Double Bass Neck-block modification?

[Mike Goodbar]

I’ve been doing a lot of imaginary bass repair since salvaging an unplayable blockless wonder from a friend’s basement about a year and a half ago. Mind you, I have not actually touched the bass since rescuing it, but let’s concede that you can’t have too much mental preparation.

I’d like to turn this from block-less to “block-ful”, and in doing so, increase the neck’s overstand, which is currently quite shallow. This would, I imagine, necessitate adding length to the neck’s heel?

But how practical would it be to essentially build that extra heel length into the new block itself, extending over the top of the corpus, in effect resulting in an extremely fat “button?” This would turn it from a 3-piece to a 2-piece joint, which I can only suppose would be preferable.

Of course, I’m not claiming to possess any of the skills required to make this happen, but is the theory sound?

 

[tyb507]

The button is not part of the neck block, it is part of the back. What I think you're proposing is cutting the neck block is such a way that it fills the space left by increasing the overstand, between the heel and the button? Still a "3-piece" joint, and probably more complicated than it's worth. You'll need a much bigger blank for the block, and you'll have a strange looking section of spruce or willow in your neck heel. Just add a piece of matching maple to the heel!

 

[Eric Hochberg]

I believe additional material also has to be added to the heel to fit in the block if you use the original neck.

 

[1st Bass]

I'm pretty sure you are going to find that the neck block is narrow for the mortise, too, when you move it up to make a taller overstand...or is this a dove-tailed joint?

 

[Mike Goodbar]

The button is not part of the neck block, it is part of the back. ..... You'll need a much bigger blank for the block, and you'll have a strange looking section of spruce or willow in your neck heel. Just add a piece of matching maple to the heel!

Right about the button...I was grasping for a way to describe what I had in mind. The bass has a very dark varnish, so cosmetically it might not be a big deal. But I can see how making the thing would be a headache. Is the maple extension simply glued on, or is there dowel work, or (god forbid) ironwork involved?

I believe additional material also has to be added to the heel to fit in the block if you use the original neck.

Was afraid of that...have not seen what the 'foot' looks like. Maybe the heel extension could be integrated into that additional material in some way.

I'm pretty sure you are going to find that the neck block is narrow for the mortise, too, when you move it up to make a taller overstand...or is this a dove-tailed joint?

There is currently no neck block or mortise at this point. The neck is glued in similar to an acoustic guitar. A new block would have to be fitted and mortised unless I just wanted to keep the current set up (which I really don't).

Thanks for the comments! Maybe I'll have some time to actually work on the thing his summer, at which point I'll be posting here frequently!

 

[KUNGfuSHERIFF]

This is major surgery. Tread lightly.

 

[Eric Hochberg]

Have you heard the bass yet? If not, if you can get it playing, at least you'll know something about the sound before you do major work. The sound may tell you if it's worth it.