Speaking of cracking things apart with razor blades, I was amused but
also  rather saddened to see in the latest AMICA Bulletin that someone
has gone to the enormous trouble of making new Duo-Art expression
boxes, it would seem, because he could not get them apart without
destroying them.  It is very easy to do so.

After removing the long screws holding the box together, simply use a
combination square to mark the exact location of the seam, and drive
dozens of single-edged razor blades into this seam with a hammer (be
careful that fragments do not fly into your eyes - wear goggles!  and,
of course, be careful not to get cut).  I save all used razor blades
for this type of job.  This technique works well with many other
situations in which a wood joint must be broken without damage.

Drive more blades alongside the first ones -- then, drive more blades
between the pairs of blades in the seam, all around (as wedges).  When
internal pressure is sufficient, you will hear a satisfying "crack," as
the box cleanly separates in two, with minimal or no damage to either
surface!

Both surfaces must now be sanded optically flat, for a flawless joint
during reassembly.  I am a devotee of the large disc sander for this (I
use a 16" disc); a belt sander cannot be trusted to achieve the
necessary accuracy.

If no disc sander is available, tape sheets of sandpaper to plate glass
or polished marble, granite or the like, burnishing the masking tape
firmly with a rounded object,  and sand against these.  60 grit is
adequately fine for a glue joint.  Pencil the surfaces repeatedly while
sanding so that you can see if the marks all disappear evenly, which
proves flatness.

After resealing the pouch wells, re-pouching, and after first providing
an anchor on the leather for the glue which must hold on the valve
buttons, then sealing the new pouches, mark the valve seats so that the
buttons can be centered on them.  With seats facing up, set the valves
centered on their seats and apply glue to them.

Have a 7/32" tube ready to blow into the pouches; set the pouch board
upside down onto the other half of the box, align the two halves to
perfection, and blow hard into the pouches; then wait for their glue to
set a bit (I prefer fish glue for this -- it grips quickly to leather)
before turning right-side up and pressing the buttons firmly onto their
pouches for good adhesion.  In this way, the valves will be perfectly
aligned to their seats.

Now apply fish glue to the edges of the valve seat side of the box and
assemble the two halves.  Pull the box apart once to be sure that a
perfect glue print with a small amount of squeeze-out is left on the
pouch board, then proceed with final assembly and install the screws.
The internal theme and crash valves of your Duo-Art expression box will
now be good for another half-century or more of operation.

If you wash off the excess glue on the outside of the box before it
dries, no one will be able to tell, however, that you ever opened the
box; so they will just have to take your word for it!  This is the one
problem with doing factory-grade work -- if done right, it looks like
you just cleaned up the original parts and did no restoration at all!

You can always tell a "rebuilt," but not truly restored, job -- it will
look like a '59 Cadillac, ripping with chrome; hideous, misshapen new
cadmium-plated screws from the Orient will everywhere have replaced the
dignified (and far superior in strength) original steel; nickel-plated
tuning pins will have supplanted the reserved and refined deep blued
originals; every plate screw originally painted will have been plated;
and instead of black shellac with its ripples and imperfections, you
will find sleek, smooth black acrylic lacquer, usually looking more
gray than black.

Shiny objects amuse children, and that is what some of us think of our
customers, I guess.  Maybe they are right, but I have always aspired to
raise the standard where possible, and educate the customer to
appreciate it, rather than catering to the baser tastes of the public.

Larry Broadmoore