Round drill rod (tool steel) is good to
have around for making various tools. It comes as water hardening,
oil hardening and air hardening which is a reference to what is used to
quench it in after heat treating. Drill rod is inexpensive and comes
in many diameters. 3/32" and 1/8" round
is probably the most useful for engraving. Both of these will fit in the
AirGraver if it is desired to use it there. Otherwise for hand scrapers and burnishers a
handle can be made using a wood dowel, 1/4 or 3/8" diameter. Drill a hole
in the end of the wood dowel to accept the drill rod shank. Another
option for scrapers is to use an old small triangle file and shape the
three corners towards the tip so they are sharp. Files are made from
tool steel (drill rod material). Scrapers are used for shaving metal off
and are good for helping to smooth up a sculpted engraving.
Link to 3/32" drill rod
Link to 1/8" drill rod
scraper picture here...
The above picture
is a handy shape for a burnisher. Use a bench grinder to rough
grind the shape and then begin sanding with sandpaper going through the
grits until a fine finish is achieved. Harden it by heating it with a
torch until it is bright cherry red and quench the tip in oil, vegetable
shortening works well for the oil. For a burnisher
don't draw the hardness back but leave it full hard. Since it
isn't used like a punch there is no shock and we might just as well keep it as
hard as possible. Now take it to a buffing wheel and place the
final polish on it. You'll probably only need to make one of these
in your life because they last forever. Just rub it on some polishing
compound once in a while to keep the working surface fully polished.
A burnisher is used to smooth the metal out. For instance if you
were to slip, the resulting scratch displaced the metal more than cutting it.
A burnisher can push the displaced metal back into the scratch. A
burnisher is an engraver's eraser. If a scratch is deep, it may not totally repair it, but it will probably make it
better. After burnishing a scratch it may be necessary to polish
or sand the surface to the original state. A cut line mistake that
has metal missing is not very repairable. A change in the design or sanding the engraving off to lower the original
surface may be the only way to fix it.
Matting punch picture here....
I prefer to use the rotoary tool with one of
the custom made burs for making the matting surface in the background.
However, the usual method is to make a single pointed punch on the end
of a square graver and tap it with a hammer 5000 times. If you
have a larger area this can take forever so it may be time effective to
make a multiple dot matting punch. To make this use a piece of
drill rod. Flatten the end and engrave a checkering pattern on the
end. Engrave a row of lines one direction and another row of lines
another direction. Try to make the diamond shapes this creates
come to a full point. Now harden the end of the punch by heating
it with a torch until it is bright cherry red and quench the tip in oil,
as stated above, vegetable shortening works well for oil. The end is now fully hard.
You'll want to draw the hardness back some because if it were used at full
hardness, it may break. To draw the hardness back polish or at least
shin up the metal on the shank right next to the point. Next, with
a torch heat the punch while watching the color of the polished area.
When the color changes to straw color, stop. This temperature is
around 300 to 400 degrees. Be careful to heat it very slowly so the
color doesn't go much beyond straw. If you reach a blue color this
is call "spring temper". Spring temper means it is a good hardness
if we were wanting to make a spring. We'll want it a little harder
than this so the multiple points don't go dull during use.
If it is heated too much and you get in the blue color you'll have to re-harden it by heating it to a bright cherry red color, quenching in oil
and then temper it again.
If you don't have a
Rockwell hardness tester, an easy way to check the hardness of something is
to try to file it. If the file can cut it you know it is softer
than the file. A file is around 60 Rockwell C. Full hard O1
can range from 62 to 65. When we draw it back to a straw color we're
aiming for 55 to 60. A spring hardness (blue color) is around 40 to