French Bass full restoration

[Arnold Schnitzer]

Nice pics and work, Matthew. Brian, will you be starting up a thread on your endpin experiments soon? How is the Tarrantino sounding?

[Brian Gencarelli]

Hey Arnold,

Yes, I am still working on some ideas, but things are going well. Harrison is in town and I had him play it for me with a couple of different pins. I think I may just plug the regular endpin hole with a tailpiece hanger and just use the Laborie. I am starting to get used to it. Been tweaking the set up some, and I about have it dialed in. It sounded really good with John playing this morning.

I will be posting some things on it in the next few weeks. I just finished reorganizing my shop and now I can actually walk to my Lathe! Now that I have figured out how to play in that position, I can experiment with the different materials.

Best,
Brian

[Steve Alcott]

So how's the bass coming along, Matthew?

[Matthew Tucker]

OK, OK


Once the graft was glued, I checked the cheeks and back.



The repair join was good, but it was a toss-up between an inlay repair of the back of the scroll and re-doing the cheeks. Given the state of the scroll, I decided to re-cheek as well. Also, there is the little broken bit of the edge that I put somewhere and now cannot find ...



While I was waiting for suitable repair wood to arrive from Europe, I hollowed out the pegbox.

That's the Lignum Vitae carver's mallet my Mum gave me a few years back.



The black mark is a woodpecker peck, or a nail hole, or something. It doesn’t worry me as it’s not in a critical position. I may chisel it out altogether eventually.




The sides were planed back as little as possible and holes filled where needed with new maple. These will mostly be covered and the holes drilled out again, but a bit of repair wood in there will minimise splitting.









The scroll this morning, new cheeks and in process of shaping. I was careful to document the chamfer before planing off the sides, so I can try to make the new chamfer as close to the original.



The sides of the scroll will be probably 1.5mm thicker than the original, and I will probably finish the top of the cheeks with a gentle scoop into the existing volute, instead of a smooth transition, as I want to keep a good thickness of wood up near the top of the pegbox where it counts.

On the pic below I have redrilled the guideholes for the tuners; I measured these with calipers using triangulation from the lower corners before gluing on the cheeks. You can also see a tiny hole where I used a pin to accurate register the cheeks for gluing.



The new cheeks were cut from a flamed violin back wedge. Even though the grafting neck block itself was rather plain maple, I decided it would be a pity not to try to match the flame on the rest of the instrument, in the scroll. Due to the smallish size of the back wedge, the flame is angled back a few degrees from normal.

It's nice flame, pity my lighting is so crap.

[Steve Alcott]

Looks great, your lighting is fine, and thanks for keeping us up to date on the progress.

[Matthew Tucker]

If anyone has any real, practical, tried tips about keeping a flatback flat for reglueing, send them through. This one wants to curl up like a potato chip. I've tried lots of things, dampening and clamping flat, using heat and clamps etc, drying out under lamps etc, but as soon as I pull the clamps off it starts to curl again. And not in the direction I want it to. Quite frustrating!! I'm now considering sealing the inside surface to slow the moisture loss.

[JoeyNaeger]

Maybe you need to overbend it the other way? The cheeks look great by the way.

[Brian Gencarelli]

Originally Posted by Matthew Tucker

If anyone has any real, practical, tried tips about keeping a flatback flat for reglueing, send them through. This one wants to curl up like a potato chip. I've tried lots of things, dampening and clamping flat, using heat and clamps etc, drying out under lamps etc, but as soon as I pull the clamps off it starts to curl again. And not in the direction I want it to. Quite frustrating!! I'm now considering sealing the inside surface to slow the moisture loss.

The back on my Tarantino was the same way. When I took it off it when haywire. Looked like a big pringle. I did the same thing and clamped it flat. I also added the center strip to it, which was a crazy challenge. every thing I did I tried to make sure that it was clamped flat for final shaping. I think that it finally relaxed, but I just kept it in a really regulated room. (Clamped to the dining room table... the wife loved it. )

I think it finally relaxed to a point that I could get it re-joined, but it didn't come out perfectly. I had at least one or two proud spots and one dip. I think that was due to a flaw in my clamping process. Which I will know better next time. However, the bass sounded much better after taking all of that stress out of the back and making it function as a unit.

Do the halves at least match in their warpage? are they going different directions?

Don't have all the answers for you, but hope you get it worked out.

Best,
Brian