around the end of the flat at the handle and you have yourself a pry
>bar for tin ceiling tiles. Why reinvent the wheel?
>
>--
>Adults are obsolete children. --Dr. Seuss (Theodore Geisel, 1904-1991)
Bob Engelhardt
...
> First, what you're describing sounds quite a bit like a Red Devil pry bar
> that I have -- my thinnest one, which is tapered very thin, about 1-1/2"
Like so?
http://tinyurl.com/ycv3vdg
> I'd start with something already made if at all possible. It's not that you
> need great strength, it's just that you're otherwise dealing with more
> variables than it's worth.
I'm beginning to think that starting with something like the Red Devil
is the right way to go. But that some customization is likely. One
problem is that there are a LOT of pry bars online, but I'd really like
to put my hands on them and the best local hardware store doesn't have
that many.
Thanks,
Bob
Bob Engelhardt
...
> Dark blue import ones that cost $3 have held up well for
> this or other projects that needed a little chunk of hardened flat bar
> stock.
I'd like to find some $3 ones to play with. At the hardware store the
nice ones are $12 & others $7-8-9.
Bob
Bob Engelhardt
>> As to heat treating facilities, well, minimal - maximum heat capability
>> is propane forge. Obviously no automatic temp control.
>
> Do you have a firepit?
No, would that be better than a propane forge? Bob
Bob Engelhardt
> I think I would try using a clamp style nail puller on a slide hammer to
> remove the nails. Less damage to the tin and probably much faster. I
> would probably take a set of vice grips, weld a set of tapered jaws on
> the end to grip under the nail head. Then attach that to a slide hammer.
I'm skeptical - I think that getting under the nail head would be more
time consuming than getting behind the tin. Here's a picture of a
sharpened pry bar getting behind the tin. The arrow points to a nail head!
> Tin is VERY, VERY easy to damage. BTDT working on a church kitchen
> ceiling. Decided that decorative tin is WAY to much trouble...
It certainly is a lot of trouble! Today we discovered that some
ceilings have gotten wet and the nails rusted. The heads come off or
the tin tears before the nails pull out. !&%$#(!
We are being motivated by the high prices this stuff brings from the
yuppies. And it's volunteer labor being used <G>. There's a limit,
though, so we'll see how far it goes.
Bob
Bob Engelhardt
> ...
> Bob, how about something in the way of a wedge? Dual jaws with a
> little tongue which pushes them apart?
Maybe. But we're using bars sharpened to almost knife edge to get in
without distorting the tin too much. Two jaws might make it too thick.
I'll think about it.
I'll bet that if you can come
> up with something like that, you could sell them to metal shops.
> You'll be rich! ;)
I'll leave that to you - ambition did not follow me into retirement,
thank goodness.
Bob
Bob Engelhardt
> Maybe you could modify a shingle ripper into a pry bar, since the
> prying force will be pretty low.
I have a shingle ripper & it's much too thick & blunt. A sledge hammer
for my tack hammer job
> Seems like getting the pry bar in there, then getting a fulcrum in
> near it might get the nails out with a straighter pull?
>
> Bar in, pull bar down a little, insert fulcrum (on a longish handle),
> then push bar up towards the ceiling.
I like that. The fulcrum could be a 1/4" rod with a 90 degree leg.
Usually we can pull down to loosen, but if the bar isn't far enough in
it doesn't work.
Thanks
Bob
Ed Huntress
> Ed Huntress wrote:
> ...
>> First, what you're describing sounds quite a bit like a Red Devil pry bar
>> that I have -- my thinnest one, which is tapered very thin, about 1-1/2"
>> wide, and really strong. ...
>
> Like so?
> http://tinyurl.com/ycv3vdg
That's the one. It's served me well for around 20 years. It fits right
between a thick putty knife and my Stanley flat pry bar in thickness and
strength, and it gets a lot of use. I used it to pry off the lap siding on
one entire side of my house, and it didn't damage that 80-year-old cedar.
>
>> I'd start with something already made if at all possible. It's not that
>> you need great strength, it's just that you're otherwise dealing with
>> more variables than it's worth.
