Non-traditional bass construction ideas

Discussion in 'Basses [DB]' started by Jeff Bollbach, Jan 24, 2003.

  1. Jeff Bollbach

    Jeff Bollbach Jeff Bollbach Luthier, Inc.

    Dec 12, 2001
    freeport, ny
    Recently, people have been becoming aware of some alternative approaches to bassmaking. Notably the removable and adjustable neck of James Hamm's basses and apparently Bob Ross is making basses with detachable necks and c-bouts. While I have not actually seen any of these basses I do have a pre-judgement[mostly negatory] about these approaches. But I am open to learning more. When I originally saw a single non-detailed pic of a Ross bass with a detachable c-bout I thought it ludicrous. Now, having seen his site i see that he appears to be doing work of note.
    Mostly I am concerned with the long run. What future problems may these instruments face regarding structure? Advantages/disadvantages?
  2. I've had one of Jim Ham's basses (I think it's one 'm', anyway) in my shop - his #4. It was an oddly proportioned instrument, built for a very small player. Sort of looked like an egg, to me. Leaving aside some differences in taste elsewhere, I looked some at his sliding neck. It seemed sort of cobbled together. There was ebony in there, and aluminum, and a titanium bolt or two.... I was only working on a new E-capo for the extension, so I didn't take the neck apart and cannot speak for the inner workings, but the impression I had was that this thing was not going to be very stable in the very long run. Just a feeling though, as there's no way to prove that. Besides the 'luthier' aspects I didn't like much, when I plunked on it and bowed it a bit the thing seemed weak, distant. Similar in tone and volume to a 179~ Lupot I had around for a while which had been brutally cut down and had suffered many questionable repairs. I've played more responsive Kays, frankly. But the player of Ham #4 was very happy, so maybe it's a fitting to the bassist kind of thing.
    The convenience and relatively inconspicuous appearance compared to having bridge adjusters was very apparent. Seemed a great boon to the travelling bassist. I heard he was considering retrofitting one of these to an old bass, but haven't heard anything since, so maybe he didn't do the butchery after all. Scary thought, to me. Still, a single allen key does the job, which is cool. Then again, a well made and fitted pair of wooden bridge adjusters can be adjusted at full pitch without any more tools that a few fingers. But for 'purists' who won't have the integrity of the bridge broken down for acoustical reasons, I suppose un-gluing the neck might be considered an option.
    I remember seeing a Double Bassist articl on a Bohemian bass with a bolted-on neck... the author of the article talked about the possibility that with shims one might actually shift the angle of the neck! And for travels around Europe in wagons, certainly a great advantage to be able to break out the neck.
    I saw the first one Jim made too, when Gary Karr did a master class here years ago. Same adjusteble neck, and still a smaller body, but more conventionally proportioned. Had a one-piece maple back! Beautiful wood. And as a few bassists have hinted to me since, Gary can make anything sound awesome. But at least one fella trying it said he couldn't make it sing at all. Another bassist, one having done a couple of his summer camps, said something pretty similar, and that that experience had put her off ordering one of the Ham basses. I've no idea if this has any connection to the sliding neck joint, but all that added weight, and the inevitably poorer vibratory connection. they couldn't help, could they?
  3. Jeff Bollbach

    Jeff Bollbach Jeff Bollbach Luthier, Inc.

    Dec 12, 2001
    freeport, ny
  4. Damon Rondeau

    Damon Rondeau Journeyman Clam Artist Supporting Member

    Nov 19, 2002
    Winnipeg, baby
    I'm always a little uneasy horning in on this luthier shop talk, 'cause I'm just a newbie dilettante in this area. On the other hand, 'cause I'm really just pleasing myself in this realm of activity, I'm free to try some of this crazy sh*t in a way maybe you guys aren't.

    In thinking about this topic, I think about how the bass works and how its design has evolved, and I ask myself what's missing from a functional point of view. What needs are unserved? What activities (necessary or not, but necessary is better) aren't enabled 'cause of the evolved design as we receive it today?

    It's a straw-grasping thing. It's a damn good evolved design.

