[CW] A question on Vibroplexes

[D.J.J. Ring, Jr.]

JAPANNING A KEY BASE

To Refinish Or Not To Refinish — Again I feel the need to remind the reader
that it is not the intent of this book to encourage anyone to do any of the
operations described. Rather, the purpose is to offer successful ways to
accomplish those tasks if the reader how to refinish the badly damaged
japanning of a speed key base such as shown in Fig-1. Speed Key Base
Finishes — Before the advent of modern paints, japanning was used very
often as a treatment for the protection of metal surfaces. Ford used it on
the Model T and Singer used it on the foot-pedaled sewing machines. Many
speed key bases also were japanned. The slightly more expensive key bases
were nickel-plated. The japanning varnish formed a very hard, jet-back
coating that was durable and had a most attractive high gloss surface. The
fact that keys can be found today that are 100 years old and still have a
good finish is a testament to its durability. The history of japanning and
its major component, asphaltum, is a rather interesting story. Asphaltum —
This material is said to have formed in vertical veins about one million
years ago when a viscous hydrocarbon lost its volatile constituents and
solidified into a glossy, black, solid hydrocarbon. Its appearance is
similar to coal. It is brittle, lightweight, can be crushed and, depending
on the grade, melts at between 300 and 400 degrees F. A vein of it was
discovered in Utah by Samuel Gilson in 1885 and he named it Gilsonite. Its
first uses were for painting buggies, lining beer vats and waterproofing
lumber for docks. Since then, its uses have grown amazingly. However, other
more modern materials have replaced its use as a metal coating. The Varnish
— Some of the earlier formulas for japanning varnish required the melting
of asphaltum at 350 to 400 degrees F during the mixing with turpentine—a
rather dangerous exercise. It is likely that this was needed because, at
that time, the asphaltum came in lumps like coal. However, it can now be
purchased in powder form that has been processed to remove rock and other
contaminants. This allows cold mixing in the home workshop. I know of no
reliable source for true japanning varnish. The literature offers a
confusing number of formulas for japanning varnish. The one that has proven
to be the easiest to mix and use is a cold mix, consisting of 2 parts of
boiled linseed oil, 5 parts of turpentine, 3 parts of asphaltum powder and
3 parts of rosin. Lamp black or carbon black is sometimes added but they
are not needed for key base use and usually cause more problems than they
solve. It is wise to mix the varnish outdoors 1 3 wishes to perform them.
The object of this chapter is to illustrate Fig. 1. The Base To Be Japanned
because the smell is a lingering one. Containers of asphaltum and rosin are
shown in Fig. 2. At the time of writing, one of the firms from which the
asphaltum and rosin can be purchased is Rembrandt Graphic Arts Company
(Ref. 1). Some users of home- mixed varnish have reported that a smoother
finish results if no rosin is ROSIN Fig. 2. Containers Of Asphaltum & Rosin
added to the mixture. Numerous tests in my own shop have shown this to be
quite true. To avoid clumps while mixing the varnish, add very small
amounts of asphaltum to the turpentine while stirring. Add rosin in small
amounts after all asphaltum has been dissolved. It has been suggested that
warming the mixing bowl over boiling water shortens the mixing time
considerably. However, it will be found that to obtain a smooth
consistency, a considerable amount of mixing time is required. After
mixing, it is wise to strain the varnish through a couple of layers of
reasonably close-knit, lint free, cotton cloth to remove grit and any
undissolved components. Be extremely cautious handling items wet with
linseed oil. This material is spontaneously combustible and could easily
start a fire. Never put waste saturated with it in a wastebasket.
Straighten the pieces of cloth or paper and lay them outside to Fig. 3.
Japanning Varnish & Brush dry before disposing of them. Figure 3 shows a
small jar of home-mixed japanning varnish and a soft bristle (camel’s-
hair), brush for applying it. These brushes are available at most art
supply stores. If unavailable, most any soft bristle brush can be used.
