Woodturning a Round Train Whistle


Uploaded by AsWoodTurns on 11.01.2013

Transcript:
Hi, Alan Stratton from As Wood Turns dot com. A bit ago, Steve Ramsey on his channel had
a video on how to make a train whistle. He made it out of a square piece of wood.
But, to me, there's a problem with that. The world, as Columbus discovered, is not
flat. The world is not square. The world is round. A train whistle, in the woodturning
world, needs to be round. Let's make a Round train whistle.
I started with a piece of poplar about 6" long and 2" square. The first order of business
was to layout the holes to drill for the air chambers. I drew up the layout in Powerpoint
and transferred it to the end of my poplar. Next time, I would print out the diagram at
full scale and glue it to the wood. That would save the layout hassle at this small scale.
I marked the center of each hole and the center of the block with a punch. The punch helps
a lot to guide the drill to the right point. Metal workers use these all the time -- I've
found them very useful in drilling wood. I drilled all four holes as deep as I could
on the drill press. This limit was due to the quill travel -- not the length of my
drill bit. It helps a lot to clamp the block with a large wood clamp. The trick here is
to have the clamp handle press against the drill press column. This prevents the block
from rotating. I marked the desired hole depths on a side
of the block and used this to set the depth stop on the drill press. Instead of drilling
out the remaining depth with a hand drill like Steve did, I used scrap plywood to elevate
the block to eke out enough drill press capacity to drill to the desired depth. The trick is
to insert the drill bit into the hole with the power off. Then lift the block and slide
the plywood under the block. I used a brad point bit that had some roughness higher up
on the side. This may have contributed to reaming out the hole at the top. Next time,
I would use a forstner bit that would tend to drill straighter and has no shaft to ream
out the hole when going deep. Turning the whistle body is mostly very straight
forward. I turned it round then used sandpaper glued to a piece of plywood to ensure the
body is perfectly straight. I know of no reason that requires the opening
to be square. I did not want to saw it out -- I wanted to turn the openings. I marked
the top edge of the opening at 5/8" down from the top.
Starting with a gouge I roughed out the opening then refined it with a skew. The poplar turned
out to be very stringy. I used sandpaper wrapped around a dowel to sand the interior of the
chamber. I may try poplar again but see if a forstner bit would produce a smooth bore.
If that does not work, then I'd eliminate poplar for whistle bodies.
I also turned a small tenon on each end of the block to use to attach end pieces.
For what I call reeds, I used standard hardware store dowels. However, these are rarely even
close to proper size. This one was undersize. An undersized dowel coupled with holes that
were reamed out by my drill combined to produce a very loose fit. This made it difficult to
fit and tune the reeds. I sanded a flat as required on the side of the dowel, cut it
oversize, and glued the pieces into the chamber hole. The critical points are the right amount
of flatness, to align the end of the dowel to the top of the opening and to have the
flat aligned to the outside of the opening. Fortunately, you can test the reed before
gluing it in place. When all is done, then trim all the dowels back to the top of the
whistle body. I found a piece of walnut for the end caps,
rough turned it, turned a tenon on the end for mounting in a chuck, turned a tenon in
the middle for the other end cap, then with a parting tool cut it almost clear thru. Parting
a spindle in half while between centers is dangerous if you go all the way because then
the two pieces can bind and do all sorts of strange and dangerous results. On my piece,
I may have pushed it a little too far because the remaining column of wood was very thin.
I was able to separate the two pieces by twisting them apart. Too close for comfort, I should
have had to use a saw. The first end cap was for the bottom. Essentially,
the end cap consists of a small recess to receive the tenon on the whistle body and
a finial. I started by hollowing the end for the tenon and fitting it to the whistle. I
had expected to then flip the wood around and remount the wood on the long neck jaws
for the chuck. This mount would have the jaws expand into the recess.
However, after changing the jaws and mounting the wood to the recess, I found the jaws were
just a little too big for the recess. I have no smaller jaws. I quickly considered making
a jam chuck. Since I had not yet separated it from its first tenon, I decided to put
it back the way it was and just finish turning it from the original mount. The difficulty
was the finial, Holding a finial from its pointed end is a bit tricky -- any significant
pressure when the stock is very thin could result in a broken tenon.
With this in mind, I finished the end cap a little by little. First, from the recess
around to the base of the finial. I turned it, sanded it, and finished it. The finish
is the mineral oil and beeswax mixture I also use for sanding. It's especially nice here
because there is no problem blending it into previously finished areas. I wanted a very
minimal finial anyway. Then on to the main portion of the finial -- again sand and finish
it before getting to the final portion that would only be about 1/8" in diameter. Even
this area, I sanded and finished the wood. Finally I parted it off. To sand the last
little bit, I put the sandpaper flat on the lathe bed and rubbed the point of the finial
on the sandpaper. A little more wax and it was done.
The top finial was similar except I already knew it would not fit on the jaws. The differences
are the mouthpiece and a small air chamber so that each sound chamber has an air supply.
So after a preliminary hollowing for the recess, I drilled the hole for the mouthpiece. For
this I used a handheld drill. Unfortunately, the drill bit spun in the handle and cut my
thumb. I need to epoxy the bit again into the handle before using it again. You may
notice the bandage appearing on my thumb. I hate getting blood on my projects, especially
my blood. I hollowed it a little more for the distribution
chamber, then turned my focus to the exterior, following the same process as for the bottom
cap. Turn a little, finish, turn a little more, and finish it, and so on. The main difference
was that I had to allow for the air hole down the middle. The mouthpiece is almost too thin.
The fun part here of using the skew here is to create these little rings of wood as you
peel off the end grain. They don't last for long. But it's kind of fun.
There are a lot of variables interacting on this whistle. I wish I understood all of them
so I could improve the result. Some of them are: air chamber depth, air chamber diameter,
opening size, how hard I can blow, the wood resonance, the size and placement of the flat
on the reed dowel. Probably even the temperature and humidity. I know the chamber depth and
diameter determine most of the resulting pitch, but there's a lot more going on here. If
there is someone out there who knows about this stuff, please comment below. My wife's
cousin makes large pipe organs, I may have to pay him a visit.
So, here we are with a "Round" train whistle. Toot Toot.
Please like this video and subscribe to my As Wood Turns channel. There's also more
at my website, As Wood Turns dot com. Thanks for watching. We'll see you on the
next video.