    But, we see some intriguing thoughts being worked on. Neck adjustability. Easier access to the guts (I like that idea, it makes sense 'cause it would make life easier.)

    I think it would be interesting if anyone could just contribute some of these blue-sky what-if type ideas. Might turn on a light for someone.

    I was just checking out the web site of Dustin Art Williams (, who apparently is working with the aforementioned James Hamm out in Victoria. (Gerard, I'll bet you're familiar with all this stuff.) Anyway, in reading more about the Hamm work, I came across a ref to a "collet style" endpin assembly. I have no further detail than that, what it is, how it works, etc., but it sounds a bit intriguing. The tapered hole is a great idea but from a construction point of view maybe there's a better way that doesn't require the reamer. Not that I have anything in particular against the reamer, but it's a very sophisticated piece of tooling. Maybe things could be simpler is all I'm saying.

    Anyway, it's the sort of thing I'm thinking of. Ask what's missing, then see if it makes any sense to do something about it.

    And Jeff, what's long term? If they didn't exist, would you not build a flatback if you thought up the idea?
  5. arnoldschnitzer

    arnoldschnitzer AES Fine Instruments

    Feb 16, 2002
    Brewster, NY, USA
    Perhaps I'm more of a purist: I'm of the opinion that a well-fitted neck joint (wood-to-wood with good hide glue) is imperative to getting good tone and response from an instrument. Introducing metal and comosites and screws into this crucial area makes my knees weak...An area I'm interested in exploring is assymetrical design. Why not build uneven shoulders to allow good access without creating a whiny sound? The bass could certainly stand some changes in the area of ergonomics...

