Double Bass Removing a bow from a double bass neck.

[rodthebass]

I have seen a few instances where someone has had trouble dealing with bass necks not dealing too well with string tension.
Although I am essentially a luthier of bass guitars come bass player, some years back I was approached by an acquaintance to help him sort out his double bass which had a surprising bow in the neck probably due to the tension of the strings over a number of years. It wasn't a particularly special instrument but was fairly well made.
I wasn't getting particularly excited about it because it really didn't sound very good when you played it as it had no sustain and perhaps just a very dull tone.
I decided to take the fingerboard off and having done that I put a couple of routes running for most of the length of the neck which gave me a space to fit a couple of pieces of 3mm x 12mm steel, the 12mm tapering to 8mm towards the tuning key end.
Using a router cutter just big enough to allow the 3mm steel into a couple of slots I then bent the neck to a little bit past straight to compensate for the tension in the neck timber, and then I used epoxy glue to hold the steel strips in place and the neck was held in this new position until the epoxy had hardened. After 24 hours I allowed the Steel strips to take over holding the neck straight. I then glued the fingerboard back in place and discovered that years of use had made the fingerboard quite uneven and I used my years of woodworking skills as a furniture maker to level the Ebony fingerboard surface. I then put all the rest back together- ie the bridge the strings and did a set up on it and by the time I had finished it was a very nice instrument to play. It had wonderful sustain quite a pleasant tone and he was one happy customer.

 

[Don Hergert]

Hmmm. Glad it worked, but your description leaves me with some questions...

"Leveling" as used with guitar-necked instruments is sort of a foreign term for double bass fingerboards... A properly "dressed" double bass fingerboard is pretty complicated, considering the combination of an expanding radius and a different degree of relief (aka scoop) for each string over the length of the fingerboard. This relief has to be built into the fingerboard, since there is no truss rod that can allow or insert relief. Did you also "dress" the fingerboard allowing for that relief for the kind of strings being used?

 

[eh_train]

"Leveling" as used with guitar-necked instruments is sort of a foreign term for double bass fingerboards...

Don,
I'm thinking that the leveling was to the underside of the fingerboard, so that the newly flat neck and the newly flattened fingerboard could be glued together nicely.

A properly "dressed" double bass fingerboard is pretty complicated...

Agreed, 100%!

In the OPs scenario, I'd bet plenty that the fingerboard needed to be dressed afterwards. You can't substantially alter the geography of a neck and expect the playing surface to work well without dressing...

 

[rodthebass]

Hmmm. Glad it worked, but your description leaves me with some questions...

"Leveling" as used with guitar-necked instruments is sort of a foreign term for double bass fingerboards... A properly "dressed" double bass fingerboard is pretty complicated, considering the combination of an expanding radius and a different degree of relief (aka scoop) for each string over the length of the fingerboard. This relief has to be built into the fingerboard, since there is no truss rod that can allow or insert relief. Did you also "dress" the fingerboard allowing for that relief for the kind of strings being used?

Hello Don,
I am quite flattered that my first offering to this site concerning a little aside that I had performed Nearly 30 years ago should draw in your discerning attention.
Thankfully, as much as I love the sound of a well played bull fiddle, there is no danger that I shall be let loose on anymore as I just don't have the time or inclination.
Taking into account my fading 77 year old memory, when I was shown the bass, the neck had a real ski jump bow in it, hence my feeling that the neck on its own stood no chance of doing its job without some form of bracing.
Yes I am well aware of the need for an element of relief in any bass or guitar and yes as I reattached the fingerboard to the neck I took this into account.
You may notice that I have been refining the detail a little more here regarding your questions. I did observe that the fingerboard had particular profile that I felt needed to be adhered to as much as possible, but I could also see that the mild undulations caused by years of playing the instrument in favourite positions had caused slight indentations in the fingerboard. This I felt was something that definitely needed some very careful attention.
Ultimately putting it all back together and stringing it up, my friend and I were quite taken aback at how well the instrument sounded and how easy it was to play.

 

[Mark_T]

My bass has ipe stiffening strips embedded in the neck, placed there by the original builder. The rationale on ipe was that it would add some stiffness but not so much that it couldn't breathe or flex with the wood of the neck.

The bass is only about 5 years old at this point so no way to know if that was a good call or not but so far so good.

 

[rodthebass]

My bass has ipe stiffening strips embedded in the neck, placed there by the original builder. The rationale on ipe was that it would add some stiffness but not so much that it couldn't breathe or flex with the wood of the neck.

The bass is only about 5 years old at this point so no way to know if that was a good call or not but so far so good.

Funny, with all my years as a woodworker I have not come across ipe?
About 27 years ago I thought I'd take advantage of my years of making fine furniture, joinery, music and audio electronics and made a few bass guitars most of which I sold to pro musicians. I kept 2 for my own use one of which - my long scale fretless 5 string, I used for a submission to the American company "Best Bass Gear".
I have tried to attach the file unsuccessfully and so have been reduced to giving you
- ( Bass of the Week) Harper 01/05 -
which will get it on Google.
It has a fairly comprehensive description of my angle on neck bracing covered in the text.
I apologise for the typo where I called the bone nut a bridge.
If you do take the trouble to download it, I hope it proves useful.