Aluminium Part 3

[BigRedX]

Some of you might not consider this to be porn based on the comments it elicited when this appeared on eBay...

But I present for your general enjoyment and education the Born To Rock F4b.





Constructed from aluminium tube and strips, it features and innovative neck arrangement that doesn't require a truss rod. However unlike the Kramers and Travis Beans of the 70s it doesn't rely on the neck thickness and material to avoid the need for a truss rod, but because the strings don't actually exert any of the pulling forces that a normally constructed bass neck would be subject to.

The [url="http://borntorock.com"]Born To Rock web site[/url] makes quite a big deal of this feature, but without actually seeing it for yourself (and the lack of decent photos doesn't really help) you don't realise what a smart idea this is.

The strings are anchored at one end by the machine heads attached to the body...



... and at the other by a plate which is attached to the 'arm' that runs above the neck from the top 'horn'.



The neck from the nut to the bridge is actually a completely separate piece. It is supported at the nut end by a simple 'ball and socket' joint



and the bridge end rests on a section of the body skeleton.



It is kept in place simply by the tension of the strings pushing down on the nut and the bridge which are the only two places that the neck assembly actually touches the body and arm.

As the strings are tightened up to pitch the tension is taken up by the tubing of the body and the arm. With the strings off the arm has a slight back bow and with the strings at standard pitch there is slightly more relief in this tube that a standard well set-up bass. Because none of the string tension is doing anything to the neck other than keeping it in place relative to the body it completely eliminates the need for a truss-rod and also means that the neck can be very slim.

The neck itself it basically a long piece of T section aluminium with the top of the T forming the fingerboard, and short upright giving the depth to the neck the gaps being filled with wood in a similar way to that of the Kramer necks, and the whole of the back of the neck has been finished with a metallic silver paint. The fingerboard has a standard radius and a thickness of only 17mm. I don't think that any of my other basses come close to that sort of slimness!



The frets are not at all conventional being what looks like stainless steel rods set into slots in the fingerboard and the tops profiled like a traditional frets. There are dot markers inlaid into the fingerboard but surprisingly none on the side. However the previous owner has added some using a permanent marker.



The neck has a full complement of 24 frets, although the position of the tube joining the two 'horns' of the body together slightly restricts access to the last few. Since the neck doesn't actually come into contact with the body structure at this point it ought to be possible to have a bass built with this tube moved to improve access.



The section holding the pickup and bridge is bolted to the neck at this point, the barest minimum structure required to hold a P-style pickup and the bridge assembly. The bridge is part where this instruments shows its roots in engineering rather than traditional lutherie most. It consists of four aluminium blocks each with a slotted bolt acting as the saddle. This is a similar mechanism to that of the early Lightwave bass bridges where the strings have to be removed from the saddle in order to adjust the action. It is easier to this bass than on the Lightwave but only slightly. Intonation adjustments are made by slackening off an allen bolt on by the E string saddle which pushes the 4 saddles together holding them in place. With the bolt undone it is possible to slide the saddle blocks forward and backwards. This is probably the crudest part of the instrument and where a more traditional style bridge might be easier to deal with. However it is also the main point of contact between the neck assembly and the body and it might require the mass to properly transfer the string tension down to hold the two parts together.



The pickup wires emerge (unscreened) beneath the bridge before disappearing into the control section. Here there is a simple passive volume and tone arrangement and a barrel output jack socket. There's not really much room in the control cavity for anything else - certainly you couldn't get an active circuit in there.

So what is it like to play? well it takes a little getting used to . Balance is good, but the body is longer than a traditional bass and the increased distance between the bridge and the end of the body means that if you're not careful you can find yourself playing much closer to the bridge than you wanted to. The neck is very slim and fast, yes it can feel cold, but if you're used to aluminium-necked instruments it's no worse than a Kramer. Sound-wise it's clear and bright. Definitely Kramer DMZ territory, although maybe not quite as much bottom end. Could probably do with a better pickup than the generic P-pup that it comes fitted as standard, but that's something I'll be investigating shortly.

I've been having a lot of fun playing this, plus I think it looks fantastic. Probably not the right bass for your typical pub band. I'm getting the urge to write some techno-industrial-metal....

[Wil]

I actually really like that. Even if you could hang your pants to dry on it. Very interesting concept isolating the string tension from the neck, although I wonder what effect that has on sustain?

[Shockwave]

[quote name='Wil' post='334106' date='Nov 21 2008, 09:12 PM']I actually really like that. Even if you could hang your pants to dry on it. Very interesting concept isolating the string tension from the neck, although I wonder what effect that has on sustain?[/quote]

Looks pretty steampunk in fact! (If he'd let it rust)

Yet again mate one of your basses has made me drool

[Prosebass]

Interesting way of doing away with a trussrod . The top half looks quite elegant but the bottom certainly doesn't to me.
As we were discussing in another thread, is it a case of finding a different way of doing something just for the sake of it rather than there being a need ?
I fully understand the mechanics of how they keep the neck straight as the way it is designed is supposed to put no pull on the neck. Does it work in practice ? (hope so they have a patent on it )
The way I see it is that unless the heel of the neck is pivoted any flex in the skeleton will be transmitted through the ball and socket and cause the neck to flex ? or is the skeleton totally rigid ?