>
> I'm beginning to think that starting with something like the Red Devil is
> the right way to go. But that some customization is likely. One problem
> is that there are a LOT of pry bars online, but I'd really like to put my
> hands on them and the best local hardware store doesn't have that many.
>
> Thanks,
> Bob
Well, I hope you find one of those Red Devils or equivalent, because my
feeling is that it sounds about right for the basis for a thin pry bar as
you've described. I might try to torch it and bend it, but I think I'd just
try cutting a piece off with an abrasive wheel, spot-annealing a couple of
spots for drilling, and then drill a couple of holes for bolts through a
thicker piece of steel that would serve as a handle.
Easier said than done. <g>
--
Ed Huntress
Ignoramus28888
I have a firepit that I use, mostly, for burning cut-up pallets and
cooking hot dogs. I could heat some rather big things to red heat in
it. You need about 2 pallets for that. A comparable size propane forge
would be expensive. I have a small propane forge, with which I am very
happy.
i
Bob Engelhardt
[for a gazillion pry bars]
> http://www.amazon.com/b?ie=UTF8&node=553310
But not a one long enough & thin enough & straight.
Thanks anyhow,
Bob
BTW - this wouldn't get our nails out, but it's really cool & I want one:
http://www.amazon.com/inch-Nail-Hunter-Jack-Tools/dp/B001TE5N7G/ref=sr_1_3?ie=UTF8&s=hi&qid=1269142218&sr=1-3
Bob Engelhardt
> ... Why reinvent the wheel?
'Cause I need a wheel with a very large diameter AND narrow tread AND a
hub to fit a specific axle stub.
Bob
Bob Engelhardt
> ... Here's a picture of a
> sharpened pry bar getting behind the tin. The arrow points to a nail head!
Sorry - here it is:
http://home.comcast.net/~bobengelhardt/TinCeiling.jpg
Bob
Larry Jaques
<bobeng...@comcast.net> scrawled the following:
The tin I worked with had a _center_ nail or two. I thought that was
what you were looking to remove. Perimeters are mucho easier (but
still a major pain.)
***
Satanley makes a mini wonder bar which I use to get into small spaces.
It's made of tough spring steel, about 5" long, 1/2" wide, maybe 3/32"
thick, with a 1" long pry head. This is your best bet.
http://fwd4.me/ITT Vaughan 5-1/4"?
***
I grind the curved end of my HF multipurpose pry bars thin on the belt
sandah for trim and tin, too. http://fwd4.me/ITO
Then again, tin is easily beat back into shape on the edges. Stock up
on repousse hammers and make wooden dies for the edge shapes with a
dremel and tubafore if necessary.
I'd also use a scribe to remove the paint from that joint so you can
see the edge you're after a bit more clearly.
--
If we attend continually and promptly to the little that we can do, we
shall ere long be surprised to find how little remains that we cannot do.
-- Samuel Butler
Bob Engelhardt
> The tin I worked with had a _center_ nail or two. I thought that was
> what you were looking to remove. Perimeters are mucho easier (but
Yes and no. We remove the nails on one side, from the front, as shown.
Then with that side loose, we go behind the tin to remove the nails on
the other side from behind. Reaching behind the 24" wide panel gives us
the need for a long bar.
> Then again, tin is easily beat back into shape on the edges. Stock up
> on repousse hammers and make wooden dies for the edge shapes with a
> dremel and tubafore if necessary.
Indeed, but we'd like to avoid as much of that as possible.
> I'd also use a scribe to remove the paint from that joint so you can
> see the edge you're after a bit more clearly.
Good point.
Thanks,
Bob
Larry Jaques
<bobeng...@comcast.net> scrawled the following:
>Bob Engelhardt wrote:
Crikey! Of _course_ it's painted. (what a shame!)
Steve W.
> Steve W. wrote:
>> I think I would try using a clamp style nail puller on a slide hammer to
>> remove the nails. Less damage to the tin and probably much faster. I
>> would probably take a set of vice grips, weld a set of tapered jaws on
>> the end to grip under the nail head. Then attach that to a slide hammer.
