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Setting the Drive Ratio
The drive ratio between the crankshaft and the take-up spool must be adjusted
so that the bellows are working fast enough to supply enough wind during
the heaviest parts of the music. The wind supply can be increased by
reducing the size of the drive wheel, or by increasing the
size of the take-up wheel. Both of these adjustments slow the music
speed down and therefore allow the crankshaft to be turned faster.
The diameter of the idler wheel makes no difference. When
setting the drive ratio, always remember to test it at the end of
a long music roll, not at the start. This is where the music speed
is at its fastest and the crankshaft speed is at its slowest.
Melvyn Wright |
Detachable Crank
It helps assembly and future maintenance if you make the single crank detachable
from the end of the crankshaft. This makes it possible to slide the
crankshaft in and out without removing the bearings, and to easily remove
the drive wheel, connecting rod, etc. It is also easier to make, especially
if you don't do welding! The crank can be secured to the crankshaft
by a single set screw, which grips the crankshaft. A flat should be
filed on the end of the crankshaft to prevent the crank from slipping round,
and to ensure that it is mounted exactly 180 degrees from the main crank.
Melvyn Wright |
Positioning the Bellows Spring
An easy way to position the bellows spring is to use a shower curtain clamp
to hold it in a compressed state when it is placed inside the organ. After
the spring is in place, the clamp is either rotated or opened slowly so that
the spring stays in place and the clamp can be removed.
Galen Lesher
Rubber or Neoprene Tubing
I suggest using rubber or neoprene tubing on the organs, as this is more
pliable than plastic, and lasts longer.
Some suppliers of tubing and cloth:
Cambridge Pianola
Company, The Limes, Landbeach, Cambridge. CB4 4DR. (UK)
Player Piano Co.
Inc., 704 East Douglas Avenue, Wichita, Kansas 67202. U.S.A.
P. Turner |
Measuring the Porosity of Wood and MDF,
etc.
I have had to rebuild my bellows and reservoir and I wanted to properly seal
the MDF. I have recently bought a Sat Nav, and this has a suction pad
to hold it onto the windscreen. I thought that this could be utilised
to give me a good test of the various sealers that can be used to seal the
MDF. Comparing 'raw' MDF with sealed showed that the paint I used for
the sealer did its job - it showed a huge difference. It looks to be a quick
and easy test. Marcus Foreman |
Clearing out Paper Dust and Debris
The design of the Busker Organ makes it susceptible to blockages in the tubes
and pipework caused by paper dust. Because the air is blown through
the music and straight into the pipes, paper dust could eventually block
the narrow windways in the pipes. But this same design also makes it
very easy to clean them out. This can be done by sucking out the tubes
with a small vacuum cleaner. Just open the pressure box lid and apply
the vacuum cleaner nozzle to the tracker bar holes. This will clear
out all the debris in the tubing and the pipework, and also in the tracker
bar itself. That's the entire pneumatic system cleaned out in just
a few seconds! If your tubing is made from transparent plastic, you
will be able to see all the internal dust disappear in a flash. If
you put the vacuum cleaner on Blow instead of Suck you might even get a tune
out of it! Warning: Do not try this on organs with a valve
action (such as the JS Universal) as the vacuum force could be strong
enough to damage the valves. Melvyn
Wright |
Hoover Belt
When you get the Hoover drive belt, you will probably find that it has got
a moulding flash all around the outside, just where you don't want it (and
probably the inside as well). I found this was causing intermittent
slipping when under load. Put the belt on the idler wheel as normal,
and then twist it through 90 degrees, so that the flashings appear on the
sides instead of on the periphery. This gives a much smoother driving
surface. Melvyn Wright |
Sanding Block
If you put medium sandpaper on one side of your sanding block, and coarse
sandpaper on the other side; not only does this give you a choice of two,
but it prevents the block from sliding about on the bench, so you can use
both hands to hold the workpiece. Don't use it on the dining room table
though! Melvyn Wright |
Pipe Stoppers
When making the pipe stoppers, don't try to cut out the leather first. The
job becomes much easier if you glue the bottom of the stopper to the
sheet of leather first, wait a few minutes for it to dry (you can be sanding
the inside of the pipe at this juncture) and then cut out the leather around
the stopper, leaving the appropriate margin of course. I just used
1/2" brass wood screws for the stopper handles, and 1" screws for the bass
pipes. These disappear inside the pipes and are not seen. They
can even be removed after tuning, if
required. Melvyn Wright |
Alternative Take-Up Spool
One problem that us builders in the U.S. have is obtaining the 68mm tubing
to build the take-up spool. Others have written about their solutions. My
solution came as I was taking out our recycle bin to be picked up. I
noticed a plastic container that looked like it might be close to the right
size. To my amazement, it measured 67mm in diameter. Problem solved. The
product can be found in most grocery stores. It's Crystal Light Tea. It contains
six small tubs to make two gallons each of the tea. Hope this will be of
help to those builders in the U.S. or those that can find the Crystal Light.
Harold M. Whipps Sr |
Music Roll Bias Spring
I do see quite a few good ideas from builders of my organs, these are usually
because the particular builder can get hold of a certain alternate material
for the job. Often this is not something that is readily available or needs
special skills to make. However every so often something really useful comes
along that can be freely obtained by anyone. I can recommend this one: If
you disasemble an old VHS tape you will find a leaf spring that is perfect
for the music roll bias spring, it even has the fixing holes ready drilled.
John Smith
(Bias spring warning) |
Old Sewing Machines
If you should happen to desire to build your organ with precision, machined
bearings/bushes, shafts, bosses, springs etc then a visit to your local sewing
machine shop may prove rewarding. It is common for repairers to have accumulated
machines which they really intend to discard - eventually. Usually the
shopkeeper/repairer is only too happy to have you dispose of the obsolete
items saving them the bother. All it takes is a little time to dismantle
the machines remembering to remove all bushes from their precast housings.
Take care not to throw these "babies out with the bath water". An additional
benefit maybe the additional supply of cams, cranks, various gears and other
"natty" machinery bits and pieces - "far too numerous to mention".
Ian Hemingway (Australia) |
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