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From: BluesGe~ol.com
Date: Wed, 17 Mar 1999 07:52:59 EST
Subject: Beeswaxing (a technical walk-through)

A little help is provided for beeswaxing Marine Band combs.

The following is condensed and reorganized from posts I made in December. (Is
it Spring already? Not in Hartford.)

The process is to use beeswax to seal the wood comb and to replace reed plate
nails with screws and nuts. This very inexpensive and easy procedure renders
an instrument that plays like butter, is completely leak-free, has a comb
which will not swell and shrink (much), but which feels like a natural pear
wood comb, has ideal compression, even response, surprising timbrel
accessibility, while still retaining, and even enhancing the idiosyncratic
Marine Band performance feel and sound.

The waxed combs can be played immediately, unlike other sealing methods which
require long cure times. If you mess up with the wax, you can just redip the
comb and quickly fix the comb surface. The wax is non-toxic. You have a harp
that can be conveniently dissasembled. When the wax deteriorates with age, it
can be retreated in just a few minutes, with little effort, and almost no
cost.

Disclaimer: While I am very excited by the results, and especially by the ease
and simplicity of attaining them, YMMV. It is entirely possible to ruin a harp
by accident. If you don't like the result, I might suggest trying again, but
please
don't blame me. OTOH, if you like what you get, send me half your money and
your first born child. Either way, please let me know what you think.

For best results use a new harp. Although you may wish to practice this on an
old
beater first.

If anyone has any questions or comments, please post to the list so all may
benefit.

I've described in detail all that I have done. In this way, even those who
have
never worked on an MB can enjoy this enhancement. Others may find some of this
post a bit tedious, or may wish to vary the procedure.

- -dave therault

Tools and Materials:

For comb prepping-

utility razor
pen knife
080 X 3/8" or 7/16" screws, with nuts
sandpaper (grades 400, 600, 1200, 1500)
true flat sanding table (inexpensive suggestion: 1 square foot polished marble
tile)
small screw drivers (and/or nut drivers)
electric drill or dremel
1/16' drill bit
small fine file
a small countersink (such as provided in the Farrel reed replacement kit)
needle nose pliers
punch
4-5 inch long rigid bar, true flat

For waxing-

1 lb beeswax
1 small saucepan
feeler guage
round toothpicks
popsicle stick or nail file
clean, soft, lint-free cloth (I use my shirt ...clean enough)
1 Marine Band

Procedure:

[If you already have a method for converting nailed MB plates into screw and
nut jobs, or if you are working on Blues Harps, you may wish to skip to step
7, and ignore any future references to drilling for screws and nuts. If you do
not wish to tamper with the original Hohner finish on the leading edge of the
comb, you can skip all the way to step 18 and 19, complete them and skip to
step 26, and be finished in just a few minutes. You'll have a nice harp, but
it'll still be subject to the inevitable breakdown of the Hohner finish. The
majority of this post addresses the preparation of the comb.]

1. Remove covers, and remove the two forward nails in each cover. Replace
covers.

2. Drill through the empty nail holes and completely through the harp.

3. Remove covers and remove the remaining nails. Replace covers and fasten
with screws and nuts in the two drilled out holes. [A note on screws: Screws
of a wider diameter than 080 are often used to fasten cover plates, for
example in the Special 20, and you may wish to do so yourself. The length of
3/8" is ideal for fastening the plates alone. You may wish to go to 7/16" for
fastening the covers. Round head screws are advisable, as the screw driver
holds better that with flat heads.]

4. Drill through the two remaining empty nail holes.

5. Remove covers.

6. File or grind off the burrs created by drilling on the underside of the
covers.

[For a very fast method, that does not involve taking off the stock MB finish
on the leading edge of the comb, skip to step 18 and 19. (Heck you're almost
done.)]

7. To remove the finish on the comb, place a fresh piece of 400 grit sandpaper
on the sanding table. Sand the front of the harp, taking material off the
front edge of the reed plates, being careful to apply even pressure, and
checking frequently for signs that the front edge of the comb has begun to
contact the sanding surface, and beginning to remove the finish fron the comb.
Always be careful when in any way apply force against the delicate partitions
of the comb to avoid breaking. (Broken partitions can be reattached with epoxy
to give a very strong joint.) VERY IMPORTANT: Carefully watch not to remove
too much brass from the front edge of the plates, compromising the channel
that receives the cover.

8. Gently sand, in a fashion to create a bevel and soften the now very sharp
edge on each plate. Very little sanding removes a lot material very quickly at
this step, so be very vigilant.

