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white_cloud
Intermediate Member
Username: white_cloud

Post Number: 174
Registered: 11-2007
Posted on Sunday, January 06, 2008 - 6:30 am:   Edit Post

Hey there Alembic folk,
at the risk of sounding like Im stupid or something I was thinking back to when I owned a Vigier graphite necked passion bass. It had no truss rod fitted as at the time, the unforgetable 1980's, everyone was heralding graphite as a miracle guitar material that would "never ever ever ever move" and be totally stable until the end of time!

I have noticed now that companies like Status etc are fitting all of their modern bass necks with truss rods..am I missing something here? I was under the impression that carbon graphite was extremely stiff..so how can a truss rod adjust such a material?

Obviously I have moved away from graphite and back to good old timber, but I just dont get it all the same??

Could someone explain this to me or else it will keep me awake at night:-)
keith_h
Senior Member
Username: keith_h

Post Number: 931
Registered: 2-2005
Posted on Sunday, January 06, 2008 - 7:54 am:   Edit Post

It's easy to answser. ;-)
While graphite is more stable than wood at can and does change with conditions. Also not everyone likes the same relief which is set when the neck is made. The truss rods resolve both problems.

I think the 80's graphite statements are just another case of hyping of a new material before all of its characteristics were really known.

Keith
white_cloud
Intermediate Member
Username: white_cloud

Post Number: 175
Registered: 11-2007
Posted on Sunday, January 06, 2008 - 8:01 am:   Edit Post

Thanks Keith.

Therefore anyone with a non-truss rod graphite neck (who, like me at the time, bought such a bass to avoid neck trouble) could end up with a warped neck and no means of adjusting it!!!!!

That is really scary:-(
bsee
Senior Member
Username: bsee

Post Number: 1855
Registered: 3-2004
Posted on Sunday, January 06, 2008 - 9:31 am:   Edit Post

Never seem a graphite neck move on its own. Of course, all "graphite" necks aren't made with the same material or strength. Graphite strips can be added to a wood neck for added stability, and those certainly move with the weather. I would think the only reason to have a truss rod in a true graphite neck is to control the relief.
bassman10096
Senior Member
Username: bassman10096

Post Number: 1054
Registered: 7-2003
Posted on Sunday, January 06, 2008 - 1:05 pm:   Edit Post

I'll echo Bob and Keith. I've never heard of a graphite neck warping in the sense that wood can (and does). Mostly, the repair work I've heard of has been modification to change relief from the manufactured arc of the neck.
Bill (the other one)
s_wood
Advanced Member
Username: s_wood

Post Number: 258
Registered: 5-2002
Posted on Sunday, January 06, 2008 - 7:57 pm:   Edit Post

Graphite necks will move, and anyone who says that they don't or can't is flat-out wrong. I had a Modulus Q5 a few years ago...one of the older ones without a truss rod. After changing strings from an unknown brand to DR HiBeams, the bass developed a pretty bad backbow and was unplayable. I called Modulus, thinking that I would need a new neck. I described the problem to their tech over the phone, and he replied by asking me if I was using DR's. When I said "yes," he told me to throw another brand on the bass and assured me that the problem would go away. I thought he was either lying or crazy, but I did what he suggested and put a set of GHS Bass Boomers on the bass. Within 2 weeks the bass was back in perfect relief. I have since learned that DR HiBeams, which are great strings IMHO, have a much lower tension than most other roundwounds of a comparable gauge.
Bottom line: graphite necks move.
bassman10096
Senior Member
Username: bassman10096

Post Number: 1055
Registered: 7-2003
Posted on Sunday, January 06, 2008 - 8:15 pm:   Edit Post

Interesting. I guess TI flats would be a problem as well. I owned a Modulus Genesis neck for a couple of years. Despite the fact that it is something of a hybrid between graphite (which bears all the weight) and wood, it never moved - regardless of temp, humidity, differing string tensions. It did have a trussrod, which I found handy occasionally when I wanted to vary the action dramatically. Personally, I though graphite seems more predictable than most materials, I doubt I'd want one without a t-rod.
white_cloud
Intermediate Member
Username: white_cloud

Post Number: 176
Registered: 11-2007
Posted on Monday, January 07, 2008 - 3:57 am:   Edit Post

I guess the morale of this story is dont buy a non-truss rod graphite necked bass!

It seems strange to me that so many high end graphite basses were manufactured by extremely well known companies (status, steinberger, zon etc) with this major flaw! I for one was, at the time, sold on this "miracle" material. Im just glad now that I sold the Vigier graphite (I needed the money back at the time and was real sad to see her go then!)

Its also crazy to think that a different brand of string would affect a "indestructable" graphite neck in such a major way.

I recently read an article about a buzzard bass made for John Entwhistle by the English company Status entirely from carbon fibre. Apparantly one day the instrument for no reason just totally shattered!

I think that there is a lot to be said for wood!
John.
bigredbass
Senior Member
Username: bigredbass

Post Number: 1264
Registered: 9-2002
Posted on Monday, January 07, 2008 - 11:24 am:   Edit Post

If I remember this correctly (DFung, forgive me if I'm wrong), graphite necks/instruments are thermoplastic, NOT thermoelastic: In other words, there's no such thing as a neck heat-bend on a graphite neck. So evidently, they were designed against a certain range of tensions, which the DR's must have fallen outside of.

