Round Laminated neck / fretboard..

[SamJ]

Again, thanks a lot for your expert advise here guys.. on the topic of the Jazz bass I'm having made..

I am considering having him do a Round Laminated neck. I guess its where the maple neck is curved, and the ebony fretboard is concave curved at the same radius and then laminated, giving you more maple and less ebony which pushes on the maple to possibly create back-bow. This is to strengthen the integrity of my new Jazz bass as I'm using a 1/4 sawn flame maple on the neck wood for added bling..

Anyone have any thoughts either pro or con this idea?

I guess Leo Fender began doing this in the early 60's on some models, but that may have ended after he sold the company..

[DavidRavenMoon]

Originally Posted by SamJ

I guess Leo Fender began doing this in the early 60's on some models, but that may have ended after he sold the company..

You have to look at the original Fender bass necks as a reference. Leo was a machinist, and he tried to find ways to do things that were easy and cheap. He didn't have fingerboards on his necks... he just put a radius on the fretboard surface, and put his frets on that. It was an easy way to machine a neck. And it saved money... he didn't need a fingerboard, and all the steps involved in putting one on a guitar.

He saw some of his guitars that had been played a while and the finish wore off the fretboard, and the wood got dirty. He hated the way it looked, so he went to using rosewood fingerboards. But instead of doing it with usual way, he kept putting his truss rods in from the back, and putting a radius on the neck, and he instead just glued a rosewood cap to the fingerboard surface.

The rosewood board was more for looks than anything else. I doubt it adds much to the stiffness of the neck. It's too thin.

Having a thicker fingerboard will give you more strength than the way he did it. So will having quarter sawn neck wood, which is something Fenders don't have. Also, ebony is a much harder wood than maple is.

The best thing you can do for a stringed instrument neck is add carbon/graphite rods. It adds some stiffness, but the biggest improvement is eliminating dead spots, and giving a nice even tone all over the neck.

[Keith Guitars]

This is an interesting one - the Fender necks that were
built this way often worked just fine.

I can't say I would prefer to manufacture a neck this way,
since it seems like more work than gluing the assembly flat
and rounding afterwards.

More recently, Rick Turner has been building necks this way
for a while, and IIRC he says they behave very well.

I think the potential for backbow has less to do with the
shape of the joint than it does with the moisture content
of the wood. Use epoxy to glue the FB on if you're really
concerned about movement...

Also - (and this is just my two cents) - if neck stability is
a concern from the outset, as it seems to be, don't use
flame maple for your neck. Bling is fun, but flame is just
not as stable/reliable/stiff/etc. as plain QS hard maple.

Peace,
Martin

[DavidRavenMoon]

Originally Posted by Keith Guitars

I can't say I would prefer to manufacture a neck this way, since it seems like more work than gluing the assembly flat and rounding afterwards.

This is true, but if you are all tooled up to make necks with the radius built in, and a way to fret them (they used to push the frets in from the side), it might be easier to add a curved rosewood cap, then to retool...

More recently, Rick Turner has been building necks this way
for a while, and IIRC he says they behave very well.

It's also the way Parker Fly guitars are made. The top of the neck has the radius, and a thin curved composite fretboard is glued on.

I don't think gluing on a freboard like this would affect a backbow either...

[SamJ]

good stuff guys thanks.. The only way we're going with flame maple is if he can find a good 1/4 sawn piece that can accept the stress.. otherwise bling is out of the window! This being a custom shop Master Built, I was assured it would be 1/4 sawn wood..

[Rick Turner]

I do not agree that a thicker fingerboard makes for a stronger or more stable neck. Nor do I agree that a quartersawn maple neck is significantly or even measurably stronger. Do some actual tests on square pieces of maple, clamping them and weighting them. You might be surprised... BTW, Roger Sadowsky is in agreement on this, for what it's worth. My Renaissance and Electroline bass necks have been incredibly trouble free over the past ten years. Our warranty work load on them has been insignificant.

The most stable wood necks I've made in maple for basses have two graphite bars, a two way acting adjustable rod, slab maple shaft, and rosewood fingerboards that are .075" thick and are sawn clear through for fret slots. That's hundreds and hundreds of bass necks.

I caution against accepting accepted wisdom without testing all the components there in. Also, I recommend reading Hoadley and the Wood Handbook on the strength of various cuts of wood. The primary positive quality for quartersawn woods is lower movement and greater stability across the vertical grain. It's not that big a deal with a neck if the wood is well seasoned. Makes a lot more difference in something like and acoustic guitar top or back.

[SamJ]

we are going with this piece of wood...

It's not flame, but rather a figured, birds eye type.. and it's 1/4 sawn (something Dennis feels is critical on a bass neck of maple, especially figured wood), as such the Luthier (Dennis Galuszka) is comfortable with a normal "Slab" fret board..

[FBB Custom]

Uhhh... bird's eye is not supposed to show on radial surfaces.

And what's the guy in the background doing? Looks like he's passing a kidney stone.