9. Remove all the nails from each plate, except for the four in each plate
that fasten next to where the cover nails attach. [The method I have used is
to loosen the nail by carefully sliding under the head with the utility razor
blade. Force the blade to the shaft of the nail. This lifts the head a bit,
without levering (and risking breaking) the delicate blade. Slide the pen
knife blade under the head and lever it up a bit. It may lift up completely
and easily. If not, once you have enough lifted, hinish the removal by pulling
with needle nose pliers.]

10. Place harp with blow reeds down on a surface which can be drilled into.

11. Very slowly, drill a hole through each of the three nail holes at the back
edge of the draw plate, taking care that the drill does not slip into the nail
holes of the blow plate, but cuts new holes in that plate.

12. Remove all remaining nails. Disassemble the plates and comb.

13. Carefully sand the sharp edge of each plate that joins to the comb, that
has been cut by the sanding in step 7.

14. Sand the front edge of comb on 400 grit paper, in the same manner as in
step 7, this time without the plates. The partitions are especially vulnerable
to breaking at this point. Another reason to sand lightly or moderately is to
avoid putting deep sanding marks on the wood. Watch to make sure that you are
holding the comb at a perfect 90 degree angle to the table. Apply even
pressure along the whole length of the harp. Sand until almost all traces of
the factory finish are removed from the front edge, making sure that the
finish is coming off evenly, adjustly pressure to accomplish this. It is very
important to be careful in this regard and in the next sanding steps, to avoid
changing the shape of the comb or making uneven in any way. It is very easy to
mess up in sanding. Flat surfaces, continually fresh sandpaper, good support,
and even pressure are critical. Take special care not to sand to much, even if
you have to stop before the finish is completely removed, as you can cause the
comb to become too recessed from the plates upon reassembly.

15. Using a popsicle stick or nail file for backing, use 600 grit paper to
"break" or round the front edges on the sides of the partitions. This gentle
beveling or rounding will make for more comfortable sliding, especially for
the tongue. It is important to use 600 grit paper to avoid making deep
impressions in the wood, which the tongue will find undesirable, and to avoid
taking off too much material. Be sure to support the partitions between thumb
and forefinger while applying the side torque with the sandpaper. Don't want
to snap one off now.

16. Using the same tools as in step 15, sand the inside of the channel of each
partition of the comb to about 1/8" in, again to create a surface the tongue
will not find rough. For some reason, the application of wax to a rough and
unfinished surface can create a very noticeable draggin sensation on the
tongue which is eliminated by properly surface the wood.

17. Repeat steps 15 and 16 only using 1200 grit paper, and then again with
1500 grit.

18. Lay the comb on its side on 400 paper. The comb is very flexible in this
position and it is very easy for the pressure applied by a finger to create a
uneven removal of wood, which will surely result in a bad comb/plate seal.
Place a rigid flat bar on the top to avoid this and ensure even pressure
during sanding. You may wish to light rub some carbon paper on the side of the
comb, which will quickly reveal where all the high and low spots are on the
comb, sanding until all the carbon ink is removed. I have not used this
method, instead using the removal of the mill marks in the wood as my guage.
Please note also, that because the comb has more material in the solid area at
the back and less in the area of the partitions, and more material where the
partitions are smaller, it will take some care to keep the sanding even.

19. Repeat step 18 on the other side of the comb. [If you are not removing the
original Hohner finish, skip now to step 26 and start your wax dipping.]

20. Repeat step 14 (lightly sanding the front edge of the comb) with 600
paper. The goal in this step is to gently remove any remnants of factory
finish from the front edge, and any marks from the 400 grit. As with any
gradient sanding, the idea is to remove as LITTLE wood as possible, just
taking out the marks from the previous grit, as it woud be very easy to create
an unacceptable tolerance between the front edges of the comb and plates.

21. Repeat step 20 with the 1200 paper. Gentle, gentle.

22. Repeat step 20 with 1500 paper.

23. Repeat step 20 with no paper, polishing the front edge of the comb on the
smooth marble (make sure the marble is clean so as to not mark the comb with
soil). You should notice the front edge taking on a bit of a shine. This step
is to make the surface very smooth, and crush the open wood cells, which would
create and undesirable drag and sensation on the tongue.