>
> I'm skeptical - I think that getting under the nail head would be more
> time consuming than getting behind the tin. Here's a picture of a
> sharpened pry bar getting behind the tin. The arrow points to a nail head!
With a sharp set of points it should be easier to get under the heads
than tearing the tin. Even with the paint on there. Have you tried a
GOOD cats paw?
>
>> Tin is VERY, VERY easy to damage. BTDT working on a church kitchen
>> ceiling. Decided that decorative tin is WAY to much trouble...
>
> It certainly is a lot of trouble! Today we discovered that some
> ceilings have gotten wet and the nails rusted. The heads come off or
> the tin tears before the nails pull out. !&%$#(!
In that case I would probably try a flush cutting tool and just cut the
heads off.
This style will get in under the head
http://www.shorinternational.com/images/ImagesP/plr784.gif
>
> We are being motivated by the high prices this stuff brings from the
> yuppies. And it's volunteer labor being used <G>. There's a limit,
> though, so we'll see how far it goes.
>
> Bob
--
Steve W.
Bob Engelhardt
> With a sharp set of points it should be easier to get under the heads
> than tearing the tin. Even with the paint on there. Have you tried a
> GOOD cats paw?
All the cat's paws I have access to are much too crude/blunt/thick. But
your post's inspired me to try making one.
> In that case I would probably try a flush cutting tool and just cut the
> heads off.
> This style will get in under the head
> http://www.shorinternational.com/images/ImagesP/plr784.gif
That's a nice one - the site has a bunch of nice cutters:
http://www.shorinternational.com/pliersend.htm
The 2nd one down, the "Oblique Flush Cut Nippers" ($168.00) looks very
well made <G>.
Bob
Michael A. Terrell
How about a hollow punch, to cut the metal around the nail head?
--
Lead free solder is Belgium's version of 'Hold my beer and watch this!'
Tim Wescott
> Bob Engelhardt wrote:
>> OK, from what Ed & Tim said, I do want something harder than mild steel,
>> so that it won't "yield" as soon as mild steel would.
>>
>> is propane forge. Obviously no automatic temp control.
>>
>> will be salvaged, so the specifics of the tool are needed to minimize
>> damage. The bar needs to be about 16" long, to reach over the back of a
>> 24" tile. It needs to have a long taper, coming to a thin edge, to work
>> under the nails without distorting the tin. One edge needs to be 3/4"
>> wide to fit into a nailing space. One end will be straight & the other
>> have a 90 degree leg. It will be pulling out 1" long 16 ga nails, so it
>> won't have to be very strong - I'm thinking 1/16" thick (from trials
>> with a 1/16" thick putty knife).
>>
>> If it wasn't for the length, I would re-shape the putty knife. Which
>> suggests brazing or silver soldering the knife on a longer handle - is
>> that doable? How about a 90 bend in it - I assume that would require
>> heating to bend, quenching, and tempering?
>>
>> Thanks,
>> Bob
>>
>
> remove the nails. Less damage to the tin and probably much faster. I
> would probably take a set of vice grips, weld a set of tapered jaws on
> the end to grip under the nail head. Then attach that to a slide hammer.
>
> ceiling. Decided that decorative tin is WAY to much trouble...
>
Just grab the thing firmly then chin yourself up on the puller.
Grabbing it, obviously, is still an issue.
--
Tim Wescott
Control system and signal processing consulting
www.wescottdesign.com
Steve W.
> Steve W. wrote:
>> With a sharp set of points it should be easier to get under the heads
>> than tearing the tin. Even with the paint on there. Have you tried a
>> GOOD cats paw?
>
> All the cat's paws I have access to are much too crude/blunt/thick. But
> your post's inspired me to try making one.
I'll tell you the best one I have is an import from Japan. It is high
quality steel and the working end is shaped well and VERY sharp. The
jaws will lift the head of a sewing pin driven into wood!
>
>> In that case I would probably try a flush cutting tool and just cut the
>> heads off.