The hell with it . . . I just like wood better. The structural and sonic anomalies just add to the mystery. Though the Steinberger I tried was eerie in that EVERY note sounded exactly the same on any fret and any string.

J o e y
keith_h
Senior Member
Username: keith_h

Post Number: 932
Registered: 2-2005
Posted on Monday, January 07, 2008 - 11:51 am:   Edit Post

Joey,
You are correct about the old necks without truss rods. They are created with a certain relief calculated for a certain tension. The only way to change that to the best of my knowledge is to plane the finger board or via the fret heights.

Keith
white_cloud
Intermediate Member
Username: white_cloud

Post Number: 185
Registered: 11-2007
Posted on Monday, January 07, 2008 - 1:01 pm:   Edit Post

Plane a carbon fibre neck....Whoa! I wouldnt like that particular task!

There is a real joy in using a razor sharp plane on a nice piece of timber, but planing graphite must be a horrible chore:-(
bassjigga
Advanced Member
Username: bassjigga

Post Number: 281
Registered: 8-2005
Posted on Monday, January 07, 2008 - 3:02 pm:   Edit Post

I have a Zon with no truss rod. So far no problem. Of course it's only like 3-4 years old.
keith_h
Senior Member
Username: keith_h

Post Number: 934
Registered: 2-2005
Posted on Monday, January 07, 2008 - 3:17 pm:   Edit Post

Maybe plane is not the correct word. I probably should have said machine (what type I leave up to the imagination). As I recall the fretboard is typically phenolic or something else other than graphite.

Keith
edwin
Advanced Member
Username: edwin

Post Number: 272
Registered: 5-2002
Posted on Monday, January 07, 2008 - 3:30 pm:   Edit Post

I have a '91 Modulus 6 string neck with no truss rod and it's been fine. I use DR Sunbeams, which are lower tension than the High Beams and it sits perfectly with a light guage (30-120). I have tried different strings and they all changed the relief in different ways. The Sunbeams happily are great strings, sound great, last forever and supply the perfect amount of relief.

I guess I'm just lucky because all other Modulus necks feel like clubs to me. This one is nice and flat. I'd be really bummed if anything ever happened to it.

Edwin
s_wood
Advanced Member
Username: s_wood

Post Number: 259
Registered: 5-2002
Posted on Monday, January 07, 2008 - 8:09 pm:   Edit Post

One other thing: graphite necks sound quite different than wood ones. To my ears, the difference is about the same order of magnitude as the difference in tone between a maple neck and a mahogany one. That's not a bad thing, but it is a factor to be considered. You may prefer the tone of graphite, or you may not care. The point is that you might hate it, too.

(Message edited by s_wood on January 08, 2008)
bsee
Senior Member
Username: bsee

Post Number: 1856
Registered: 3-2004
Posted on Monday, January 07, 2008 - 8:33 pm:   Edit Post

It's also true that different constructions of graphite sound different. I think the Modulus necks, especially when they made them neck-thru, sound sterile. You might as well play a block of granite. The bolt-on versions are a little better. On the other hand, Joe Zon's graphite neck Sonus bass sounds very much like a maple-boarded Jazz bass to my ears.

Between the different neck constructions, ways of mating them to bodies, and wood constructions to which they are attached, I think it's unfair to generalize as thoroughly as Steve did here.

As far as graphite necks moving, I believe they are susceptible to changes in string pressure, but not the weather. That's different from wood necks which will move with either.

The Zon fretboards are a composite of wood and other materials. Again, I don't think you can generalize as different manufacturers build differently.
dfung60
Advanced Member
Username: dfung60

Post Number: 293
Registered: 5-2002
Posted on Monday, January 07, 2008 - 11:09 pm:   Edit Post

Normally, I burst in on the graphite discussions earlier, but have been swamped lately!

As some of you long-time viewers already know, I'm a big Modulus fan and have been close friends with Geoff Gould who developed the original Modulus neck in conjunction with Alembic for many years now. So, we've chattered about why things were done the way they were many times in the past.

The interesting thing about building things out of composite materials is that you can engineer the characteristics of the final piece fairly precisely and repeatably. You'd have a hard time building a one piece wood neck that had specific stiffness or resonant frequency. You can get closer by laminating the neck, since the layers in opposition can counteract some of the natural irregularities in the wood. With something like a graphite neck, you can build in a very specific stiffness and you can control where the stiffness is directed. You see this to a greater extent in composite stuff like bike frames or golf club shafts, where they can engineer flex in in one direction and stiffness in a different direction.

When Geoff first got the idea of building a graphite bass neck, he was working at Ford Aerospace in Palo Alto, CA as a technician and composites fabricator. He was making satellite parts, totally cutting edge stuff at the time. These sorts of applications are totally weight-conscious - lifting a payload was monumentally expensive and very limited, so if you couldn't hit a weight target, you just couldn't do that mission. The strength of engineered graphite vs. steel, aluminum, or titanium was so much greater that they could use a lot less material for the same strength.

This is where the idea for the Modulus neck came from. Geoff saw Phil Lesh battling neck dive at a Dead show and thought that a lighter-weight graphite neck would solve the problem. He ended up talking with Alembic who built the first instruments with graphite necks, and the rest was history.

