This article was passed to me in knifeforums, it used to be a page on Bob Engnath’s website, it’s about how to make custom mosaic pins, like the ones used in knifemaking
The tubes and rods, made by K & S Engineering, are made in 1/32″
increments, except for some odd sizes, and tubes generally have inside
diameters that fit the next size down without forcing them.
Hex and square tubes are measured across the flats. The
corner-to-corner measures are larger, so a 1/8th inch square tube will
not drop into a round tube that is 1/8th inch inside diameter.
The following odd-size rods have their uses: .020, 3/64, .072, &
.081. They may be used to fill in between larger pieces, or to steady
slightly loose assembly.
You can get almost any size of these rods and tubes, as long as you
want it in brass. Copper comes in four sizes of tubing, 1/16″ through
5/32″. I haven’t tried the many possibilities of brass rectangles and
angles.
After chasing this wild goose for much too long, I found a source
(Malin Co. Wire, 216-642-0208) for one foot lengths of straight
stainless rod in just about any size you want, as long as you order a
lifetime supply (or two) of one size. This product is a smidgenth
(willionth of a skillameter) smaller than 1/32″ K& S brass rod,
which is sometimes good and sometimes bad.
Blades ‘n’ Stuff sold brass and stainless thong-hole tubing and
fractional sizes of brass, nickel silver stainless, and nickel-silver
rods, 1/16″ and up. I haven’t tried the nickel-silver, because it’s
expensive and the 1/16th inch size bends immediately when I try to
force it through a tight space. Use rods that are straight enough to
roll on a flat surface, if you are assembling a foot at a time. 1/16″
stainless welding rod seems to be a smidgenth larger than 1/16″ K &
S brass or copper tubing. This is good in some assemblies, and not in
others. The 1/4″ brass and stainless thong hole tubes have thicker
walls than 1/4″ K & S brass tubes, and require experimentation.
An Inside diameter of three units (i.e. 3/16″ i.d. in an 7/32″ K
& S tube, or 3/32″ i.d. in a 1/8″ K & S tube) will fit seven
one-unit rods (or smaller tubes), six around the edge and one in the
middle. The middle position can be left vacant, and the six around the
edge will support themselves like the bricks in an arch.
If you find a tube and rod combination that fits five or less
around, the inside space will be smaller than the units in the outer
ring. A ring of seven or more goes around a larger inside space. For
example, five 3/64″ rods fit inside a 5/32′ K & S tube, with a
1/32″ rod down the middle. Seven 1/16′ stainless rods fit tightly
around the inside diameter of certain B & S 1/4″ stainless
thong-hole tubes; the middle space can be filled either with epoxy or a
.081″ K & S brass rod. Seven 1/16″ K & S tubes are a little too
loose in the same stainless tube, and won’t properly support themselves
without a center rod.
Some combinations work with a center rod and an outer ring of alternating large and small round rods or tubes.
Small rods of the appropriate size, between a round outer tube and a
flat wall of a hex or square inner tube should almost center
themselves, if the fit is so tight that it’s nearly impossible to
assemble. I have found that four pairs of 1/32″ stainless wires center
themselves along the sides of a 1/8′ square in a 7/32″ round tube.
Hex or square center tubes help avoid getting a rifling twist in the
outer ring, which is not good if you want the same alignment of the
pattern on both sides of the knife. Otherwise, one must push one pin
out the opposite end of the tube before the glue sets, and eyeball and
fiddle with it, to straighten the pattern.
You want long working time in your epoxy. I have lately been using
syringes (minus needles) to completely fill the tube from the end
opposite the pins, which were assembled dry and then pushed out eleven
inches from a one-foot tube. I push them back into the epoxy one at a
time. I end up wasting a fair amount of glue, and the wife has colorful
things to say about where stray black epoxy gunk turns up.
I have done a sample set. Depending on which way you are looking at it, this list may be forward or backward:
- 7/32″ K & S brass tube, six 1/16″ copper tubes, six .031 stainless.
- 7/32″ K & S brass tube, 1/16″ stainless rod, five 1/16″ copper tubes, ten .031 stainless.
- 1/4″ K & S brass tube, five .081″ brass rods, five .0031 stainless.
- 1/4″ K & S brass tube, 3/32″ hex, 1/16′ stainless rod, six 1/16″ copper tubes, twelve .031 stainless.
