You just use a gouge to cut it down to the surface of the wood. That figure of 1/2 the depth of the purfling is pretty accurate by my knowledge. You should ideally end up with the purfling about 1mm deep after you’ve cut the edge channel, but it can often end up shallower than that if you’re not careful. Fortunately, I didn’t have that problem with any of mine, but if you make the purfling too shallow, then sometimes you’ll end up cutting all the way through it when you carve the channel. I hear that’s a real pain in the butt to fix.
And, this is what a bass bar looks like when it’s all done and prettified. It’s surprisingly fun to do, though it makes me a little sad to know that whoever ends up playing this instrument will never see it, and likely won’t even know that it’s there at all.
Fitting the bass bar is awesome, mostly because it wasn’t as hard as everybody told me it was going to be.
Don’t get me wrong, it was still plenty hard. That’s a given when you’re trying to fit two three-dimensionally curved surfaces together perfectly. I spent a lot of hours chalk fitting my bass bars. The first one took me three days, and the second took me one.
The bass bar is a bar on the inside of the violin that stiffens one side in order to give the bottom end some oomph. In order to fit it, you first match the curve of the plate as much as you can, then you get to work actually fitting the bar.
Step 1. Apply the chalk.
Step 2. Put the bar in position and gently rub it into the chalk.
Step 3. Remove the bar and shave off any part that has chalk on it.
Step 4. Check for gaps.
Step 5. Repeat previous steps until the heat death of the universe or until there are no gaps between the bar and the plate, whichever comes first.
Step 6. Remove the chalk with a stiff brush. (Pain in the butt)
Step 7. Check for gaps.
Step 8. Dry clamp. Check for gaps. With a flashlight.
Step 9. Glue, clamp, and check for gaps.
Step 10. Let glue dry, party like it’s 1999, and check for gaps one more time because you can’t ever be paranoid enough.
Bonus step. Check for gaps. If there are any, punch whoever’s sitting next to you because it’s their fault.
One of the cool things about going to school here is that we’ll often get to see some really awesome instruments. Like today:
1. The 1691 GI Strad: $3 million.
2. The 1701 Markees Strad: $7 million.
3. The 1718 Firebird Strad: $11 million.
4. An 1866 Postacchini: $132,000
Call me a sheep, but my favorite was the Firebird, and I’m guessing it was the same for the guy who played them, because that was the one he played the most on.
After you’ve finished with the rough graduation, you start working with the finger planes. This is a picture of the inside of the back who’s center seam I had to repair. You can see some deeper holes in a line across the instrument at about the bottom corners, that’s where the thickness changes from 3.5mm to 5 mm. Right now, I’m in the middle of blending out that slope.
The repair didn’t go as planned either. For some reason, the center seam didn’t quite go all the way back together. I’m going to leave it for now, and then retry when I’ve got the plate down closer to the final thickness, because it’s easier to repair when it’s thinner. What I’ll likely end up doing is wetting the seam, then heating it up with the heat gun, and re-clamping with a little more pressure.
Rough graduating out one of the tops. The holes are for marking your target depth.
This step was actually really fun. You just take a gouge and hog away the wood. The only scary part is the occasional time when you slip with the gouge and tear a chunk out of the other side, which is yet another reason why I love working in maple a whole lot better than spruce. Maple is hard, so if you slip, the chunks you take out are smaller. By the time I finished with the backs, I’d gotten the technique down well enough that I only slipped one or two times, and fortunately, none of the mistakes were deep enough to affect the finished product.
I popped the center seam while gouging out the inside, so I got to learn how to do a seam repair! First, you put packing tape along both sides of the center seam to prevent the glue from getting all over. Then you run a bead of glue down the inside and flex the joint to work it in, then you tap it with your finger to force the glue further in. Wipe away the excess with a damp paper towel. Be sure to work fast so the glue doesn’t set up on you.
Flip the plate over, and repeat the process with the outside, except for the wiping. After that, you clamp it, then you wipe away the excess. Move one clamp, wipe away the glue below it, and replace it with wax paper underneath to prevent sticking. Repeat for the other clamp. Let dry overnight.