The lack of a trussrod in the original Modulus design was intentional on Geoff's part. From a purist's standpoint, he wanted the entire tension of the string, from end to end, to be borne only by graphite. The graphite material he used was exactly the same stuff that he was buiding satellite parts and Indy car tubs from, a graphite fabric that was impregnated with epoxy resin. Sheets of the pre-preg were cut and laid in a mold which was then cooked under heat and pressure in a giant autoclave until the resin cured and locked the graphite fibers into a solid matrix. The pre-preg fabric is unidirectional - the fibers all run parallel to each other - so you can engineer the performance of the parts by adjusting the direction that the grain of the graphite fibers and overlapping them in different directions. The material is thermoset, which means that the heat changes the material. The fabric is flexible before it's cooked, but after the curing reaction it is pretty impervious to heat and humidity. This is different than a thermoplastic material which is molded to a shape under heat, but will change again if you re-heat it later.

Even today, Modulus and Status necks are built using this process (Vigier was like this too back when they had graphite necks). Modulus necks are multi-piece assemblies which are laid up in molds. Status instruments are made by wrapping the pre-preg around a styrofoam core, basically the same process that you use to make surfboards. The Steinberger and Moses necks are made with a different process, where the neck is poured from a liquid resin around a graphite "backbone". The latter necks gain strength and stiffness from the backbone, but the structural characteristics aren't as controllable as the monocoque structure of Modulus necks (of course, the Steinberger and Moses necks are poured from a uniform material, so there is less variation than wood).

The resulting neck in a Modulus is really strong and stiff relative to wood, but still flexes under string tension, which it was intended to do. You can make a super-strong neck that doesn't flex or deflect at all under string tension, but this requires use of a stronger and more expensive pre-preg fabric. If you handled a Modulus or Steinberger, you'll immediately notice that, if anything, it's heavier than a wood neck rather than lighter. That's because the neck could be engineered to flex to the proper position under tension using less exotic materials which were heavier.

The earliest Modulus necks were made of these super-strong fabrics. A couple of years ago, a very old six-string Quantum through-body appeared on eBay. It turned out that this instrument, the second or third Modulus-logo'ed bass had been stolen from Geoff's office years before. The seller (who had purchased the instrument at a pawn shop) returned the instrument to Geoff, who was surprised to find that this BEADGC bass had it's regular low-B strings on it but was tuned up a fourth like a guitar! It was actually still playable, although I would insist on safety goggles and a full face shield before I'd touch it myself. There's no way that a wood neck could handle that sort of tension. And yes, these very old Modulus necks defintitely have a different tone than the regular production.

If there's a sonic advantage to no trussrod, there's certainly a physical disadvantage which is that you can't easily fine tune the action for your playing style and desired strings. As has been mentioned above, if you want to modify the relief, it needs to be done via a very expert fret milling. Ultimately, this is why all the makers of composite necks today have trussrods. The latitude of change in these necks is much less than the trussrod would yield in a wood neck, but sufficient to tune for different strings and desired action.

This helps make the instruments more produceable as well. In the case of Modulus, the "secret recipe" of the materials and construction is carefully tuned so that the fretboard can be planed to dead level and frets installed dead level under no tension, then will pull into the desired target relief when strung up. Over time as the materials change, they need to adjust the fabrication instructions to compensate, and this slowed down production because transitional instruments needed to have additional fretwork before they could go out the door.

Incidentally, the fingerboard on Modulus, Status, and original Steinberger is phenolic, the very first composite material. The graphite is way too hard to be shaped into a playing surface (it will quickly dull regular tools). Geoff considered a wood fingerboard but was concerned that it might not be stable since wood can be very subject to expansion with humidity and heat. He ended up selecting phenolic because it's easy to work (pretty much the same as wood) and aesthetically he wanted the neck not to have any wood in it.

The graphite in a Modulus neck is fabricated in two pieces - a main molded U-shaped part that has the shape of the back of a guitar neck and a thick flat plate that it bonded on to the top of the U. Together they form a monocoque tube which structurally is stronger than a solid neck (and saves on expensive materials as well). The phenolic fingerboard is epoxied on top of the flat piece.

The individual pieces are REALLY strong and stable. If properly constructed they won't bend, twist, or warp over time. It turns out that that's actually the Achilles heel of the Modulus neck. The curved main part is cooked in a mold, then the open side of the "U" is milled with a carbide tool to be dead flat and the flat piece is bonded on top of that. The problem arises when the milling doesn't done properly. This can leave an internal tension in the neck assembly where the parts want to spring apart with only the epoxy bond holding them together. Ultimately, a neck like this can fail and split along the bond line. This is the dreaded "delamination" which is largely fatal for Modulus necks as it requires the neck to be completely disassembled, remilled, reassembled, refretted, etc. Even with perfectly machined parts, the epoxy bond line is actually not that strong relative to the neck pieces and can be compromised by heat or when an instrument takes a dive off the stand. I think most of the reports of "warped" necks are actually delaminations (actually, it is a warp that's causing this).