- 1/8′ K & S copper tube, six 1/32″ brass rods, one .031″ stainless.
-
7/32″ K & S brass tube, 1/16″ stainless rod, six 1/16′ brass tubes, six .031 stainless.
- 1/8′ K & S brass tube, three 1/32′ brass, three .031′ stainless.
- 7/32′ K & S brass tube, 1/8″ square, 1/16′ square, thirteen .031″ stainless, and profanity-tight fit!
- 1/8″ K & S copper tube, four .031′ stainless, four .020 brass, one 1/32′ brass. A little loose.
- 1/4″ Blades ‘n’ Stuff stainless thong hole tube (.020 wall?), seven 1/16″ stainless, seven .020′ brass.
- Bull’s eye! 1/8″ brass, 3/32″ copper, 1/16″ stainless. Simple poor-man’s mokume.
These hints and tips were submitted by Jim Mattis, local knife
craftsman and interesting character, who doesn’t mind sharing the
result of his experimentation.
We stock most of the illustrated pins, made up and ready to use in
one foot lengths. Prices are at the end of the pin stock section. Each
should easily make ten pins for a conventional thickness grip.
MORE ON PINS
There are times when just getting a pin through the darn hole can be a
lot more effort than you want to go through. You cannot, for instance,
get a 1/8″ pin through a 1/8″ hole without a lot of work, and even some
luck.
The problem is, getting the darn thing lined up and pushing straight enough to keep it from galling or jamming.
An old buddy, I regret that I’ve forgotten his name, gave me this one, and it’s a jewel.
He used a couple of flat, circular magnets, the sort you can find
without too much effort, for putting a heavy duty hook on the
refrigerator door. Get rid of the hook part, and drill a hole through
each, approximately through the center. Put a socket head machine screw
through each hole and grind it flat with the side of the magnet
opposite the head.
Now you have a couple gadgets to put in your vise jaws, that will
stay where you put them, are easy to line up and easier to remove when
you’re done. You want the hollows in the head of each socket screw to
line up, exactly, when the jaws are together.
If you’ll start a pin into the hole of your knife handle and put it
between the two magnets (while they’re lined up, in the vise), you’ll
be able to use the vise to clamp down and force the pin into the hole.
Since you’re squeezing between two steady and relatively fixed
points, the pin has to go in straight, avoiding all of the problems
that one runs into when trying to do this on the bench top with a
little block of steel, and the side of a crescent wrench for a hammer.
Well, there’s never a hammer at hand when you need one, is there.
AND MORE AGAIN
Precise pin setting.
Barry Wood showed us this gadget and it works really great. Most of us
just hammer the end of the pin. Well, Barry doesn’t. He uses a
precision guide and punches to form the ends of pins and does it so
neatly that you’d think that they were molded that way.
The guts of the gadget is a ‘C” shaped piece of steel, about 1.5″
thick and around 6 to 8 ” in height. This “C” should be like a plain
block letter, with the top and bottom parallel, the back vertical, and
all parts of about equal thickness, around an inch or a bit more. You
can actually use a large clevis link for this part.
In the sketch you see an anvil and a sort of piston affair above it.
The anvil is fixed in place, but the piston is free to move up and down
in a tightly fit hole drilled into the “C” frame. The center of the
piston is drilled lengthwise to fit snugly on a selection of shaped
punches. It’s the punches that do all the work.
Your knife, with pins protruding slightly, is set between the anvil
and the piston, with the clamp atop the piston tightened to hold it all
together firmly. You’l have to sight down the hole through the piston
so it will be centered on the pin you want to work on.
Once the knife and piston are clamped, use the chisel end punch to
begin spreading the pin. You tap gently, lift and turn the punch
slightly, then tap again. Keep this up until the head has spread a bit,
then switch to a concave punch, should you want a rounded head on the
pin.
It’s a good idea to start one side then go over and start the other side, before doing a lot of shaping on the first pin.
This gadget virtually eliminates all chance of folding over or
bending the pinhead and seems to concentrate the deformation of the pin
at the head, rather than down deep inside the assembly where it could
mess up the smooth action of a folder
Bob Engnath’s pages


I visit your web site when I am bored and I must say that I like your template!