How to Make 'X-ACTO' Knives
To All:
Often times we have the need to create small but accurate shapes in
metal or wood. When the 'part' happens to be in two dimensions
rather than three, such as a stencil (!) or an airfoil template, a
common method of making the part is to simply print it out then glue
the print-out to a piece of shim-stock and simply cut it out. The
usual tool for cutting out such parts is an X-ACTO Knife which comes
to a point (ie, the #11 X-acto Knife blade). But if you find the
cupboard is bare and elect to order the part via telephone, you are in
for a serious shock, which goes something like this:
X-ACTO item# TCL X411, Classic Fine-point Blade, 15ea, X-ACTO#11,
$5.99
Shipping
$6.95
CA Tax $1.06
TOTAL $14.00
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That's $0.93 PER BLADE.
Do this instead:
Find yourself some STEEL STRAPPING. Use your snips -- Dutchman or
regular tinner's snips -- to make ONE cut at a shallow angle, then go
about 2-1/2" down the strap and make ANOTHER cut... but at the
OPPOSITE angle. Go over to your BENCH GRINDER, the one fitted with a
pair of FINE stones, and SHARPEN the angles you've just created. Be
careful sharpening the OPPOSITE angle. With both angles ROUGHLY
sharpened, do whatever it is YOU do to FINISH the sharpening... but
only go through HALF of your finish-sharpening procedue. That is, you
want to leave the edges NOT QUITE FINISHED. Now cut the pieces
exactly in the MIDDLE and you've got TWO pieces that look kinda like a
#11 blade.
You might as well make up a dozen or so PAIRS.
If you do any metal work at all you probably have used a 'bomb' to
convert MILD steel into High Carbon steel. The 'bomb' is nothing more
than a NIPPLE of black iron pipe with a pipe CAP on either end. For
little blades like this... or little screws or whatever... your 'bomb'
is probably about three inches long.
Chuck the 'bomb' into your bench vise and pour about an inch of
CHARCOAL into the thing. Now pack the BLADES into the charcoal. Heap
it up. Then pack charcoal into the pipe cap and screw it on. Hand-
tight is fine.
I've found the best charcoal for this is made from old LEATHER. Other
common gunsmithing charcoals are made from BONE and so forth. And
don''t laugh at any of this. What's happening is that the different
charcoals contain TRACE ELEMENTS which makes them more suitable for
springs; for hammer faces, for frizzens, fasteners and so forth.
The TRACE ELEMENTS, along with the CARBON is infused into your MILD
STEEL part when you put the bomb into your forge, bury it in coke or
charcoal, and blow-up a good blaze. Don't rush; take your time. You
want the bomb to reach a BRIGHT YELLOW heat.
Once you've reached the proper temperature, you want to keep it there
for about ten minutes for a small bomb (ie, one made from 1" pipe, 3"
long. Larger (or smaller), work out the required heat by comparing
the VOLUME of the bomb divided by its radius. ( A BIG bomb is
something on the order of three inches in diameter by a foot in length
-- it'll take you a couple of HOURS to properly infuse the part(s). )
Use your tongs to pull the bomb out of the coals, and another set of
tongs to unscrew one end. Do this right on the edge of the forge and
right ABOVE a bucket full of old motor oil. Now tip the contents of
the bomb into the bucket.
The bucket is going to catch fire. Don't worry about it. Put a cover
over the bucket to smother the flames. Stir the contents of the
bucket a few times then wait until the oil is cool enough for you to
fish out the blades.
Collect all of the blades in a shallow pan and cover them with an
eighth of an inch of motor oil. Now set the oil on fire. Allow the
fire to burn out. It's going to be smokey as hell so you want to do
this outside of your shop. When the fire goes out, tip the blades out
of the shallow pan onto a piece of iron and allow them to cool.
Once the blades have cooled you may continue with your sharpening.
They should take a razor edge. If they crack, you've either left them
in the bomb too long or you've cooled them too fast. The tempering
(ie, burning-off) should not effect the cracking one way or another.
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That's how you make blades (or leaf-springs or what-not). To make a
HANDLE for your blade simply cut a slot in a dowel or a piece of
pruning from a hardwood tree or shrub, and affix the blade in the slot
using EPOXY. Epoxy holds the blade strong enough for most work but
for metal engraving or wood carving, you'll want a more secure joining
between the handle and the tool. You can achieve this drilling a hole
(or holes) into the blade BEFORE the hardening, and affixing the blade
with steel or brass pins.
To add a bit of class to your burrens, gravures, knives and what-not,
you can fit them with copper or brass ferules. (Looks very sexy to
have an ENGRAVED data plate instead of some Joe Sixpak array of
stamped letters & numbers.)
-R.S.Hoover
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