Double Bass Replacing Kay fingerboard — tips?

[Steven Ayres]

I've just started work on replacing the thin ebonized maple fingerboard on my Kay C-1 with a B-grade slab of Indian ebony. I'll have to trim the new fingerboard down to width, and plane to shape, of course. Looking for tips from the pros here.

I've cut tapers for furniture. How do you pros go about trimming an existing taper to another angle?

The fingerboard is thick enough that I see an opportunity to cut it as a wedge and raise my overstand some. Is this practical? A common practice? Any risks?

The fingerboard is off, the neck will remain attached to the body. Should I consider adding internal reinforcement to the neck? Carbon fiber, or what? Sources? How about the heel?

Anything else I should consider? Thanks.

 

[1st Bass]

I expected someone else to answer: maybe they still will speak up. Meanwhile...

What I do on smaller instruments (I have only replaced a couple of bass fingerboards) is to clamp the FB in place, exactly in line with where the nut will be, and centered as closely as possible, then trace down the sides of the neck with a pencil, a pen or a knife blade, to transfer the taper of the neck to the FB. I cut close to those lines, so that it fits nearly perfectly, then plane it to the thickness, and the angle I want. Once it is close in all directions laterally, and airtight against the neck, I hollow the underside to the thickness I want for the overhanging portion, glue it in place, and (after the glue dries) begin scraping for final shape, so that it blends perfectly with the sides of the neck. I dress the board, using a small plane, a scraper, a file, and several grits of abrasive paper, wrapped around a hard block, either plastic or wood...culminating in 1500 grit, usually. The scoop should be correct before you begin sanding.

While you have the board off, I would definitely consider inlaying a strip (or two...there are various acceptable configurations) of Carbon Fiber. I got mine from DragonPlate.

 

[Steven Ayres]

Thanks for the tips! A detail —

I cut close to those lines, so that it fits nearly perfectly, ...

What do you use to cut it?

 

[robobass]

I'm not a luthier, but have done some fingerboard work. I would use a table saw for the edges. I attach the FB to a piece of HDF board so that I get an accurate cut. Tapering the bottom of the board will be more difficult. Unless you have access to a CNC router or knee mill it just seems like it would make more sense to add a tapered shim.

 

[Greg Clinkingbeard]

First, I would not thin the board on the nut end. I don't think you would gain much projection. Kays have thin necks to begin with so I would leave the board thick or add a tapered shim.

To narrow a fingerboard I just clamp it in the wooden vice on my bench and go at it with a Stanley #4 bench plane. After gluing, I'll use smaller planes, scrapers and sandpaper on a block.

 

[Ed Fuqua]

Hey @james condino!

 

[Dean Foster]

I’m not a luthier either but I do know that ebony dust is toxic. Just something to consider if you’re working in a confined area.

 

[Steven Ayres]

I would definitely consider inlaying a strip (or two...there are various acceptable configurations) of Carbon Fiber. I got mine from DragonPlate.

Good tip! I checked out the Dragonplate site. The Invalid Link Removed is particularly interesting for this application. Anyone have direct experience with this?

 

[1st Bass]

Thanks for the tips! A detail —

What do you use to cut it?

There isn't a lot of extra-- I just plane it off.

And any dust can potentially be a problem. Many people do react to Ebony dust. Probably more react to Rosewood (I do, very badly) and even more to Cocobolo. I think they may all be related, so do wear a dust mask at least.

I used two strips, inlayed at an angle to one another, radiating out from center. But that was just me, reinforcing an old Kay. If the real bass luthiers here will share their methods, they are undoubtedly better sources.

 

[james condino]

Hey Ed!!!!

'Apologies..I've been over at the Redneck Riviera with the family all week surfing.

Once I heard B grade slab of Indian ebony, I left the conversation and went to screen saver. If you are going to all of that trouble, the last thing you want to do is use poor grade materials- you already have a lame fingerboard; I'd recommend one of the mid grade from International Violin or MET. Those may not be perfect, but they are fair priced and decent quartered. The Indian low grade ones tend to be flat sawn and will warp within a few months- a supreme bummer after doing all of that work and then having a customer wanting it redone. I look at it like $100 extra for materials vs 20 hours more bench time to redo the whole thing and then still spending for the $300 fingerboard (plus whatever the lame one cost). The great thing about international and MET music is that they will let your order 3 or 4 and select the best one and then return them for a modest 10% restocking fee. I do that all of the time, especially with fingerboards and bridges.

Dragonplate and JB Alred are fantastic folks to work with and they make 1000s of different configurations of carbon fiber. I use about 20 different variations, depending upon the need. The D tube works great for some applications, but for the super thin Kay neck it will only leave about 1/8 of an inch of wood- that is pretty close and no margin of error. I'm also mixed about leaving a big hollow tube in the neck in terms of potential wolftones and such. I usually use several of the 1/4" x 3/8" for Kay necks. Extra thickness and shims are my preference, but not everyone has big hands and plays 5 hour gigs going for Django trio speed records every week like I do. There is an article series in American Lutherie from a couple of years ago that details the whole neck rebuilding process and there should also be an upcoming article in Guitarmaker (ironic- a bass article!) from last years workshop at the ASIA convention that covers the whole neck rebuild process for old Kays. I have a fellow doing some video shoots on the subject, but it always comes down to waste more time on the computer or actually get some paying work done!

Wood reactions- oh yeah!!!! African Blackwood is my current top of the list. Ebony dust is no fun. After everyone here tried their best to convince me other, I wound up buying one of the small Lie Nielson scraper planes just for fingerboard work and I honestly love it. It performs excellent and my dust issues have been reduced by about 90%.

Good luck with the project. In the end, anything you do will likely be an improvement over the often questionable factory work and it will live for another 50 years of fun gigs!

j.
www.kaybassrepair.com
www.condino.com

 

[Steven Ayres]

The Indian low grade ones tend to be flat sawn and will warp within a few months ... The D tube works great for some applications, but for the super thin Kay neck ... I usually use several of the 1/4" x 3/8" for Kay necks.

Thanks James, those are good tips!