Building Tips and Techniques

by Craig Landrum

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I cut my pipes from basswood with maple languids and cherry caps, with cedar and chamois stoppers. I cut all of my pipe parts on a microLux saw available from www.micromark.com. With the fine blade, this saw generates glass-smooth cuts which practically eliminated sanding of the pipe parts. To create the sloped cap (which I cut at 15 degrees), I simply cut a 15 degree wedge and clamped it to my sander. I then sanded the wedge, then cut the lip to length. Note that the modellers saw mentioned above is not suitable for cutting 1/4 ply for other organ parts, as it will tend to wander.

I had a problem finding correct diameter tube for the takeup spool until a friend recommended I look at some large scale model rocket sites. I found a 2.5 ID tube with .060 wall at www.publicmissiles.com. Click on their Webstore and then Airframes. The "Quantum" tube is grey plastic and cuts nicely on the bandsaw. Worked great, and I was easily able to use a hole saw to cut out some 2.5 inch wood plugs for the middle area (where the roll hook goes) and the spool ends (to which I attached 1/6" aluminum disks, cut from flat sheet stock using a fly cutter on the drill press).

Instead of leather washers used as spacers/sealers on the inside axle of the takeup spool, I used 1/4 solid brass rod for the axle with exactly fitted 9/32" brass tubing for spacers and brass washers where the spacers met the side of the box. This was easier to fit than it sounds, kept the box reasonably airtight, and made the takeup spool rock solid with no side slip. Don't be shy about trying some brass work - brass cuts easily on bandsaws, with the modeling saw I mentioned above, or with an Xacto saw. In any case brass tube (which can be obtained in small quantities from www.micromark.com), makes the project look and feel great. I also used 1/4" and 5/16" tubing for all tracker bar and pipe connections.

Instead of wood clips on the outside takeup spool drive wheel, I epoxied a 1/4" steel shaft collar with a set screw to the drive wheel. This made the drive wheel easily adjustable, nicely centered, and solid on the axle. I obtained the 1/4" shaft collars with set screws from my local ACE hardware, which is also where I obtained all of my brass screws for the project.

I drilled out a small block of cedar and made a holder for a Singer sewing machine precision oiler. This is a nice oiler since it has a internal tube that can be extended for hard-to-reach places. I attached the holder to the inside of the case in the crank area (see pic).

I created a rewind handle that works with the hex-end rolls (and use John Smith's roll support dimensions in the plans). I used a small length of cherry, a few lengths of 1/4" wooden dowels, and some 9/32" brass tubing to fit over the dowels. I epoxied a cut-off section of a cheap hex wrench into one brass tube and turned a small free-spinning handle on a mini lathe. I carved some supports for the small rewind handle so it can also reside in the crankshaft area (see pic). I epoxied a couple of small magnets near the ends of the crankshaft area door and also in the crank area - this gives the door gentle but positive closure without needing latches, etc. A couple of strips of adhesive-backed red felt made the area look nice and let the door close softly.

I used 3/4" and 1/4" solid brass rod to craft the crank handle. I'd never done brasswork before, but it was relatively easy to drill the holes and use a cheap tap and die set to fit the parts and also thread the end for a nut to hold the lathe-turned handle. I also threaded the end of the crankshaft so the handle simply screws on to the shaft. This worked well. I cheated and bought a crank from rollcutters.com, and it was quality work, although it was 6mm instead of 1/4", but this made little difference. I got the 3/4" and 1/4" solid brass rod I used to make the crank as well as the 1/16" aluminum plate I used to make the takeup spool ends from www.onlinemetals.com. They will cut down to as little as 1 foot length and 1 foot square sizes. The brass can be cut on the bandsaw, drilled on a wood drill press, and taps nicely. Be sure to get some "cutting oil" and use it liberally when drilling or tapping. As a threading novice, I have no idea what is standard practice, but I found that it is easy to start the threads if you use your rotary sander to create about a 1/4" long taper in the end of the rod into which you will be cutting the threads. When cutting threads or tapping, use a technique of advancing about 1/4 to 1/2 turn, backing off, then advancing again, being sure to clear metal chips away with a throwaway brush every so often - and don't forget that cutting oil! After final assembly on the handle, I cheated and fed a few drops of superglue into the joint where the 1/4" handle rod screwed into the 3/4" crank body so things would stay tightly in place.