[bremen]

Does it stay in tune as it warms up?

[BigRedX]

[quote name='Prosebass' post='334113' date='Nov 21 2008, 09:34 PM']Interesting way of doing away with a trussrod . The top half looks quite elegant but the bottom certainly doesn't to me.
As we were discussing in another thread, is it a case of finding a different way of doing something just for the sake of it rather than there being a need ?
I fully understand the mechanics of how they keep the neck straight as the way it is designed is supposed to put no pull on the neck. Does it work in practice ? (hope so they have a patent on it )
The way I see it is that unless the heel of the neck is pivoted any flex in the skeleton will be transmitted through the ball and socket and cause the neck to flex ? or is the skeleton totally rigid ?[/quote]

It's definitely one of those things were you won't 100% get how it works until you actually have the instrument in your hands. The ball and socket joint behind the nut holds the neck in position relative to the string anchor which is attached to the arm. At the other end of the neck the bridge simply rests on a plate that passes underneath it. The bottom of the bridge is radiused (have a look at the third photo), so the neck/bridge assembly pivots at both points but is also able to move forwards and backwards in relation to the body at the bridge point of contact. The body/arm assembly flexes quite a bit as you tune up until you reach equilibrium - similar to the way a guitar vibrato system interacts - but all that happens is that the bridge moves very slightly closer to the machine heads on the supporting plate. I would imagine that if I broke a string on this bass the others would go horrendously out of tune, but that's something I'll live with.

The advantage is that the neck can be very slim and so long as it doesn't easily flex by itself could be made out of any material, other aluminium necked basses have quite chunky necks like the Kramers or a truss-rod system like the Vaccaros and the Hartke bass I posted a while back. The T sectgion with wood inserts works very well although it could be a little more elegant.

Having played this bass a while now there are things I'd consider changing if I was going to have one custom made for me. The body needs to be shorter and it would definitely benefit from a more conventional headless tuning system maybe something like that fitted on Status basses? In the mean time I'll enjoy this fairly unique bass (I only know of a couple of others in existence - though I'm sure there's a few more out there) for what it is.

[Prosebass]

[quote name='BigRedX' post='334123' date='Nov 21 2008, 09:58 PM']It's definitely one of those things were you won't 100% get how it works until you actually have the instrument in your hands. The ball and socket joint behind the nut holds the neck in position relative to the string anchor which is attached to the arm. At the other end of the neck the bridge simply rests on a plate that passes underneath it. The bottom of the bridge is radiused (have a look at the third photo), so the neck/bridge assembly pivots at both points but is also able to move forwards and backwards in relation to the body at the bridge point of contact.[/quote]

That exactly what I meant when I said the neck heel needed to pivot but they have gone one better and put the pivot under the bridge so there will be no neck flex at all. If the skeleton flexes it just lifts the whole neck / body part which pivots at the bridge. So worst case scenario is just an adjustment in string height. Very clever engineering.

[mathewsanchez]

That's not a bass, thats a car engine!

[BigRedX]

Not even that. The neck assembly extends from the nut to the bridge so the string height/action is completely unaffected by the string tension. Even though it's in two pieces - the neck itself and the plate holding the pickup and the bridge the strings don't but any pressure on the joint, they simply push down at the nut holding it in place at the ball and socket joint and down at the bridge holding it against the body there.

On the question of tuning stability with regard to temperature, it seems no different to any of my other more conventionally constructed basses. In fact just checking it now after a week of playing since I last tuned it (although it hasn't left the house yet) the E string was very slightly flat, which was only noticeable using the Peterson Stroborack tuner.

[wizbat]

I,ve liked these for quite a while, congrats on getting such a cool bass.

[Stingray5]

Veeeery interesting!
What's the weight of this bass?
And how does it feel physically against your body when playing?

[GremlinAndy]

It's an *interesting* bass. I think it would look great relic'd as if it was made of iron. Lot's of rusty dark browns, and bright orange bloom in the corners. Wicked!

[budget bassist]

Hmm, the more i look at it, the more i like it!

[bassmanady]

I would hang this on my studio wall as a piece of art...very much like it..Reminds me of a Roland bass in design(i think)that has a supporting arm

[wizbat]

[quote name='bassmanady' post='334363' date='Nov 22 2008, 12:44 PM']I would hang this on my studio wall as a piece of art...very much like it..Reminds me of a Roland bass in design(i think)that has a supporting arm[/quote]


you mean the G77.

[WarPig]

i like!