Clean with paint thinner. Preparing The Base —The old japanning varnish on
speed key bases can be removed easily in fifteen to thirty minutes with
most commercial paint removers. Prepare the base for this as follows. After
the hardware and feet have been removed, straighten the brads and remove
the label. These are simple dome-head, brass brads that have been annealed
by the factory for easy bending. On the bottom of the base, slip a wood
chisel under the bent end of the brad and lift it enough to be gripped with
a pair of flat nose pliers. Do not allow the chisel to mark the wall of the
brad. Straighten it as much as possible and drive it free of the base. If
the wall of the brad has not been scored with the chisel, and does not
crack while being lifted, it may be possible to anneal and reuse it later
when reinstalling the label. 1 4 Figure 4 illustrates the lifting of a brad
with a small wood chisel. Some brads are not bent but are large in diameter
and have their ends bradded on the underside of the base. Most, however,
are of the brad type and are bent on the underside of the base. All I have
seen are brass. Removal of the old japanning is best done outdoors near a
water faucet. Place a bent wire in the bottom of a loaf pan, to space the
base from the pan so the paint remover can easily reach the underside of
the base, Fig. 5. Place a wire through one of the holes in the base for
ease of handling. Be certain Fig. 5. A Loaf Pan with Bent Wire Fig. 4. Brad
Removal to wear eye protection. There is a great danger of the base
slipping during handling and causing the paint remover to splatter. For
this reason, the handling wire is an added protection. Wear rubber gloves
and avoid all skin contact with the paint remover. It is a very offensive
material, burns the skin almost instantly and could cause blindness Lay the
base on the bent wire in the bottom of the loaf pan, Fig. 6, cover it with
paint remover and allow it to stand for 15 to 30 minutes. By then the
varnish should be free enough to be pushed off the surface with a brush. In
stubborn cases, it may be necessary to discard the old paint remover and
apply a fresh coating for a longer time. When all the old varnish has been
6. The Base In The Pan Bl removed, rinse the base thoroughly in tap water
and use a toothpick, or other object, to clear the dead paint from inside
the holes. Dry in a toaster oven at 150 degrees F for 30 minutes. The base
stripped of the . japanning is shown in Fig. 7. Smoothing — Key bases are m
usually cast iron that has been poured in a sand mold. This often Pjd je.
leaves sharp pips in the surface. These cause problems by sticking - •*'' f
C'il through the various coats of |ic s •: japanning varnish and they
should s . be removed. A very simple way to do this is to lay the base on a
board Fig. 7. The Stripped Base and drive finishing nails around it to
prevent it from moving. Paper the surface with an orbital sander and
100-grit emery paper. This is only to remove the sharp points that could
stick through the varnish. It would be unreasonable to try to remove all of
the sand mold marks. Key makers seldom made any serious attempt to remove
the marks before japanning their bases. 1 5 iHv Fig. 8. Papering The Base
The setup for papering a base is shown in Fig. 8. Using wet or dry paper
and water speeds up the process but is very harmful to the orbital sander.
At times, one encounters a base with cavities in the casting. These can be
filled with Lab- metal before japanning . This material will withstand the
baking temperature and comes in two temperature versions, 350 degrees F and
1000 degrees F, and has a very short shelf life. A can of each type is
shown in Fig. 9. It can be purchased from Alvin Products (Ref. 2). Rust
Removal — By far the best rust removal method for a cast iron key base or
steel base is by electrolysis. This is a simple process and can be done by
anyone. Purchase a typical wall-wart having an output voltage of 6 or 12
volts DC and at least 1/2 ampere current capacity. Also, a container will
be required to hold the electrolyte solution. Since the electrolysis action
does not affect 18-10 stainless steel, I purchased such a bowl used in a
plastic container but it is difficult to arrange Fig. 10. Rust Removal From
The Base Fig. 9. For Patching Casting Holes from Wal-Mart. Iron plates
could be such plates to completely surround the base for the line-of-sight
action desired for electrolysis. Thus, I prefer the solid container of
stainless steel. Suspend the base on two wires from a wooden rod laid
across the top of the container. Connect the negative lead from the
wall-wart to one of these wires. (A red alligator clip is the only color I
had.) Attach the positive lead either to the iron plates submerged in the
solution and spaced around the base or to the stainless bowl. A base
arranged for de-rusting by electrolysis action is shown in Fig. 10. The
Electrolyte — Mix a solution of one tablespoon of washing soda (sodium
carbonate), not baking 1 6 soda (sodium bicarbonate) to one gallon of
water. Cover the base with this, plug in the wall-wart and look for bubbles
rising from the base. If none are seen, check for a poor connection. The
action is self-limiting and can be left unattended for extended periods.
Drying — After de-rusting, ferrous metal will begin to rust in about ten to
fifteen minutes. It is imperative that it be dried properly and quickly.
Remove the base from the washing soda solution and rinse it thoroughly in
water. Dry it on a towel and rinse it in denatured alcohol, dry with a
towel again and place it in a toaster oven at 150 degrees F for about
30-minutes. When cool, the base is ready for the application of the
japanning varnish. Japanning The Base — In each of the foot screw holes,
install a screw that protrudes about 3/4" from the bottom of the key base.