>> This style will get in under the head
>> http://www.shorinternational.com/images/ImagesP/plr784.gif
>
> That's a nice one - the site has a bunch of nice cutters:
> http://www.shorinternational.com/pliersend.htm
> The 2nd one down, the "Oblique Flush Cut Nippers" ($168.00) looks very
> well made <G>.
>
> Bob
I have seen the same ones in other places. They may need a bit of work
on a belt sander to shape them some.
--
Steve W.
Jim Wilkins
> Bob Engelhardt wrote:
>...
> > The 2nd one down, the "Oblique Flush Cut Nippers" ($168.00) looks very
> > well made <G>.
If you can afford to sacrifice them dikes like this work very well to
grab and lever out small nails:
http://www.adafruit.com/images/large/toolboxcutter_LRG.jpg
Pad under the hinge pin with cardboard or such to spread the pressure.
Just don't expect them to cut component leads afterwards.
I passed the word around Assembly that I collected broken cutters and
pliers to recycle into special tools.
jsw
Martin H. Eastburn
pull the nail out.
Martin
Bob Engelhardt
> Steve W. wrote:
>
> All the cat's paws I have access to are much too crude/blunt/thick. But
> your post's inspired me to try making one.
OK - I did make one. I took an old 1/4" wood chisel & ground away the
part that wasn't a cat's paw. Very sharp edge.
No good. The problem is that the tin is only 30 ga (.012) and when
nailed up, the nail dimples the tin very slightly. The nail is actually
countersunk a bit - just enough to make getting under the nail very
difficult. Damaging the tin more than desirable.
Getting a pry bar behind the tin is really the way to go.
Thanks,
Bob
Bob Engelhardt
> ... dikes like this work very well to grab and lever out small nails:
> http://www.adafruit.com/images/large/toolboxcutter_LRG.jpg
...
I took an old pair if linesman's pliers and cut/ground them down to be
end nippers. Well, end grabbers. Even though I made the ends sharp,
they would not get under the head. Because of the slight countersinking
I mentioned above.
Bob
Bob Engelhardt
>>> ... Today we discovered that some
>>> ceilings have gotten wet and the nails rusted. The heads come off or
>>> the tin tears before the nails pull out. !&%$#(!
Martin H. Eastburn wrote:
> I'd grind off the nail head - take the tin off and with a Vice-grip
> plier pull the nail out.
Ah - that's what I thought, too. I tried it today - too much collateral
damage, as they say, to the tin. Again the problem is with the nails
being slightly countersunk. That and working over your head while
standing on a step ladder.
It keep coming back to prying off from behind. As many alternatives
that I try, it's still the best: fastest,easiest, safest.
Thanks,
Bob
Larry Jaques
<bobeng...@comcast.net> scrawled the following:
>>> Bob Engelhardt wrote:
>>>> ... Today we discovered that some
>>>> ceilings have gotten wet and the nails rusted. The heads come off or
>>>> the tin tears before the nails pull out. !&%$#(!
>...
>
>Martin H. Eastburn wrote:
> > I'd grind off the nail head - take the tin off and with a Vice-grip
> > plier pull the nail out.
>
>Ah - that's what I thought, too. I tried it today - too much collateral
>damage, as they say, to the tin. Again the problem is with the nails
>being slightly countersunk. That and working over your head while
>standing on a step ladder.
Were you using a small, sintered carbide ball? (and 3 layers of eye
protection?)
>It keep coming back to prying off from behind. As many alternatives
>that I try, it's still the best: fastest,easiest, safest.
I hear that. Didja try one of those little Satanley or Vaughan
mini-bars yet? Alternatively, make your own tiny cat's paw out of
1/4" rod. Flatten, curve, notch, grind, and harden/temper. I wonder
if a standard 8" timber spike/nail might work. They're pretty tough.
Bob Engelhardt
[re - grinding head off nails]
> Were you using a small, sintered carbide ball?
No, but that's a good idea. I was using a cylindrical carbide burr. I
don't have a carbide ball, but I do have an HSS one that I can use for a
trial.
> (and 3 layers of eye protection?)
Indeed - those burrs send out millions of TINY, needle-like, slivers!
Thanks,
Bob
sn...@triped.net
I wonder if a really powerful magnet might be utilized to get the
nails out far enough to get a good grip?