24. Since, some material has been removed, however slight, from the the
thickness of the comb, now is a good time to do a test assembly of the harp.
Assemble the harp with screws and check that the plates are seating properly
by looking through the chambers toward a bright light. If you see light coming
through between plate and comb, it likely means that the rivets on the draw
plate are hitting the comb. (You will usually find that the draw plate is the
problem.) If this is the case, using a punch, lightly tap down the semi-
circle-shaped areas that have been pressed in to accept the rivets from the
draw plate on the underside of the comb. This step is to deepen that
receptical so the plate seats better. I use the flat head punch from the
Farrel Reed Knockout Kit. Be very careful, and go slow, as it is easy to just
chip this area right off the comb. That may not be a disaster, unless you
compromise the general integrity of the comb. It is also possible that the
plates are not seating if the comb is uneven from manufacture, or from
improper sanding, or if you have not removed all the excess wax. Another
possibility is that the combs on used harps may be warped from exposure to
moisture during play.

25. Dissemble lean the comb with a lint-free cloth.

26. Heat the beeswax on warm-to-low heat. I just put the block of wax into the
pan, and use it to stir the liquid wax as it is melting. I remove the block
after I have about 3/8 to 1/2 inch of wax melted. Do not overheat. Use a
thermometer to watch for the temperature at which the beeswax melts. Don't let
the wax get more than 5-10 degree F over that point. Enjoy the honey-sweet
smell!

27. Firmly, push 3 toothpicks into holes you have drilled in the comb for the
screws.

28. Lower the comb by the toothpicks into the melted wax. Let the comb stay in
the wax for about a few seconds, stirring the comb around in the wax, and not
letting the comb lay against the bottom of the pan, where contact with the
burner could overheat the wood. It is important to have the wax at temperature
that is not so hot as to be damaging to the wood, and not so low as to not
provide for good absorption into the wood. This is something to experiment
with, and I suggest a very low stove temperature. CAUTION: Wax will burn the
skin even at these low temperatures.

29. Lift the comb out of the wax and hold it in a position where the
partitions are facing up, letting the wax drip back into the pan as it dries.
One or more of the toothpicks may have a tendency to fall out, so you'll be
glad you have used three.

30. After the wood is cooled a bit and the wax is solid and yellow where it
has accumulated, repeat step 28. You may wish to dip it a third time. Each
time you redip the comb, it will become warmer. If you observe air bubbles
coming from the wood, the wood is giving of moisture. This is a sign that the
wood is getting to hot, and should be kept to a minimum, although you need to
have the comb near to this temperature to get good wax penetration.

31. When wood is cooled again to the point that the larger accumulations of
wax are yellow, begin to remove the excess, using the feeler guage or some
other dull edged metal strip, to scrape the surfaces down flat and smooth. Do
this step while the wax is still warm, and and workable. It's very important
to not leave any high or uneven areas of wax, being sure to also remove wax
from the sides of the partitions. Be meticulous here. You are preparing the
joint between plate and comb. If you have let the hot wax drip with the
partitions facing up, most of the excess wax will be at the bottom of the comb
and on the top edge of the partitions, making the removal fairly easy. Use a
small tool to remove and excess from the withing the partition channels and
the semi-circle-shaped areas that are milled to accept the rivets from the
draw plate on the underside of the comb.

32. Check plates and use the file or countersink to remove any burrs created
in drilling. You may wish to clean up the plates and covers if you are working
an old harp.

33. Assemble the harp.

34. Gently but rapidly polish the front edge with the soft, lint-free cloth.
The heat of light friction softens the thin surface wax and smooths out any
irregularities.

You may wish to roll in the back edge of the covers, a la Joe Filisko.

Beeswaxed finishes will eventually deteriorate, especially along the leading
edge that is in contact with the mouth, and most especially if a lot of tongue
block playing is done that puts friction on the soft wax surface as it is
being digested by the saliva. This can take a few weeks to a few months. Also,
reapeatedly dissembling the instrument to clean or tune it can violate the
integrity of the wax gasketing between plate and comb, as the wax has a
tendency to stick to the plates and be pulled from the comb. At any point that
you feel the wax sealing and protection, or gasket losing its integrity, you
can just take a few minutes to redip your comb in wax, restoring it to its
former ideal state.

Please bear in mind that this is just one way to approach it, and you may find
easier and quicker methods. So, just take this as a jumping off point if you
like.

It may seem like a lot to do, but it's not once you get the hang of it. It's
quite fun. And if don't have time to mess with it, you can order beeswaxed MBs
from Master Tim Moyer. (And hopefully, soon, from me. :)

- -Dave Therault