Paul Heuer has asked about how I made the heater control bezels, in case
any one of you would like to do the same. Here is what I did, as closely as
I can remember.
Start with 3/16" sheet Plexiglas. Cut strips 13/16" wide by 12 1/2" long,
leaving the paper on both sides of the strip. A band saw does this best.
Trace onto one side of the strip the positions of the screw holes, the
slots, and the rounded ends. If you don't have at least part of an old
bezel let me know and I can mail you a tracing.
Now drill the three holes for the screws. Do not use a drill out of your
set. You need a drill specially shaped for drilling acrylic. The size for
the screw holes is 3/16" and you may be able to get the right drill at a
hobby shop or from a tool catalog.
Now round the ends to match the tracing. I did this on a sanding disk.
You need, at this point, to make a jig to hold the piece while you cut the
slots and cut the concave surface. The jig is made from a piece of flat
wood about 5" x 24" by cutting a groove in it the exact width of the
Plexiglass strip, so that the strip fits in snugly but can be pushed along
the length of the groove. A little experimenting with a dado head will do it.
The slots are cut with a drill bit of the kind that is used for cutting
irregular shapes out of thin wood or wall board. It is 1/4" in diameter
with cutting teeth all around the entire shaft. I don't know what it is
called but it is readily available. With the piece in the jig, and the jig
clamped to the table of a drill press, line up the marks for the slot with
the drill. Cut down into and through the piece, then cut the slot by
slowly sliding the piece in the jig against the drill. Repeat for the
second slot.
The concave surface is formed by a round nose bit of 1 1/2" diameter. You
can find one in a woodworker's catalog. The bit is placed in the drill
press and the jig lined up so that the tip of the bit comes down about
on the center line of the piece. Take a light cut by sliding the piece in
the jig, then adjust the position of the jig to get it perfectly centered.
Take repeated small cuts until the concavity just touches the borders of
the piece at the sides and ends.
Now you are ready to start working. The piece must now be polished with
increasingly fine sandpaper to remove the scratches and rough surfaces. The
back does not need to be touched since it is still protected by the
original paper coat. The inner sides of the slots are polished with
sandpaper glued to flat sticks, and the rounded ends of the slots with
sandpaper glued to a piece of dowel.
I polished the concave surface with a tool called a profile sander, which
has sandpaper clipped to variously shaped rubber pieces, and enables you to
sand the curved surface. It can be done by hand with sandpaper wrapped
around a dowel, but will take forever.
Once the piece is completely smooth (many, many, hours) final polishing can
be done with a canvas polishing wheel and white rouge. After the first
polishing with rouge you will see areas that are not yet scratch free. More
fine sanding and then more rouge polishing.
When you are satisfied that the piece is perfectly polished the screw holes
should be slightly countersunk. Do not use a countersink meant for wood. It
will crack the plastic and destroy the piece. I used a small tapered stone
in a hand grinder and used only light touches. The countersink need not be
deep, a very shallow one does fine.
At this point I took the pieces in to a professional silk screener with
part of an old bezel that had a few of the letters still on it. They were
able to silk screen on the white letters and then paint the back and edges
of the pieces glossy black. The finished bezels could not be told from the
originals unless they were side by side, when a very slight difference in
the size of the letters might be seen.
You want to do the silk screening yourself? You will need to have had at
least a little experience in making a screen using photosensitive
materials, at the minimum. I could do it but thought a professional job
worth the money. If you are desperate for instructions on doing the
screening yourself, let me know.
Now having read all of the above I think you can see why I am not eager to
go through that drudgery again.
Fred Levit
Wilmette, IL. USA
fle426@northwestern.edu
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