Hammer dulcimer, Part 4

Ok folks, last round of pictures.

Here’s the soundboard, with the piezo pickups glued to the underside and wires soldered to them:


And here the wires are threaded through the holes in the braces.  When the sound board is lowered into place, the wires are pulled somewhat taut, so they won’t rattle around too much.


Now the wires are pulled out through the jacks hole, and trimmed to length:


Then the ends are stripped, and the hot wires are all soldered together, and so are the ground wires, with a short section of wire that will go to the jack:


The soldered portions are trimmed down, and covered with tape so they won’t short out:


Now the wires are soldered to the jack.  After taking this picture, I realized I got the hot and ground wires mixed up, so I had to reverse them…


Now the jack plate is screwed to the instrument:


Here’s where those steel rods end up.  The idea here is, after stringing it up, you can move these rods around if it doesn’t sound good.  You have to do it fairly quickly, because the string pressure will make press the rods into the soundboard a bit, and it they won’t want to move then.


The bridges and saddle set into place:


Here’s the delrin markers that go on top of the bridges.  White ones mark the start and end of keys:


I almost forgot my label…


Here it is with half the strings put on:


The other half:


And it’s finished!  Please excuse the cluttered desk…


I’ll try to record a video or sound clip soon.

If anyone has any questions, please don’t hesitate to speak up.




Hammer dulcimer, Part 3

Here’s the last shot of the sound board, after squeezing the rosettes in:


Time to make the bridges.  First thing is to determine the space between holes.  This is usually the most frustrating part of the whole deal.  But this time it was a cinch, so maybe my frontal lobe has developed some since I last made one of these.  😉

This time, I stretched a thread between the pins, at the top and bottom of the blocks, then measured the distance between them, at the position and angle where the bridge will be.  Then divide that number by the number of spaces between courses.  So, for the treble side, it was 19.125″, divided by 17, = 1.125″.


So, having got that figured out, it’s time to process the wood.  I used curly maple for the bridges.  First cut it out of the parent board, then joint the edges, and plane to 5/8″ thick.  I’m making these 1-1/8″ tall.


Now the table saw is used to make a V shaped groove on the top:



Then the holes are layed out:


and drilled.  I used a 3/4″ forstner bit.   I also marked where I’ll be cutting notches:


The notches cut and the bridges set in place:



Here’s how the cross section of the bridges ended up:


I’m using 3/16″ diameter music wire set on top of the braces, to support the bridges.  I was worried they wouldn’t be strong enough to support it, so I added some braces in between the others:


Now it’s time to make the strips of wood that hold the saddles.  They’re made pretty much like the bridges, except they’re only 1/4″ tall:




Now it’s time to drill out the tuning pin holes:


The pins:


I made this tool for driving the pins in.  It keeps them from going in too far.



The hitch pins:


Making a carrying handle:




The hole to the left of the handle is for the pickup jack.

To be continued… again…

Hammer dulcimer, Part 2

The sound board.  I’m using some western red cedar that I got from a lumber yard here in town.  It started out as an 8″X8″ fence post.  I cut it down to 48″ long, wasting some knots in the process:



Then I ran it through my planer to clean it up:



I normally use my 14″ bandsaw to resaw this sort of thing, but I don’t have any sharp blades for it right now, so I used the table saw.  Was not fun, but it did the job.  Had to cut from both sides, of course.  I cut it plenty thick, and then planed the pieces down to 1/4″ thick.

I guess I neglected to get any pictures of the raw cut pieces, but here are some of gluing them all together.  The short piece at the top is some old cedar or redwood the a friend gave me.  (Yo, Chris!)  He said it was salvaged from a river bottom after being sunk for 150 years.  After smelling it, I believe him.  😀





After gluing all 4 pieces together, I mark it to cut it to it’s final shape:



Then cut it so it fits inside the body:





Now the locations of the soundholes are determined, and pilot holes are drilled.  I also made the grooves at the locations of the bridge braces, which will be used for adjusting said braces:






The rosettes.  Turns out they weren’t glued in to the old HD, so they just popped out.  That was nice.  🙂



I used a hole saw so cut the sound holes:



And this is why I hate hole saws:



It’s also why I drilled from the bottom of the soundboard.  So no one will see mistakes like that.  😀

After the holes are drilled, the side edges have a bevel planed on to them, which will hold the saddles, then the top is sanded smooth, and a coat of sealer is applied:




After the sealer is dry, the soundboard is sprayed with a few coats of black lacquer.  Here’s the first coat:




When the first coat is dry, some dirt is removed, and other defects sanded, then a couple more coats are sprayed.  Here’s the last coat of black:



Then several coats of clear go on.