I don't think you can find a better sounding instrument that a Series bass with Modulus neck. But it's got to be a nightmare for both Alembic and Modulus. Unlike regular Modulus production (which is mostly bolt-ons), graphite Alembics were very rare, so there was much less opportunity to tune the neck recipe for easy setup. The threat of a delamination is bad enough on a bolt-on where you have to scrap the neck, but a nightmare on a through-body where it could potentially lead to a non-repairable instrument. For these rare instruments (by all accounts much less than 100 total), there was also some jockeying around about exactly how they were made - Modulus always fabricated the parts, but in some cases the neck assembly was done at Alembic (where they had less experience but could maintain more control) and some at Modulus (where they had more assembly experience but no insight into how the neck would be mated to the body).

I was fortunate to have a Series II graphite neck made back around 1987, probably one of the last. I have no issues with stability although the action was never quite to my liking out of the factory (insufficent relief). Years later, I had this corrected in a very expensive fret mill by the builder who did most of Modulus' custom shop work, but even with his level of experience, it was hard to convince him to take on the job as he was concerned about disturbing the side LEDs in the event that he had to remove a fret. He didn't have to and it all worked out OK for my bass in the end though.

The fab process of graphite necks is so radically different than the woodworking that goes into a wood-necked Alembic, that it's not suprising that it's not offered anymore. Not only is it hard to manufacture, but you lose the ability to customize profile, scale length, and more.

David Fung
white_cloud
Intermediate Member
Username: white_cloud

Post Number: 186
Registered: 11-2007
Posted on Tuesday, January 08, 2008 - 1:18 am:   Edit Post

Thanks for that David, that was extremely interesting and has fully replaced my lack of knowledge/curiosity with a real understanding of this material!

I always loved the sound of graphite necked instruments. When I bought my Vigier ( 1980's) I actually had to choose between that or a top of the range Warwick streamer (a relatively new kid on the block in the world of bass.) After playing both extensively there was no choice for me..the Graphite Vigier sound was on a different level altogether!

In a way, it is nice to know that it is out there somewhere still sounding great...and with, in all probability, no neck woes!
funkyjazzjunky
Junior
Username: funkyjazzjunky

Post Number: 31
Registered: 5-2007
Posted on Tuesday, January 08, 2008 - 6:47 am:   Edit Post

Thank you David,

Two quick questions:

What is the differnce between Carbon Fiber neck and Graphite neck?

What about heat/sun induced expansion with graphite?
artswork99
Advanced Member
Username: artswork99

Post Number: 255
Registered: 7-2007
Posted on Tuesday, January 08, 2008 - 8:58 am:   Edit Post

Talking about no truss and graphite lets mention another bass here. The Hyak bass neck uses both wood and graphite and does not have a truss rod (I wish it did). I know that the Alembic factory has, at one time, put a truss into "Robert's Hyak". I'd love to have that done someday to mine. The bass has been well cared for over the years and fortunately the neck is in excellent condition. I can still do a great setup but the relief is all based on string tension. I am in the same place David was with his Series II - the action has never quite been where I want it.
funkyjazzjunky
Junior
Username: funkyjazzjunky

Post Number: 32
Registered: 5-2007
Posted on Tuesday, January 08, 2008 - 2:23 pm:   Edit Post

Thank you David,

Two quick questions:

What is the differnce between Carbon Fiber neck and Graphite neck?

What about heat/sun induced expansion with graphite?
dfung60
Advanced Member
Username: dfung60

Post Number: 294
Registered: 5-2002
Posted on Tuesday, January 08, 2008 - 2:56 pm:   Edit Post

Carbon fiber = graphite in this case. Graphite is the name for a particular form of carbon where the atoms are stacked up in sheets (that's how pencils write - the graphite sheets in the lead slide off onto the paper leaving a mark). Diamonds are also carbon with a different crystalline arrangement.

The carbon fibers are created from graphite which is why you see both terms.

Most people are familiar with the woven black checkerboard appearance of graphite items, like on the dashboard of your Ferrari (note, I didn't say "my Ferrari"). The graphite fabric used in a Modulus neck has the fibers aligned side by side and is super-strong doesn't look all that interesting. The surface that you see of a Modulus neck (and, I think that Ferrari dashboard) is actually a cosmetic layer that's there for a nice appearance rather than for structural reasons. Modulus has had a number of different surface finishes over time including different weave patterns, checkerboards and crystals. Since the 80's they've pretty much always had a sort of big polygon shape on the back of the neck. This is the linear graphite material cut up into angular pieces and laid into the mold before the structural pieces.

Once you've cooked and cured the graphite item, there's very little thermal expansion, even in direct sun (certainly less than any wood or metal). A Modulus neck is made of two pieces of graphite though, so there may be some differential expansion when one piece is heated and the other isn't. Again, this is pretty stressful on the glue joint.

When you want to make a wood neck, you can simply plane off any wood you don't want to reshape the neck. With graphite necks, you need to make a wooden form that is similar to the shape of the final neck, then a mold needs to be created, and the neck materials are placed in the mold to fab a neck. If you don't like the resultant neck profile, you really need to go back and remake the mold as it's pretty hard to cut or sand the cured graphite parts. Each different neck configuration - short, medium, long, extra-long scales, 4-, 5-, and 6-string necks each need to have their own mold. The molds are actually made of graphite as well. If you made the mold of any other material, the heat of cooking the necks would cause the mold to expand differently and you'd end up with a warped neck.

