Fingerboard Shaping

Whenever people talk about shaping a fingerboard they invariably mention the specific block plane that they like to use. I haven't found one. My tool of choice is a scraper; more specifically an old plane blade.

To make a fingerboard I cut the wedge first from a 2" X 2" block of ebony a foot long. You can figure out how high each end should be by using some geometry and a calculator. It comes out to about 8 mm at the top and about 11.5 mm at the bottom. That is with a 5.5 mm edge, and a 42 mm radius, and a little extra. I cut it wide of the line and plane both sides flat; with my big jointer plane. Then I cut the edges; that is straightforward enough; and plane them straight.

The only step you need to carve the top is a pencil line on the sides 5-5.5 mm up from the bottom. Hold the blank in your left hand, and with your right hand start planing off big slivers of wood off with the scraper. Hold the scraper at an angle to the blank, and move it generally in a straight line, concentrating on getting it to the scribed line. Ever once in a while check with your fingers to see if the top curve seems right, and that there are no high spots. If there are smooth them out with your angled scraper.

Use a straight edge to see if the middle has some undercut in it, a little more on the bass side. I have to be sure the ends aren't high or low; I've managed to get them both ways, so now I leave the ends long, and saw it to length when it is roughed close to size.

In an hour you will be done.

The blank is now still a blank. I won't finish it until I can work out the projection. That way if I have to keep it thick I can, and if it can go thinner, or needs to be moved around some I have a mm or so leeway on each end for tipping. That is the time you can work on getting the relief just right, the edges even, and that sort of thing.

Try a scraper, it is easy.

Color under the ground

The other day before starting to glue (I"m still at it, I've been busy) I sealed the wood with some resin in alcohol, and tried to color it a green/gold. I used a tiny bit of Azo Green on a toothpick, and some tannin in alcohol and tried to point it until it was even. Originally the back is quite white, and the belly is quite red.

Now they are closer to the same color, and it does have the green/gold look I was going for. It seemed a little bright at first, but either it grows on you after a while, or it dulls up a little.

After I get it glued up I can but the ground on it, and then start the varnish. While waiting for varnish to dry I have a fingerboard, pegs, tailpiece, saddle and nut to make. I have a hunk of ebony that isn't all black. Hope it works.

Tap Tones

Well, I am gluing up the instrument. I decided to check the tap tones and weight of the plates beforehand. I used to use a great program for fft analysis called Sakuro8, or something like that. It doesn't work on Apple. I've tried to use Audacity because it will supposedly work on Apple, but I don't see how to get it to do anything. There is a panel, but nothing is active on it. It is merely an exercise in futility. I used my electronic keyboard instead. Anyone know how to get it to work? It isn't user friendly like the Japanese flute program. That one was great.

The back is about 102 grams, and the tap tones are fairly close to each other. The lowest is E3 then C4 and the ring note is Eb4. Almost an octave, with the the fifth a little high, and the octave a little low. The belly is harder to find the notes for. The low note is low; Bb2. Then the next note comes slightly more than an octave up at B3, so it is a semitone lower than the back there. The ring tone is elusive. I hear different notes depending on where I hold it. I hear a cluster of notes: E4, F#4 and A4. None of them particularly ring like the other two do. The belly is 75 grams.

Using the formula to gage stiffness we have 294 squared times 102 = 11.1 and, 370 (I used the F# a fifth up from the B) squared times 75 = 10.3.

They both seem to flex about the same to me. The edges are quite flexible, but the center is quite stiff. Maybe I could have gone thinner on the belly. Let's see what really stiff can do.

Edge Method

I generally use the edge method given by Roger Hargrave in his article on the Working Methods of Del Gesu. I found it originally here: http://www.vsa.to/index.php?option=com_content&view=article&id=76:classical-edgework-by-roger-hargrave&catid=20:selected-articles&Itemid=140
That is what I used for this one. It would have worked if the purfling was 2.5-3 mm tall, and if my platform was flat; but it wasn't, and the purfling is only 1.8 mm. After fixing it up, I have come up with some alterations to the method if you are making a model with thin edges. Here is the plan:

What this does is make the platform lower, while keeping the edge at about 4.5 or so. Here is what I was dealing with:

And this is how it ends up. I still need a little work on the edges, but it looks much better than it did.