I made the lid clip out of cherry, but with a brass top - I didn't like the idea of wood moving against wood. I also added a strip of brass to the lid where the clip rests. Strip and sheet brass is available from www.micromark.com. Thickness isn't critical.

Using player piano motor cloth on the bellows worked fine with card stiffeners glued on. My main problem was weakening the spring enough to stay at 6" of pressure, which it would hold for 15 seconds or so. I obtained all my organ cloth and the traditional hide glue used to attach it from www.player-care.com - service was fast and friendly. The type of cloth I used was what John Tuttle sells as "Peripheral Device Cloth type A" which is wine-colored and looks great. I also recommend using neoprene tubing instead of the clear aquarium tubing. You can also get the tubing from the player-care website. I got the No.8 1/4 ID tubing for the majority of the pipes, No.10 5/16" ID tubing for the lowest 5 bass pipes, and No.19 3/4" ID tubing for the connection between the reservoir and the pressure box.

On a tip from a fellow builder, I used 1/8" ply with recessed T-nuts glued to the back of the pipes - this made it easy to mount the pipes to the board. The technique involves using a 1/2" forstner to drill a 1/16" depression in the 1/8" ply, followed by drilling a 1/4" hole through the center of the depression. The T-nut is then hammered flat into the depression and the ply is the glued to be back of the pipe. A single hole in the mounting board allows the pipe to be easily bolted to the board. Clean and solid, and it avoids screwing anything into the actual pipe. By the way, I mounted my pipes about a half inch lower than the plans - the top of my center pipe is about 1 inch from the top of the backboard. I used the same T-nut technique to mount the mitred bass pipes to the side of the case in the back. I epoxied on a 1/4 piece of ply near the feed tube for the two back bass pipes and used a 1/2" screw through the side of the pressure box tracker area to hold them in place at the top. Unlike some reports, I didn't have a great deal of trouble attaching the final air feed hose to the F pipe feed tube - by cutting the semi-stiff rubber hose to the exact length and by moistening the feed tube on the pipe, I was just able to position the feed tube over the end of the rubber. When slid into position, the rubber hose then slipped (unseen) the rest of the way onto the pipe tubing, which I then verified by playing the note.

I did the initial voicing and tuning of my pipes before attaching them to the organ. I used a simple inexpensive chromatic tuner.  You simply play the pipe and the tuner displays the note and whether it is flat or sharp, etc. One lesson I learned the hard way - be absolutely sure you don't mess with the calibration (or let your kids mess with it!) as you will end up voicing and tuning your pipes too long or short. I simply made sure that the tuner was set to its default setting of 440hz for 'A' before I started and everything was fine. I did a final tuning after the organ was assembled. By the way, like several other builders, I found it necessary to add the "wings" onto the lowest bass pipes inside the organ. It's needed for the C pipe so it will fit without interfering with the drive wheel, and it's needed for the B flat and F pipes so they will fit into the available space in the back. I did all my pipe mitring using a standard Black & Decker power mitre saw, being very careful to allow about 1/8" space between the pipe and the side of the organ to allow for eventual mounting hardware (I used the 1/8" ply and T-nut technique to hold them in place and provide support).

I finished the case with black gloss enamel with several clear topcoats. I used brass finishing washers which set off the screws in the side that hold the box, bellows, etc.  The front was detailed using cheap gold Testors enamel and a few water-based decals. If you try decals, avoid the mistake I made of picking decals on a white background that will eventually go on a black surface - the subtle colors that show well against white almost disappear against black. Next time I'll pick decals that are designed to be used on dark surfaces. After the gold and decals, I added a clear topcoat to finish, which I recommend spraying to avoid dissolving and smearing the gold.

I have many other pictures of the construction process and will be happy to email selected ones to anyone that needs them.

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