[SamJ]

Originally Posted by FBB Custom

Uhhh... bird's eye is not supposed to show on radial surfaces.

And what's the guy in the background doing? Looks like he's passing a kidney stone.

Not sure if that a birds eye, or what, but it looks nice, and it's 1/4 sawn.. I'm oking it.

The guy in the back (John Cruz) is yawning... I think he needs his morning cup of coffee!

[erikbojerik]

There is a difference between strength (instantaneous stiffness) and stability (stiffness over time). I would agree with Rick that FS and QS have about the same strength, but I think its been known for some time that QS is more stable over time.

From a structural standpoint, the curved shape of the neck-fretboard joint should indeed improve the stiffness slightly over a flat joint.

[pilotjones]

Originally Posted by erikbojerik

From a structural standpoint, the curved shape of the neck-fretboard joint should indeed improve the stiffness slightly over a flat joint.

I disagree from an engineering standpoint.

Please detail your thinking here. While a curved member is superior to a flat member in stiffness if both have the same mass and are standing alone, that argument does not apply to a laminated neck, with insignificant shear strain on the glue plane, such as this.

[Dusty G]

Originally Posted by FBB Custom

Uhhh... bird's eye is not supposed to show on radial surfaces.

And what's the guy in the background doing? Looks like he's passing a kidney stone.

Literally laughed out loud!

[SamJ]

Originally Posted by Dusty G

Literally laughed out loud!

ok, ok now guys.. enough picking on Mr. Cruz!

I swapped the picture out so I can get us back on the wood, and not the board Custom Shop employee!

[erikbojerik]

Originally Posted by pilotjones

I disagree from an engineering standpoint.

Please detail your thinking here. While a curved member is superior to a flat member in stiffness if both have the same mass and are standing alone, that argument does not apply to a laminated neck, with insignificant shear strain on the glue plane, such as this.

Note that I said a small improvement over a flat joint, for the same reasons you stated above.

The small amount of bow induced by the string pull will create a little bit of shear stress in the neck if the fretboard wood is stiffer than the neck wood (due to different species, different grain orientation, whatnot). A curved joint will be a slight improvement, but probably not enough of a one to justify the work that would go into it IMO.

[pilotjones]

It's a tangent for sure, but I still disagree. There will be a shear stress distribution across any given transverse neck section. With either fingerboard construction, or with a single-piece maple only construction. Having a stiffer-wood fingerboard moves the neutral axis closer to the fingerboard--but not up to it. Regardless of any of this, though, there is some shear stress at the glue joint. If we assume the glue capable of holding the shear, the shape of the glue plane itself does not affect the overall beam stiffness.

Only if we were to consider the fretboard and the main neck piece as separate pieces that are free to slide (that is, if there were a low shear stiffness to the glue) would the shape of the fretboard make the kind of difference that you are suggesting.

Also, in the conventional-fretboard neck, there is more rosewood present than in the curved-fretboard version, so it should be stiffer.

In any case, either construction is good, and I think SamJ should make his choice based on which version of vintage appeals to him, rather than a structural reason.

[SamJ]

Hey, while I've got this assemblage of serious knowledge of guitars, woods and Luthierie... maybe you all can give me your take on "Brazilian Rosewood" vs. African and Indian Rosewoods.. Worth the MAJOR extra cost?

[pilotjones]

Brazillian is expensive because it can no longer be imported or exported. It is what was normally used in the past for fretboards, before it became endangered. So I believe any that is currently being used in the US is old, pre-CITES stock.

As to whether it's worth it, I'd be the last guy to comment on wood species of fingerboard vs. degree of real effect on tone vs. value to you.

[erikbojerik]

There are lots of nice rosewoods out there that will do the job, and you won't have to pay the big bucks. I like cocobolo, though I know the dust from working it is very problematic.

[tangent] yes PJ, I was thinking theoretically "...in the case that the glue joint is not totally secure...", given decades of string pull, in and out of hot car trunks, who knows. In practice, it could be quite difficult to get a dry joint match that is free of gaps where extra glue would sit....meh, way easier and just as good to make the joint flat. [/tangent]

[pilotjones]

Originally Posted by erikbojerik

[tangent] yes PJ, I was thinking theoretically "...in the case that the glue joint is not totally secure...", given decades of string pull, in and out of hot car trunks, who knows. In practice, it could be quite difficult to get a dry joint match that is free of gaps where extra glue would sit....meh, way easier and just as good to make the joint flat. [/tangent]

Sounds good.

[BurningSkies]

Originally Posted by SamJ

Hey, while I've got this assemblage of serious knowledge of guitars, woods and Luthierie... maybe you all can give me your take on "Brazilian Rosewood" vs. African and Indian Rosewoods.. Worth the MAJOR extra cost?

I paid the extra for my Tele...and it was worth it. I can't say from a tone perspective that it made a difference, but it's a really beautiful wood. It seems to have a more complex grain than any of my other RW FBs?