David Fung
byoung
Senior Member
Username: byoung

Post Number: 899
Registered: 12-2004
Posted on Tuesday, January 08, 2008 - 5:45 pm:   Edit Post

David,

I've always wondered-- I know that an autoclave (heat + pressure during curing) is the "right way" (i.e. most professionals, especially at the high end/non-cosmetic do it this way) to cure CF parts.

However, after seeing a bunch of vacuum bagging layups, I've wondered if something semi-structural, like a guitar neck (or guitar case, for that matter) would be eligible for this type of layup. It would be interesting, since it could drive the cost and prototyping/change timeframe down significantly, but more importantly open things up to us amateurs.

Thoughts?

Bradley
dfung60
Advanced Member
Username: dfung60

Post Number: 295
Registered: 5-2002
Posted on Tuesday, January 08, 2008 - 8:44 pm:   Edit Post

At Modulus, the mold fixture with the laid-up pre-preg is all inside a vacuum bag that has pressure fittings and all. The autoclave pressure is much higher than the vacuum bag though (I don't really know what the purpose of the bag is). The autoclave they use is big - it's a cylindrical thing that's probably 10' feet long and at least 4' in diameter. The length of the neck is the determining factor and they run only 2-3 necks at a time. It's heated, but I seem to remember them saying that it's not any hotter than a cool oven (of course the pressure creates the effect of it being much higher).

In the two examples you cite (neck and case), the composite *is* the structural part, so I think it's a different situation than than a non-structural part like a pre-preg skin on top of a metal or plastic part.

The Steinberger and Moses-type construction, which is more of a cast resin structure is probably easier to do on a amateur basis. I don't know too much of the specifics of how Moses is made, but the Steinberger composite construction was the process that's used to make boat hulls.

David Fung
davehouck
Moderator
Username: davehouck

Post Number: 5966
Registered: 5-2002
Posted on Wednesday, January 09, 2008 - 7:50 am:   Edit Post

David; as always, thanks!
byoung
Senior Member
Username: byoung

Post Number: 902
Registered: 12-2004
Posted on Wednesday, January 09, 2008 - 8:09 am:   Edit Post

David,

My thinking would be that the vacuum is there to pull the resin through the fiber without bubbles. Vacuum bagging is all about getting the resin into the fiber, and the autoclave is for curing.

Roll-on or brushed layouts almost always have bubbles in them, and they are bad cosmetically and structurally.
rogertvr
Senior Member
Username: rogertvr

Post Number: 417
Registered: 1-2003
Posted on Friday, January 11, 2008 - 6:10 am:   Edit Post

"Graphite necks will move, and anyone who says that they don't or can't is flat-out wrong."

Absolutely spot-on. Both of my Status Graphite Buzzards and my Stealth all require a quarter turn of their respective truss rods in the autumn, and a quarter turn in the opposite direction in the spring. That was one of the first things Rob Green at Status has told me on the occasions I purchased these basses. The rest of the time though, they're completely stable.

I'm not sure what the significance of autumn and spring is though, but I can almost predict the day they will move on!
rogertvr
Senior Member
Username: rogertvr

Post Number: 418
Registered: 1-2003
Posted on Friday, January 11, 2008 - 6:18 am:   Edit Post

"I recently read an article about a buzzard bass made for John Entwhistle by the English company Status entirely from carbon fibre. Apparantly one day the instrument for no reason just totally shattered!"

That was one of the two prototype instruments that was made for John by Status Graphite. I believe neither of them had serial numbers and one survives - the other one failed.

When I ordered my Buzzard, I did ask Rob Green about the failure and he told me that there was a problem with the failed prototype instrument and that the problem had been resolved for production models.
adriaan
Senior Member
Username: adriaan

Post Number: 1752
Registered: 6-2002
Posted on Friday, January 11, 2008 - 6:55 am:   Edit Post

Roger, could it be that a graphite neck with a truss rod is more susceptible to those changes, than a graphite neck without one?

I also remember a thread here a while ago of a member who had a graphite neck that turned unplayable on a very hot day, in direct sunlight.

(Message edited by adriaan on January 11, 2008)
lbpesq
Senior Member
Username: lbpesq

Post Number: 2851
Registered: 7-2004
Posted on Friday, January 11, 2008 - 7:11 am:   Edit Post

The Bond Electraglide was a guitar made in Scotland in 1984-85 - about 1400 total production. The entire guitar was made from carbon fiber, except the fingerboard which was anodized aluminum with "steps" instead of frets.

Bill, tgo
rogertvr
Senior Member
Username: rogertvr

Post Number: 419
Registered: 1-2003
Posted on Friday, January 11, 2008 - 7:18 am:   Edit Post

"Roger, could it be that a graphite neck with a truss rod is more susceptible to those changes, than a graphite neck without one?"

I don't know, Adriaan. I don't think I'd be too keen on any neck without a truss rod in it to be honest and I don't own one.
adriaan
Senior Member
Username: adriaan

Post Number: 1754
Registered: 6-2002
Posted on Friday, January 11, 2008 - 7:25 am:   Edit Post

Just thinking out loud!
white_cloud
Intermediate Member
Username: white_cloud

Post Number: 191
Registered: 11-2007
Posted on Friday, January 11, 2008 - 10:12 am:   Edit Post

There are an awful lot of graphite neck instruments out there without truss rods! Most made by such estimed people like Steinberger, Status, zon, Vigier etc.

