| Drilling
the holes
After the blanks are cut to length, they must be drilled in order to accept
the brass support tube. The outer walls of the blank will eventually be
turned to approximately 1/16" thick–far too thin to avoid breaking!
The brass tube prevents this.
When I first started making pens, I simply used my fingers to hold the
blank while drilling. It worked fine. However, several cuts, abrasions
and part of a fingernail later, I got smart! The pen drilling vise used
here makes simple, safe work of drilling the blanks. Once set up–and
it’s easy to do–it provides a stable, accurate platform. I
placed a piece of scrap stock in the bottom of the vise to prevent the
base of the stock from being destroyed. Doing so also helps to prevent
the blowout that is common with Dymondwood and other similar materials
(see Fig. 3). Lock a 10mm drill bit in the drill press. Secure the blank
and drill through to the other side. Be sure to raise the drill bit often
during this process in order to clear the chips from the hole. Doing so
helps to prevent overheating. Test the fit now to be sure that the tube
does not stick in the hole. It’s too late once the glue has been
applied! If the tube does stick, I just re-drill the hole several times
until it does fit. (I really think that the problem is one of expansion/contraction
of the stock. If I have a particularly stubborn piece, I let it cool down
and then redrill.) As shown in Fig. 4, the top tube is usually pre-notched
for the pen clip. I disregard this notch.
Securing
the tubes
The
tubes are glued into the blank with a thick cyanoacrylate adhesive (superglue).
The easiest method is to place the tube over the metal tube installer,
squeeze the superglue over the tube and push it into position. I like
to sand the surface of the tube with very fine abrasive paper prior to
gluing it in place (see Fig. 5). I think that this removes any existing
surface oxidation and the resulting rough surface provides more tooth
for the glue and produces a far stronger bond.
Allow the glue to cure for at least 15 minutes. Often a small amount of
the superglue will accumulate on the interior surface of the tubes and
will prevent the bushings and/or the remaining parts from seating properly.
I use a small, sharp pen knife to scrape any excess glue from the interior
of the tube (see Fig. 6).
Finally, remove the excess stock from the length of the blank. I use a
chop saw and cut right up to, but do NOT touch the brass tube.
Dymondwood has a tendency to crack because of the heat generated by the
drilling operation. To insure that this will not become a major problem,
I flood the two surfaces that show the joints between the veneers with
thin superglue and give them a spritz of the accelerator to rapidly cure
the glue. The thin glue flows down into the small cracks and bonds them
securely (see Fig. 7).
Preparing
for turning
The tubes must be turned to the finished outside diameter on a mandrel.
The mandrel supports the tubes while securing them between lathe centers.
The bushings that space out the blanks and center them on the mandrel
also provide a gauge so you can determine when to stop turning. Set up
the blanks so they are separated by the correct bushings as shown in Fig.
8. A revolving, or live, center is mandatory for this project. The point
of the live center aligns with the depression in the end of the mandrel,
mounting the blanks between centers (see Fig. 9).
Turning
the blanks
I usually use a sharp skew to turn the blanks to their final diameter
because I find this to be much faster than using other chisels. Unfortunately,
I have had problems with the manufactured products chipping out, usually
destroying the blanks in the process. Therefore, I now use a roughing
gouge to turn the blanks so they are about 1/16" above the bushings,
and then I use the skew to finish the cut (see Figs. 10 and 11). If you
are not confident with your skew skills, use the gouge. (Note: I used
a 1-1/2" roughing gouge because I have nothing smaller. A 3/4"
or 1" gouge would be a much better choice.)
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