    BTW, on the subject of James Hamm: He makes his ribs of multiple layers of wood, which are glued and vacuum-pressed with silk in the middle. I suppose this is to help prevent cracking. But I worry about adding rigidity, which is the enemy of tone in a stringed instrument. Ergonomically, his design is very good, with small shoulders that facilitate getting around the bass. But I've yet to hear a narrow-shouldered bass that rumbles. I understand, though, that rumbling is not a sound Gary Karr or his devotees aspire to. In that case, the Hamm design may be perfect for its purpose.
  6. WOW! I had no idea Jim was laminating silk into the ribs these days! Last article I read the images (in the Strad, about 3 years ago maybe) portrayed a pretty normal set of maple ribs. The mould he used was a bit unconvertional, but that's it. I prefer the Cremonese-ish single layer mould, just a piece of good plywood cut to shape and carefully trimmed works fine for 'cello or bass ribs and blocks. And no full-depth rib mould bass I've yet seen has escaped a sort of flatness, or in the worst cases a concavity to the rib. The old style makes for a lovely, subtle swell when light bounces off the varnish. And if there's any convexity at all, methinks that echoes an internal concavity, meaning a rounder internal shaper overall, meaning more efficient reflection of sound...
    I intend to use linen to line the ribs of this bass, as I have done in several bass restorations where rib cracking was extreme. My 'cello is thus lined as well. Unbleached linen has lots of historical precedent in reinforcing bigger ribs, and saturated with hide glue, rubbed smooth, and sealed with a couple of light coats of shellac they seem stable and strong, and ascoustically reflective.
    I have asked a couple of players who have Hamm basses about the collet endpin mechanism. They said it's a bit sticky. Tolerances must be very close, and the inevitable accumulation of hand-guck and whatever (even on titanium) makes them so. The one I had on the bench was certainly not smooth. Sort of like a bigger version of the collet chuck for my little Taig lathe; needs a bang on the side to loosen the grip before adjusting it. But as it seems I'm somewhat out of toucch with how Jim's masses are made these days, he's probably got all that stuff sorted out by now.
  7. I've been using unbleached artist canvas for over 30 years and have been very satisfied with the results. I've never coated the canvas/hide glue with shellac or anything else. It work great without it. Actually, I would think that coating with shellac would take away one of the biggest pluses for using canvas or linen. That being ease of removal in the future. With just hide glue, all you need is a little hot water to remove the canvas. Add shellac and it becomes waterproof.
  8. Maybe y'all di'n't notice when I wrote 'light coats'? I mean really thin orange shellac, even gum lac, and not enough so there's a significant colour shift towards amber. My reason for this coating is to slow, slightly, the uptake and the release of moisture by the cloth/inner ribs, making for less dramatic rates of rib dimensional changes.
    Linen is the material of choice for me, and traditionally, because it is almost unique among natural fibres in being very hygroscopic, unlike cotton, besides being dramatically tougher. Linen is cool to the touch. This is because in a given surrounding humidic condition it always contains a slightly higher percentage of water. Directly bonding this moist cloth to the ribs prevents excessive drying of the ribs, which can lead to a lot of shrinkage cracks, especially nearer to the blocks where the cross-grain stresses are most in need of equalization. A coating of shellac, a very thin one, makes the interior surface water resistant, not waterproof. The differential between this and the more direct interface between cloth and maple, combined with the obvious moisture resistance of the outside varnish, mean that an hour or two in foggy weather or a long wait for a cab in the rain will not necessarily lead to extreme water uptake by the ribs. Likewise, if less helpful, in short stays in very dry rooms, or under excessively hot stage lights.
    The strength of linen is truly amazing besides. A very thin piece cannot me torn by any mere mortal, even with a little cut made to start the tear. I find cotton to be quite a lot weaker for the same weight, and since one of the aims in making instruments is to keep the weight down for better resonance, the thinner the ribs and the cloth the better.
    There's an Ontario maker named Chandler; I'm sure a few of you have seen his basses. Very economical, for a one-at-a-time bass of decent wood, and some fair work there. Not exactly my approach, to understate things, but he's very productive, enthusiastic, and his instruments have made for some happy bassists. His ribs are very thin. Press one, especially in the lower bouts, and watch in amazement how deeply your thumb distorts the rib. Such weakness would be fine if reinforced, thinly, with linen. As it is, I have already seen 3 rib repairs on these basses, and expect to see a lot more in years to come. Two so far were just minor ding cracks, touches against a chair or a step. The other was a stair railing, which when lightly crashed into while inside a good bag resulted in a knockout of several thin chunks of maple. Not much fun to repair, but I managed through a wedged opening in the oposite side rib/back juncture with rods, pokey bits of metal, and an extended glue brush. A few tiny cleats and a covering of linen made it just a little stronger than original, but barely heavier. My feeling is that if this bass had linen to begin with, the worst it would have suffered would likely be a single, short crack, something easily rubbed full of glue and left alone, with no risk of a 'step' and no need to clamp it even.
  9. I didn't mean for this to get into a discussion of canvas versus linen, but I will add that canvas has a long history of being used for repairs and reinforcement of violin family instruments. Stradivarius used canvas and that's good enough for me.

    Now back to my previous question. It seems to me that if makes no difference what so ever if the shellac coating makes the linen "water proof" or "water resistant". It is still going to make it more difficult to remove than one sans shellac.
  10. Damon Rondeau

    Damon Rondeau Journeyman Clam Artist Supporting Member

    Nov 19, 2002
    Winnipeg, baby
    Thought I'd try and link a few pix for the first time.

    Here's how David Rivinus dealt with the ergonomics of viola. It's his Pellagrina.
    front: [​IMG]
    back: [​IMG]

    I'd say that's asymmetrical.
  11. I guess that's one way to make a large viola without having too thick or too long. It looks like that tailpiece is more for show than for acoustics.
  12. Jeff Bollbach

    Jeff Bollbach Jeff Bollbach Luthier, Inc.

    Dec 12, 2001
    freeport, ny
    i saw that years ago and it still repulses me. I believe it was the Strad Magazine that ran an article about a handful of makers who were making assymetrical instruments. There wasn't a bass though-mebbe Arnold will be the first. I'm not against an assymetrical instrument-it's just that that Rivinus thing looks cancerous to me. But good one, Damon-Arnold mentioned assymetry and you gave it in spades. How did you get that pic to appear on the thread and not as a file?
  13. Damon Rondeau

    Damon Rondeau Journeyman Clam Artist Supporting Member

    Nov 19, 2002
    Winnipeg, baby
    ... yes, I posted without comment deliberately. It's kinda shocking and, well, ugly.