Snarl
Tim Wescott
Place the jaws of the pliers so that they are just over, but not
engaging the nail head. Push _up_, _hard_. See if that gives you
clearance to grab the head.
Bob Engelhardt
> Place the jaws of the pliers so that they are just over, but not
> engaging the nail head. Push _up_, _hard_. See if that gives you
> clearance to grab the head.
No way. But, what DID work was to hold the pliers there and tap _up_
with a hammer. A mallet, actually, with a head big enough to hit both
handles at once.
The majority of nails can be pried from behind, but the rusty ones can't
and this should "work a treat" on them.
Thanks,
Bob
Dave__67
How about a nice sticky gooey acid that will eat the nail and not the
ceiling tile?
Just remember, do not check acid progress with remaining eye...
Dave
Larry Jaques
<bobeng...@comcast.net> scrawled the following:
>Larry Jaques wrote:
>[re - grinding head off nails]
>
>> Were you using a small, sintered carbide ball?
>
>No, but that's a good idea. I was using a cylindrical carbide burr. I
>don't have a carbide ball, but I do have an HSS one that I can use for a
>trial.
And how much harder do you expect the HSS ball to be tahn the head of
a hardened nail, hmmm? There goes a good burr. And when a burr goes,
it sometimes loses pieces. They're dangerous little guys.
Stone burrs can work, too, if someone donates several dozen. They
grind themselves down really fast on metal and also shoot pieces when
they go.
(std disclaimer, googledit) http://www.duragrit.com/ The shape and
type I'm referring to is like these: numbers 10/13/14/18 would work.
Aim for the center of the nail head and the head pops off when you cut
through its thickness, sweet and smooth.
>> (and 3 layers of eye protection?)
>
>Indeed - those burrs send out millions of TINY, needle-like, slivers!
Yeah, nasty stuff which bounces off your cheak, into your glasses and
then right into your eye.
P.S: Don't forget muffs or plugs. It's noisy as hell.
Larry Jaques
<bobeng...@comcast.net> scrawled the following:
>Tim Wescott wrote:
Yeah, find a piece of tubing or pipe which is just slightly larger in
diameter than the nail head and create your own puller space.
John Martin
it. A long V, with sides ground from very acute at the open end to
almost vertical at the base of the V. Use it under the tin, and with
a pushing action only - no prying. If you can get it in to the bottom
of the notch, the nail will have broken loose a bit - and you can then
push a thin prybar under the knife and use that to pry the knife, tin
and nail out. Or use a second V notch knife to lift the nail even
further before you try a prybar. This will avoid what in my
experience is the most common problem - tearing the tin at the rim of
the nail head before you can get anything under it. And it won't hurt
the show surface of the tin at all.
So a putty knife wouldn't be long enough working under the tin? Check
McMaster or other sources and you'll find many different similar
knives, spatulas and scrapers, but much longer and stronger.
Printer's ink knives come to mind.
Just my thoughts, though.
John Martin
dan
rec.crafts.metalworking mine and will die if we don't mount a rescue
by Tue, 23 Mar 2010 20:39:48 -0400:
>It keep coming back to prying off from behind. As many alternatives
>that I try, it's still the best: fastest,easiest, safest.
Bob, how much clearance is there on the other side from where you are
working? If it is several inches, you might have luck with a long
flat blade with a groove down the middle of it( just one nail shank
wide). The blade will need to be thin and edged at the front and get
thicker as it goes back. The increasing thickness lifts the nail(and
tin) away from the ceiling.
--
Dan H.
northshore MA.
Wes
>I had a section of green Chrysler torsion bar which i used as a pry
>bar for years. It somehow didn't make the move with me to Oregon.
>
>It would spring just a hair with me on the end and a about a ton of
>weight leveraged at 2". I sorely miss it. It would have made a good
>digging bar in my current work.
Having had a few Chrysler products when they used torsion bars, I have no doubt that chunk
of steel made a fantastic pry bar.
Wes
Wes
Bob Engelhardt
Both, kinda - tin plated steel. Like "tin" cans. Bob