It is sobering to think that in theory such a high quality basses could have a potentially problematic necks with no means of adjustment!
keith_h
Senior Member
Username: keith_h

Post Number: 939
Registered: 2-2005
Posted on Friday, January 11, 2008 - 1:55 pm:   Edit Post

Keep in mind we are not talking the same type of problems you see with wood. I would never expect the twists and warps you see with wood in a graphite neck. Also depending upon how you set your action you might not even notice a change in the neck relief.

As to why they can change, in addition to string tension I suspect interaction between the fretboard and neck. Depending upon the fretboard material I would expect it to heat and cool at a different rate than the graphite. I'm not a chemist or physicist but would not be surprised that this could cause changes to the neck relief even after the parts have reached the same temperature. If the fretboard were wood I would also expect humidity to have some involvement.

As has been mentioned not all folks like the relief the neck has been manufactured with. So a truss rod also helps here.

Keith
white_cloud
Intermediate Member
Username: white_cloud

Post Number: 192
Registered: 11-2007
Posted on Saturday, January 12, 2008 - 3:02 am:   Edit Post

Some very thorough and knowledgeable responses on this subject! Thanks folks:-)
dfung60
Advanced Member
Username: dfung60

Post Number: 298
Registered: 5-2002
Posted on Sunday, January 13, 2008 - 11:28 pm:   Edit Post

I'm surprised at the seasonal changes that rogertvr mentions with this Status basses, but that is what the truss rod is there for. With a wood neck instrument, the seasonal variation is attributable to the change in humidity that goes with the seasons for most of us.

For what it's worth, I have a Status Stealth headed 5-string of pretty recent vintage and haven't noticed any changes in action during the year (I live in Northern California though where seasonal change is pretty minimal). One thing I have noticed about the Status instruments is that the truss rod has much more prounounced effect than a Modulus with truss rod.

The Status construction uses pretty much the same materials and process as Modulus, but the necks are a true one-piece construction, where Modulus is two-piece. Modulus lays up the pre-preg fabric in a mold then bonds two pieces together to form a monocoque structure. It looks like the Status stuff is done by creating a foam core and wrapping pre-preg fabric around that core. It's probably easier to tool up a mold to make foam cores than one that directly forms the neck, and another plus of the Status process would be that you should be able to hand cut any shape in the foam buck rather than have to fabricate a mold. I'm pretty sure this is how the German Basslab basses are made, many with really crazy shapes, but I haven't ever had a chance to look inside one of these.

There are a couple of Status models where there is a wood neck with a cosmetic graphite skin on top. I think this is how the Kingbass is made, but could be wrong about that.

There's a HUGE difference in expansion of the graphite neck and phenolic fingerboard of a Modulus or Status bass. The graphite is very stable, the phenolic has a lot more expansion and is very similar to wood. The phenolic material is actually formed out of sheets of something like kraft paper that is permeated with resin and squeezed under pressure. The end grain of the paper is exposed to the environment and will swell with humidity.

I have the original fingerboard of a Modulus of mine (for many years my #1 bass) that delaminated and had to be disassembled and reconstructed by the factory. The phenolic fingerboard was stripped from the graphite underlayment (the thick flat graphite plate that is bonded on the back of the neck to form the graphite monocoque, or tube structure), so there's a coating of epoxy on one side still. The neck was defretted first, so the fret slots in the top are bare, but I've been suprised to see the fingerboard has developed a significant bow since it was liberated from the rest of the neck. Over the course of 4-5 years, the raw fingerboard has developed a bow of almost 2.5"(!). A little of that is probably from the fret slots, but I think most of that must be the differential absorbtion of the raw phenolic vs. the side that has epoxy on it. I don't think a wood fingerboard would warp that much.

I think this is actually part of the reason that the glue joint in this neck failed. This is actually a bit of a design weakeness in early Modulus necks. The gluing surface between the main neck piece and underlayment are the two milled flats, each of which is the thickness of the graphite structure. Since these necks are laid up by hand, this can vary from neck to neck, and sometimes the width of the gluing surface can be quite thin - less than 1/4". Impacts on the neck, or a hot trunk can weaken that narrow joint pretty easily. The phenolic fingerboard on the other hand is bonded by it's full width to the underlayment - a much stronger bond. If the fingerboard is applying spring force to the underlayment, that would stress the critical glue joint even more. By the mid-80's they were laying more material in the region of the nut so there would be a larger gluing surface.

David Fung
white_cloud
Advanced Member
Username: white_cloud

Post Number: 201
Registered: 11-2007
Posted on Monday, January 14, 2008 - 4:46 am:   Edit Post

What bass do you prefer David, the Modulus or the Status? John.
dfung60
Advanced Member
Username: dfung60

Post Number: 299
Registered: 5-2002
Posted on Monday, January 14, 2008 - 10:17 pm:   Edit Post

John -

The Modulus and Status basses are both excellent instruments. I have accumulated many, many Modulus instruments over the years vs. just one Status. I'm close friends with Geoff Gould who started Modulus which is part of the reason/"problem". On the other hand, Status instruments are very rare birds here in the US. If I had to pick one, I would opt for the Modulus as it's a better balance of traditional tone with composite characteristics (really extended low end, long sustain).