Lay the base upside down on a piece of clean paper. Using a 1" or 3/4" wide
camel’s-hair brush, apply a uniform coat of japanning varnish to the bottom
of the base. (It is best not to stir the varnish before use. Some of the
offensive material, missed by the straining and settled to the bottom,
could cause bumps in the varnish if stirred.) Do not try to apply excessive
varnish or it will form droplets on the bottom side of the base that must
be removed with a knife after baking. Turn the base over, stand it on the
screws and apply varnish to the edges and then to the top surface. There
are two choices before starting the baking cycle. The base can rest in a
dust free place for two days or it can be taken directly to the toaster
oven, Fig. 11, at 125 degrees for 2-1/2-hours. I prefer to go directly to
the oven and allow the low heat to do the same job of evaporating the
volatiles that resting at room temperature for two days does. Set the base
on a 1/16" thick sheet of steel and place it in a toaster oven. This first
stage cannot be rushed. If too high a temperature is applied to the base
before the remaining volatiles have had time to evaporate, large bare spots
or brush-like streaks will appear in the varnish. Figure 12 shows a large
bare spot on the base caused by this. Most instructions for japanning state
a baking process with a cooling period between bakes. My experience has
shown that cooling between bakes is not required. Thus, I go directly from
one baking temperature to the next. This avoids a great loss of shop time.
After the 2-1/2-hours in the 125 degrees F oven, it is time to start the
baking cycle. Set the oven at 150 degrees F and bake for 1-hour, then at
200 degrees F and bake for 30- minutes. Next, bake at 250 degrees F for
30-minutes. Follow this at 300 degrees F for 30-minutes, and finally 350 F
degrees for 1-1/2 hours. When cool, it should not be possible to mark the
japanning with the 1 7 Fig. 11. The Toaster Oven & Key Base Fig. 12. Temp
Too High Too Quickly Fig. 13. The Support Screws fingernail. If it can be
marked, return it to the oven for a longer bake at 350 degrees F.
Experience has shown that a minimum of five coats of varnish will be needed
for a good finish. Each coat requires the same complete baking cycle.
Figure 13 shows temporary feet (tapered screws) for handling and supporting
the base during the varnishing and baking process. Quite often, small
inclusions appear in the varnish as minute grains after a baking cycle.
When they occur, they must be removed. Wrap a small patch of 600 grit, wet
or dry emery paper around a half wine cork (sawed axially), Fig. 14. Wet
this and rub the surface to remove them. This should be done following each
baking cycle. At times, varnish will be stripped off the brush Fjg 14 Emery
Paper & 1/2 Cork as it crosses the holes in the base. This excess varnish
will collect as a drop on the bottom of the base and will not cure during
baking. Cut these off smooth with the surface with a pocket knife before
each baking cycle. Figure 15 shows a muslin buff, an arbor for chucking it
in a drill motor, and tripoli and red rouge polishing compounds. Clamp the
drill motor in a bench vise to simulate a buffing machine and use the
polishing compounds on the buff to produce a highly polished surface. After
buffing, thoroughly wash the base with detergent and water to remove the
polishing compounds and dry it in a toaster oven at 150 Fig. 15. A Buff,
Arbor & Dressing degrees F for 30-minutes. Figure 16 shows the japanned
base. The Pin Stripes — There are a number of ways to pin stripe a base. I
have used a draftsman’s ruling pen and gold paint and also a commercial
gold paint pen from an art supply store. Each of these work but I prefer
the latter. To simplify the pin striping effort, a homemade ruling guide
must be made to guide the pen while drawing the stripes. It must rest
against the side of the base to provide a straightedge that stands above
the surface Fig. 16. The Japanned Base 1 8 Fig. 17. Top View Of
Straightedge of the base and serves as a guide for the pen. Figure 17 shows
such a device. It is composed of a wooden base, a 1/16” thick brass spacer
and a 1/32” thick brass top strip. This top strip can be positioned and
locked from 3/8" to 1/2" inward from the edge of the base to guide the pen.
The spacer positions the straightedge above the surface of the base to
prevent the guide from touching the paint. For the same reason, the spacer
must be shortened to a dimension less than the distance between the pin
stripes on the ends of the base. This will allow the guide to be put in
position for drawing the long stripes without smearing the freshly drawn
end stripes. Figure 18 shows the underside of the ruling guide, as
described above. The pen used for the pin striping is called a paint pen.
It is available from art supply Fig. 18. Straightedge, Bottom View stores
in larger cities or from Sandford Company (Ref. 3). It contains a gold
liquid, which is probably a lacquer. Adjust the top strip to position the
guide at the desired distance inward from the edge of the base. Position
the guide across the Fig. 19. Drawing The End Stripe end of the base, as
shown in Fig. 19. Shake the paint pen vigorously to mix the paint, place it
against the straightedge and draw the gold line. Move the guide to the
other side of the base and draw the other line there. While the end stripes
are still wet, lay the straight edge against the long edge of the base,
Fig. 20, being careful to center it so the spacer will not touch either of
the freshly drawn end stripes. Also, do not let the guide tip over and
touch the wet end lines. Draw the pin stripe on one side of the base and
then the other. Allow these stripes to dry for about 30-minutes. Use the
paint pen to draw the tick marks inside the stripes.
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