I'm still working on putting together a home smithy. I'm wondering about
hot-cut tools, both hardie and top. Specifically, I'm curious if I can
just take an old log-splitting wedge and weld a hardie shaft onto it
and use it as a hot chisel - i.e. a hardie tool. I'm also wondering
if I could use a common hatchet as a hot cut tool.
Grant Erwin
Kirkland, Washington
Both the wedge and the hatchet have to be soft enough to file to
resharpen and soft enought that the don't chip much from impact. I
think they are both too soft for what you want. Anyway, if they were
hardened, and if they were plain carbon steel, which the probably are,
then using them as hot cutters will temper them to be too soft anyway.
If you invest in a new piece of tool steel and make proper cutters,
you will be using them many years from now with no problems. I'd
suggest Atlantic 33, S1 or S7.
Pete Stanaitis
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Grant Erwin wrote:
Grant if you go down to Summerville steel in Kent you can buy small
pieces of tool steel that are better suited to hot cut tools, like A-2
or D-2.
They also carry some S steels which are the best for blacksmithing
tools.
S is for shock resistance.
S steels are mostly used for jackhammer bits and concrete drills.
If you're doing it on the cheap you can get a useable tool out of leaf spring,
pieces of which are generally available on the side of the road. You won't know
exactly what alloy you've got, so you're not going to get the optimum
performance out of that piece of steel, but it'll work.
I've been using a cutting hardy I made out of leaf spring for a _very_ long
time. I just curled one end up so it fit in the hardie hole and sharpened the
other. Originally I hardened and tempered it. I'm not sure that was necessary,
I've been using it for hot cutting ever since and have never re-hardened it. I
think I touched up the edge once.
If you can weld, I'm sure you can cobble up a top cutter using the same material.
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pieces of which are generally available on the side of the road. You won't know
exactly what alloy you've got, so you're not going to get the optimum
performance out of that piece of steel, but it'll work.
time. I just curled one end up so it fit in the hardie hole and sharpened the
other. Originally I hardened and tempered it. I'm not sure that was necessary,
I've been using it for hot cutting ever since and have never re-hardened it. I
think I touched up the edge once.
Leaf springs are 95% of the time SAE 5160. I use a LOT of 5160 in blades. It
should make acceptable hot tooling when heat treated. I know it makes a really
good shaping die set for the powerhammer.
Charly
For a cheap and fast cutoff hardy, weld a chunk of leaf spring to a
chunk of hardy hole sized stock.
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The bad ascii art is the side view. Bevel it to one side only and it
will be fast to resharpen, and will give you a nice square cut end.
The shank sits in the hole, the bottom of the spring sits on the anvil
face.
Unless you are doing heavy peices, the hot cut tools will mostly just
be in momentary contact with the hot metal. If you limit contact time,
and don't try to cut cold metal, the tools will last a long time.
Cheers
Trevor Jones
Sharp edge tools won't hold their edge becuse the thin edge heats up
very quickly. I use OCS for fullers and other non-sharp tools but have
found these steels less than good for hot-cutting.
Unless you have a fancy heat treat oven, use H-13. It is popular
amongst farriers because it is air hardening and can be worked using
standard blacksmith techniques. Forge it a little hotter than you
would mild steel and don't hammer after it cools. After you get your
shape, heat to bright cherry and let cool in air.
My anvil has a 7/8"+ hardy hole. The way I make my hardies is as
follows: I
bought a length of 7/8" square mild steel (you may need a different size
to fit
your hardy hole). I cut off a few inches of this - enough to stick out
the
bottom of the hardy hole a bit when the other end is flush with the
anvil face.
I forge the business end of my hardy out of appropriate steel. e.g. I
have a
hot chisel made from about 1-1/2" of H13. I strongly bevel one end of
both
pieces and TIG weld them together using 312 stainless steel rod - I have
done
this with oxy-acetylene before I had a TIG. I then wrap a piece of
3/16" or
1/4" rod around at the weld and weld that into position (upper side so
as not
to interfere with seating in the hardy hole). This saves a lot of
expensive
tool steel and works every bit as well as a one piece tool.
I have two hot-cut tools, on fro the hardie hole and one on a wood
handle for top cutting. Both are H-13 and have been quite satisfactory.
The steels Ernie mentioned are probably better but only if you can
accomodate their more sophisticated heat treatment requirements.
Ted
A splitting wedge is reasonably shaped, but a bit on the large side.
I think there are problems with the idea of using a hatchet. Hammering
on the back of a hatchet (for the one's I've seen) wouldn't last very long.
Steve Smith
Grant Erwin wrote:
A dandy starting piece of metal is a discarded pavement cutting jack-hammer
blade. I have several that I have used for that purpose. Sometimes they are
broken off at the wide ring section right where you most want them to be
intact, but often they are just discarded due to being well worn. The bigger
ones you can either grind or forge the shank square to fit your anvil.
Another good scrap item to start with is the male connector end of a 7/8" or
1" diameter piece of sucker rod. They already have a nice square shank
section with a collar ring that you just need to work down to fit your
anvil, then draw out either a short section of the rod, or the other end
with the threaded connector stub to make the blade. These don't make very
big hardies, but they are excellent steel and will work well and last your
life time. Sucker rod is wonderful metal for a variety of uses, especially
for specialty hammer heads. I make my Repousse' hammers out of sucker rod.
You can get the 7/8" rods that are 30 feet long here for $5-$7 each, and
that is a pretty good deal considering the quality of the steel. If you live
in oil well country you can probably get them for free. I have six of the
rods on my steel rack at this time, and they will probably last me the rest
of my life as often as I use them.
Ron
--
Golden Age Forge
http://www.reil1.net/gallery.shtml
Tue, 16 Dec 2003 15:00:47 +0000 (UTC), "Andrew Mawson"
The Sucker Rod Pump is believed to have been developed by the Chinese
around 400 BC. At that time bamboo was used for the barrel, and jade
or ivory was carved into spheres to make the balls which were set on
wooden seats. These pumps were used to pump water using a bamboo
sucker rod string.
Link showing sucker rod pump as used in oil industry. Windmill water
pumps use sucker rod pumps. Hand water pumps for deep wells are also
sucker rod pumps.
http://www.mit.edu/afs/athena/course/2/2.972/www/reports/sucker_rod_pump/sucker_rod_pump.html
On Tue, 16 Dec 2003 15:00:47 +0000 (UTC), "Andrew Mawson"
High strength steel rod used in walking beam pump. Links walking beam
with pump piston at bottom of well. 3/4" to 1" round steel rod is
commonly used. Around U.S. oil industry it is called a sucker rod.
Lifting rod would be better term as that pump doesn't suck.
That's the ones. Pump rod comes in 20 and 40 foot sticks IIRC, and has
threaded ends. It's probably a plain carbon steel, with a high tensile
rating to carry all the weight down the hole. (A half mile of rod can add
right up on poundage.)
I know it makes good hammers, we used them for everything in the field.
Charly
A useful source of steel for tools, especially hammers is forklift
fork. Comes in big sizes and is usually free for the asking at your
local forklift repair place,as they can't weld them if they crack or
break. IIRC they are often 4140 steel.
Geoff
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