I had been looking for a Status S2 for a number of years, which is a neck-through graphite-necked instrument with a wood body. I had only been able to find bolt-on Status basses in my casual looking around. The Stealth popped up through a mutual acquaintence at a NAMM show. One of the US Status dealers was ending his distributorship and sold the Stealth to me for a very good price. The Stealth is a one-piece, all-graphite bass (neck and body). It's very light and tonally quite different than the S2, probably not in a really positive way. I have a couple of Modulus Flight Monocoque basses which are also one-piece all-graphite basses (more in a Steinberger style, headless with a compact body) which are somewhat similar in tone to the Stealth.

The problem with these hollow, all-graphite instruments is that they have a somewhat thin tone with very little punch.

I would generally characterize the Status instruments as slightly brigher than typical Modulus instruments. The early Modulus basses, which used a stiffer and lighter construction have tone that's closer to Status.

I am lucky to have an Alembic Series II with Modulus neck. It's just awesome - the combination of the Modulus neck with the Alembic electronics is hard to beat, although this is not a very traditional tone.

One of the most notable composite instruments are the Steinberger basses. I've got a bunch of these as well. Although the compact bodied models are all composite, they're tonally quite different than the Modulus or Status, probably because it's a totally different style of construction and materials. They have a lot of punch and long sustain, but interestingly, not that much low end. They're great instruments, but quite different and distinctive.

I also have a Parker Fly bass, which is a very light wood neck with a graphite overlay. It's a very different instrument leaning more toward the highs than the lows (it's actually very similar to the Stealth). It's a very interesting bass to observe from the standpoint of construction as almost everything in the instrument is different or unusual (laminated wood body, unusual shape and electronics, tangless frets, etc.).

David Fung
0vid
Intermediate Member
Username: 0vid

Post Number: 114
Registered: 4-2003
Posted on Tuesday, January 15, 2008 - 2:24 am:   Edit Post

Thanks David for the illumination. I still regret humming ad hawing over a Series one graphite lefty when one turned up for sale - the seller didn't have the DSR 5 so I stalled and it eventually went to someone else.

My main bass is a status bolt on headless on a body I built with Alembic guts. It virtually never goes out of tune. It is a pre truss rod one. Thankfully I am happy with the relief. You can see the diamond weave on the status and it is much nicer to look at.

I also have a Moses necked bass. It is a J neck on a P body. It is cast resin and appears a dull black. If you want to see a 'graphite neck' FLEX, string up a Moses.....the strings rub against the fingerboard until you are in tune to standard pitch. You can see the peghead flex too. I think my moses has a truss rod... and I remember when I set up the instrument I was thinking "is this going to work?" It did and plays fine. But the Status neck to me is much better produced. If I can convince Rob Green to make lefty replacement Fender necks I'd get them for sure (though it would be nice if they offered a choice of frets).

I should have had another Moses neck, a fretless lefty by now for a custom lefty body with Fatboys, but it has been lost between Royal Mail and USPS for 4 months now and that, as the saying goes, is another story altogether.
white_cloud
Advanced Member
Username: white_cloud

Post Number: 207
Registered: 11-2007
Posted on Tuesday, January 15, 2008 - 4:56 am:   Edit Post

Wow David, what an incredible collection..and a very cool answer!

The only Graphite necked bass I ever owned was a vigier passion. It was a neck through and had a bewildering tonal capacity! It was used on a couple of albums by the Scottish band "Hue and cry" (if I remember correcly I traded my vintage 70's jazz for it.) I hit financial trouble at the end of the eighties and it had to go. It was one of the finest instruments that I had the pleasure of owning! I had a Wal custom around the same time, it was also incredible, but not as "user friendly" as the Vigier - i.e. the necks on Wals were hard for a lot of players (including me)to live with!

Im a great admirer of Status basses, but have never actually owned one. They are certainly common here in the UK ( Modulus basses certainly are not! ) and are very affordable! In fact I am without a backup bass for my Alembic at the moment and was toying with blowing my "Alembic no 2" fund on a bolt on status custom walnut model ( much much cheaper than even an Epic here ) Im not sure if I would live to regret this..choices choices!

I mean, with my luck I would probably buy the status then a cheap Epic would appear the next day and I would be thinking (not for the first time) what if??
lp75
New
Username: lp75

Post Number: 1
Registered: 1-2008
Posted on Friday, January 25, 2008 - 10:55 pm:   Edit Post

David,

Hi, I am new here.
I'd like your opinion here, and from what I have read, you may be more qualified than anyone I have ever heard on the subject of "old Modulus" basses.

Back in 1984, I was witness to Phil Lesh using his first Modulus 6-string instrument on stage with the GD. On into 1985, and his tone was - and still is - my ultimate "Nirvana" of bass tone.

I own a new Modulus Quantum, and am aware of the differences in these instruments. But I still seek that elusive TONE that was produces from the early graphite through-necks.