To be continued…




Building a hammer dulcimer, part 1

Hey all,

I’m still going to do that news post I mentioned before, but in the meantime here’s another “build” post.

There’s a little bit of a story behind this one.  A couple years ago, my brother and his fiance went down to a southern state, and I knew that some of the people they were going to see were musically inclined, so I sent this HD (hammer dulcimer) down with them, so they could give it away.

Well, there were a couple things about it that in retrospect I wanted to change, and I was able to get it back from it’s owner recently.  When I did, I discovered it had more problems than I had realized, so I got permission to replace it.  So, here’s the old one:


Actually, it’s ashes now, but this is what it looked like just before going into the woodstove.

I salvaged the hitch and tuning pins, and I’ll be using them on the replacement. The main things that were wrong with it were, that I used Titebond 2 in assembling it, and the top was several inches too wide.  Titebond 2 creeps, and the string tension on a HD can be as much as 2 tons.  So the joints were slipping, and it wouldn’t hold a tune…

So, on to the project.  The old one had a plywood top and back, and also baltic birch plywood braces.  The new one will have a plywood back, but a cedar top, so the tone will be much better.  It will have maple braces and pin blocks, and mahogany trim.

The first step is to cut the back out, and then draw the locations of the pin blocks and braces on it (it’s upside down here):


Then make the pin blocks.  It’s important to use hard maple (also called rock, and sugar maple) for this.  Anything softer will not grip the pins, and your instrument won’t hold a tune.  I used baltic birch plywood once, and it didn’t work.  We’ll leave it at that…

Osage orange would probably work too, but maple is so cheap and plentiful, and much easier to work with.  Mine grew a few miles away from my home.https://i0.wp.com/www.pattonblades.com/120212-2.jpg
I cut out four pieces:


Then planed them clean and flat.  Here they’ve had two holes drilled for dowels to keep them lined up when gluing, and the glue has been applied:


Then apply clamps and leave overnight:


Next a ledge is cut on what will be the inside edge of the blocks.  The edges of the free floating sound board will rest on these ledges.  I used the table saw for this step.


Now the pin blocks are set on the back, and the positions of the braces are marked:


Then the notches for the braces are cut, again using the table saw.


Then the top is cut at an angle, again using the table saw.  In the past, I’d used the band saw, but the table saw was so much nicer for this step.


Now the pin hole pattern is taped to the angled surface, and the pin holes are marked with an awl:


Then the holes are pre-drilled with a 1/8″ drill bit.  My drill press doesn’t have a tilting table, so I have to use a jig in the vise to tilt the pin blocks so the surface is horizontal:


Now the pin blocks are glued to the back.  Since the top is now slanted I use the offcuts as a clamping caul, like so:


The nails are to keep the cauls from sliding “downhill”.Both of them done:


Now the braces are made.  First, they’re cut to width (slightly lower than the ledge) then to length, using a miter saw:


Then a bunch of holes are drilled, so that the inside will act as one sound chamber, rather than three small ones.


Now the braces are glued in:


And some mahogany “cleats” are glued on to the outside braces, to give the trim boards something to glue to:


Then the top and bottom edges are jointed, so they will be straight and flat.Now the mahogany trim pieces are cut to length and width, then planed down to 1/2″ thick:


and then glued on:



Now the extra wood is removed with chisel and plane, and then the surfaces are sanded and prepped for spraying:







The sharp corners are cut off, to make it less painful when run into:



and the edges are all sanded round:



Then it’s vacuumed out, and gone over with a tack cloth.  Then it’s time for spraying.  Here’s the gun:



Here’s the victim:



After spraying:



I decided to leave all the woods natural, except the soundboard, which will be sprayed with black lacquer.

To be continued…