The Bagpipe Project - Tenor Drone

Lower Section
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The basic steps include center boring, roughing the cylinder, cutting primary diameters, making and attaching projecting mount blanks, and final profile turning. This page details these steps.

Turning blanks start out square in section. In traditional turning, the square is initially rounded with a roughing gouge. One end of the blank is centered and held in a 4-jaw chuck while the other is held in a live center. Since I'm using a metal lathe with power feed, I can take a very deep cut from the end grain, and round the blank faster and much more easily than with a gouge. It's a lot less messy too without all those little chips flying around and getting under my t-shirt!

This initial cut creates a smooth surface for the follow rest to ride on. The follow rest attaches to the lathe apron and will support the stock for center boring. The other end of the blank will remain chucked in the 4-jaw chuck during the center boring process.

This shows the stock in the steady rest with the initial pilot drill. This will start a hole that acts as a bushing to guide the gundrill.

Here is the follow rest positioned on the stock and a roller bearing held in the tool changer. The follow rest touches the stock on the top and back side. The roller bearing is on the front and below center to make the third contact point. A little oil on the wood is all it needs to run smooth and cool. A pilot hole is drilled in the end of the stock and acts as a starting bushing to guide the gundrill.

This is the same shot showing the compressed air valve and fitting attached to the gundrill driver and all ready to go.

The gundrill is held in the tail stock of the lathe with a Morse taper. The stock spins driven by the 4-jaw chuck and the tail stock is pushed forward into the stock on the bed of the lathe.

This shows the gundrill almost all the way through. This 5/16" diameter drill bores through the blackwood in less than a minute. Compressed air is used to clear the chips from the hole as the drill moves through the stock. Spinning the stock instead of the drill helps keep the drill aligned with the center of rotation.

Next, the blank is rechucked on the center hole using a mandrel in the self-centering 3-jaw chuck. From this point on, everything is centered based on the bore location. That's why it is done first. It wouldn't do to have the center bore off-center now would it?

This shot shows the roughing pass almost finished. See the ribbon of blackwood going up into the dust collector hose? Sharp carbide tools are a must. Blackwood has a severe dulling effect on tools.

Next, general sizing cuts are made to establish basic diameters of the drone section. There are five: Reed seat boss, internal mount shoulder, tone chamber, another mount shoulder, and the pin.

This cut shows the internal mount shoulder on the reed seat boss end. the reed seat boss is only 1/32" smaller.

This shot shows the sizing pass on the pin end of the drone section. This diameter is the shoulder for the projecting imitation ivory mount. This cut will go all the way to the pencil line to the left.

After this the actual pin diameter is cut in a single pass.

Projecting Mounts

Here you can see a blank of imitation ivory held in the 3-jaw self-centering chuck. The tail stock is now holding a drill chuck with a center drill. The center drill establishes the center of the stock for later drilling or centering operations.

This shot shows the center drilled hole. The center drill has been replaced with a twist drill the same size as the finished pin. This will drill the small diameter needed inside the mount.

Now I have changed the drill to a 7/8" diameter bit. This is the larger diameter for the shoulder in the mount towards the tone chamber. It will only go part of the way through the mount blank.

Here is have changed the drill chuck with a live center. The live center holds the drilled end of the stock. I am driving a cutoff blade into the side of the stock to trim off a projecting mount blank.

The cutoff tool isn't quite long enough to cut all the way through the 2" ivory rod. Here I am using a dovetail saw to complete the cut.

I need two of these mount blanks for the lower tenor drone section. They are the same except for the smaller diameter hole. One is the diameter of the pin and the other is the diameter of the reed seat boss.

Now it's beginning to look a little like a drone section don't you think? Here I'm clamping the mount blanks to the blackwood. I'm using epoxy to join them together.

The final shaping of the drone and mounts is done together.

I have remounted the drone section back on the lathe and I'm rough shaping the mount on the pin end to rough shape.

Here I am rough profiling the other side of the same mount.

This view also shows the depth groove that I'll shape the center section down to. this groove is cut with a hand held parting tool.

After rough profiling, I replace the indexing tool post with a piece of angle iron attached to the apron much like the tool rest on a wood lathe. Then I use small scrapers to do the beading and smooth to the final shape. Notice how the area shaped with hand held scrapers is not as smooth as those cut with carbide cutters.

Now I have finished the beading and combing and moved the drone section to the wood lathe for sanding. The wood lathe spins much faster than the metal lathe. I sand through a schedule ending with 600 grit. After sanding I use automotive polishing compound to gloss up the blackwood and the ivory mounts. After that I spin on a thin coat of tung oil. This shot was taken just after applying the oil.