What hope do I have of ever obtaining an instrument that can get me there? I narrowly missed the opportunity to get a "production" TBX Q5 from 1991, and now I feel that I may never get another chance. Nobody is building such instruments - not even Jeff Gould. What can I do?

Thanks,
LP
dfung60
Advanced Member
Username: dfung60

Post Number: 302
Registered: 5-2002
Posted on Saturday, January 26, 2008 - 2:29 am:   Edit Post

LP -

Thanks for the kudos.

Having handled a lot of Modulus instruments, there are definitely big differences in sound between the very early production (70's through early 80's) and the instruments that were made after the mid-80's. There's a number of reasons for this, but it seems to me that there were changes in the materials and construction that led to changes in the tone too. The pre-polygon finish necks have an extended high end that's probably reflective of a stiffer grade of graphite pre-preg. Most of the polygon necks are darker sounding. The really early ones (crystal finish) sound the best to me, but they're also much more likely to fail.

By their nature, through-body Modulus basses sound different than bolt-ons. The bolt-ons already have more sustain in the bass and highs than a wood bass, and the through-bodies have even more - so much so that it almost sounds compressed to my ears, with a really high sustain level.

There's another difference I suspect is often in play. It's very difficult to build a through-body bass, relative to a bolt-on. Each step along the way is complicated because you're constantly handling a larger assembly which is a more difficult shape to work on. Obviously, there's greater risk if you make an error that you'll lose the entire bass.

As I mentioned earlier, Modulus necks are assembled by cutting pieces of mono-directional pre-preg and assembling them in the mold to engineer the strength and stiffness. On the regular production bolt-on necks, they make enough of them that they can tweak the "recipe" so that the neck will pull into proper relief under string tension. On unusual/custom instruments (all through-bodies were in this catagory), they sometimes would use a different, stiffer, and more expensive graphite fabric to make sure that there wouldn't be too much relief. This stiffer graphite was the same stuff that the earliest necks were made of. Because it doesn't flex as much, they often required more work to finish the fretwork, but these special instruments were going to require more work anyway.

I have a bunch of necks with the stiffer material, some of which were old instruments (a through-body Bassstar 4) and a couple of early 90's instruments that were built with this stuff because they were "odd" customs. One of them was a bolt-on 8-string bass that has the same neck shape as an M92 5-string, but in the stiffer graphite. It's the most amazing thing I've ever heard and quite different than a regular M92 (I've got one of those too).

The production of through-body basses was so disruptive to the normal production at Modulus that they pretty much stopped making them except for the occasional celebrity instrument after Geoff left. These days, Modulus has been running a very tight ship and I don't think they make any through-body instruments at all.

The good part is that Modulus instruments in the aftermarket aren't commanding stratospheric prices (just my luck!). Since they would be pretty much impossible to repair (Modulus definitely won't do that anymore), you do need to exercise caution when purchasing that you can get your hands on it before the sale is permanent.

In current production, I think the Status S2 Classic is actually pretty close to the old Modulus sound if you can find a through-body. I believe that the Status Empathy is pretty much the same model. The sound of the few Status basses that I've played is more reminiscent of the older Modulus than the current production.

David Fung
kilowatt
Member
Username: kilowatt

Post Number: 74
Registered: 12-2004
Posted on Saturday, January 26, 2008 - 6:57 am:   Edit Post

Lp,
Bass Cental actually has a 91 TBX for sale. I think Beaver was looking for $2400.00 for it. I am always looking out for the old TBX's, but I would prefer a different color than red. I missed one on e-Bay about 5 years ago that I believe had a coco-bola top on it. I should have grabbed it at the "Buy it now" price. Live and learn.

Regards,
Pete
lp75
New
Username: lp75

Post Number: 2
Registered: 1-2008
Posted on Sunday, January 27, 2008 - 12:31 am:   Edit Post

Thanks David.
I've been curious about the Status basses, but have yet to see or try one in person.

Before reading your posts, I was unaware of the different material types used on old Modulus necks, and I was unclear on the potential problems. You have cleared that up well.

I suppose I will just enjoy my Modulus (I had it modded by Mike Lull, and it sounds fantastic!) and keep an eye out for other graphite instruments.

My other thought lately is to save up the money to buy an Alembic 5 string with the filter electronics and those ebony neck lams - I have a strong suspicion one of those may make me forget about everything else.

Kilowatt: I just missed a '91 TBX 5 in December that I could have had for an even $2k - but narrowly lost out. I have been aware of that "toilet seat red" TBX at Bass Central for over a year, and it's just a bit too ugly!

LP
white_cloud
Advanced Member
Username: white_cloud

Post Number: 229
Registered: 11-2007
Posted on Sunday, January 27, 2008 - 2:41 am:   Edit Post

Staus basses are plentiful and reasonably affordable (much more so than an Alembic!) here in the UK!

There are various models/incarnations available, but the best ones are undoubtedly superb instruments!

The 100% graphite basses produced by Status are nice but Im always more impressed with the graphite /exotic wood instruments that they produce!

John.
kilowatt
Member
Username: kilowatt

Post Number: 75
Registered: 12-2004
Posted on Sunday, January 27, 2008 - 7:07 am:   Edit Post

"Toilet seat red". That description had me rolling on the floor! I thought the same thing. If the price was a little lower, you could always have it refinished.

Regards,
Pete

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