Bite the Bullet

I am going to replace a lot of the purfling on the back I'm making. The model has thin edges, and a thick center strip, and the thin edge combined with short purfling didn't work. When it starts getting thin it looks shabby, even if it is still there. The belly must have had a taller piece of purfling, and it was stuck in the groove within a mm or two, and not .5 mm, and I stayed somewhat further from the purfling when bringing the recurve in, and I may have cut the back a couple tenths of a mm thinner.

The bottom line is: the belly looks ok, but the back needs some TLC.

Cutting the groove back into where it was glued, and may still be glued in is no picnic; but I see no way out. NOt all of it will need to go, but much of it will. I am thinking of making my own purfling. I've thought of doing it with thin strips of wood, that aren't glued together. I've done that, and it works fine. But I think it may work better to glue the strips together in the groove, using fish glue, or casein; and then pulling them out, and re-gluing like normal purfling. The hardest part of loose strips are the corners.

Well, I have work to do.

How Long Does It Take

I'm always asked how long it takes to make a violin. I don't know. It doesn't take as long as you would think. I'm getting faster, but I never kept track of time; it's a lot of bother, and I'm not trying to figure out how much an hour I'm making on them.

The violin I'm making for the VSA was going along fine. Then the back curled up on the ends like a potato chip! The wood had crazy grain, and I was using water on it to make the planing easier. I tried to flatten it out by getting it wet and clamping it to a board. That didn't work. The next day I took it off. It looked somewhat better, but flexing it I heard popping noises; it was pulling away at the center seam, I ended up with a 2 mm wide gap on the bottom third of it.

I split it and re-joined it. I glued it up. Both of those were not easy to do. Then I noticed that the button was about 2 mm off center, and naturally it was off on the side that was cut about 3 mm closer to the centerline. I can't use it for this; maybe for something else, but not for a competition. The new one I made has a lower arch, and a higher tap tone, so maybe it was the one I was meant to use.

Our grandkids, and daughter, and son in law were coming up, so I knew I wouldn't have time to work on it. I had another back glued up, and started on it. I kept track of time and I got it down to the same weight (130g) as the other was when it conked out on me in 9 hours. In 3 more hours I had it ready to clean up the outline, and put in the purfling groove. So 12 hours to get it semi-finished and at 112 grams. Is that a decent time? I don't know.

Today I wanted to get the groves in. I haven't made the fixture for the rotary tool yet (I need to get an 18 mm tap), so it is a job for a marker and a knife. I used my magnifier, and it made a big difference. I don't see anything that looks terrible, I'll know more when I get the purfling glued in. I found a thin flat file that works well for flattening and trimming the groove to size. It took 2 hours a plate to get them done. Is that a decent time? I don't know.

I do know that 4 hours of knife time gets my hands sore!

Sap Pocket

I am making a violin for the VSA Competition. I was going to go to Arizona this year, but our daughter is coming up here in a couple of weeks, so my wife asked if there was somewhere else to go. When we found out the VSA was in September and not December, she asked why not do that one. I shouldn't have any problem getting it finished. The ribs are done. The back and belly are roughed in. The neck and scroll are almost finished. The wood is really cool, and the archings seem to be really strong.

I ran into a sap pocket on the inside of the belly. I thought that maybe it would be either right where the f hole would be cut, or somewhere that it wouldn't be right on the edge of it. I lucked out. It is right under the upper wing.

I took a few pictures of it but I can't figure out how to get close ups with this camera, and they are all blurry. This is it after cutting it open to fit a patch. I cut a piece of spruce tall enough so I could hold on to something to fit it.

It doesn't take long scraping with a knife, and checking with chalk, before it is ready to glue in place. I saw of the excess, and trim it down to leave it only a few mm's proud of the surface.

I finally found that I could shoot through the magnifier, and it worked pretty good. This morning I trimmed it down, and it came out half way decent; almost like a trained professional. I tried to take some photos through the magnifier again, and most of the didn't work! What is a good camera, that takes good macro photos? Anyway, here is the finished patch.

The long arch is almost finished. Most of the stock is in the recurve and the edges.