    His site ( has a design page where he talks about why it's shaped that way. There's a banked fingerboard on the thing in addition.

    The inline image thingy went like this:
    • right click on image and bring up properties
    • copy the URL for the image to clipboard
    • whip back over to TB edit page
    • hit that little IMG vB code doo-hickey
    • plop in the clipped URL

    I have no idea whether this is kosher rules-wise. Sue me or turn me off.
  14. Damon Rondeau

    Damon Rondeau Journeyman Clam Artist Supporting Member

    Nov 19, 2002
    Winnipeg, baby
    ... ya know, I just had another thought about the viola I just called ugly in public. Mebbe if you were a viola player looking down on that thing all those hours, and because of its design it wasn't twisting your body all to hell, well maybe you'd adjust your definition of ugly.


    It's meant to be played first. But it's an ugly child.
  15. Yeah, I'll 3rd or whatever it is the comment that it's pretty darn ugly for a viola. I like better the subtler asymmetries (sp?) Christophe Landon did some years back. They show a little more respect for proportions of a proper violin-family instrument, while allowing some better access here and there for the player.
    Regarding linen, again - sorry - I thought Antonio used linen for contralto violas and larger? That's what at least two separate accounts that I came across said. In one, it was clearly spelled out that he was using linen, and that in the 'violoncelli so reinforced the ribs had remained relatively uncracked for centuries, provided the linen was removed and replaced with similar material every century or so. But hey, what do I know? Maybe I chose to read the only two references that don't mention cotton! I have seen a bit of cotton used here and there, mostly in the form of woven 'webbing' cut into lengths and glued in without saturation. This has offended me as making a sort of recording studio wall effect, absorbing rather than reflecting sound.
    As for removal, a spit coat of shellac is very easily penetrated by a wet, warm cloth. Add a fresh hot cloth every few minutes for maybe 3 changes and the linen should lift off without effort. I haven's yet tried this, so I suppose that's something to add to my experimental proof list, huh? But really, I seriously doubt it's an issue.
  16. Gerard - I never said anything about cotton. That was you. I said canvas.
  17. Sorry again! But hey, when I went to art school (Emily Carr College in 80/81, until I got sick of the lack of decent technical education) we were taught that 'artist's canvas' was usually 100% cotton, with a 'size' of starches added for stiffness which one ought to wash out for non-painting applications. Linen 'canvas' was a lot more expensive, and very rarely used, even by most established painters. The whiteness of a cotton canvas makes less gessoing and other whitening needful, unlike the almost purple-brown of a raw, unbleached linen. Bleaching, regardless of what plant fibre is chosen, takes away from the inherent fibre strength, so in a long-term reinforcement application like rib lamination it would seem a good idea to go with unbleached.
  18. Damon Rondeau

    Damon Rondeau Journeyman Clam Artist Supporting Member

    Nov 19, 2002
    Winnipeg, baby
    Another thought on the asymmetric / ergonomic thing is what some of the guitar builders are up to with wedge designs. Here's an interesting article about what William Cumpiano started doing a while ago.
  19. I thought I would share some of the things Bob Ross did with my bass. First of all I don't know if I would have gone for all this stuff if Bob did'nt live an hour away and would back up his work. Also I like tweaking with stuff and kind of enjoy owning a bass that has so many expirmental posibilities. The removeable C-bouts are the most unusual feature, I know it sounds wierd but when I saw it on his previous bass it just made so much sense. I've had no problems with buzzing or anything, Bob did such a good job fitting them, I know it took him a while. If there were ever to be any problems they would be easy to fix because you can take them out. The neck joint is not a sliding joint but angles up and down, there are two main conecting bolts and two smaller bolts for the adjustments, all the bolts are on the inside. He also modified the end pin with threaded pipe so it is held in with a maple nut. The other thing that is a little different are the tuning machines, he modified some electric bass machines. They look good with the design and are working fine, but we'll see how they hold up. The ribs are lined with linen, not sure what kind but it looks black. Later Marc
  20. Matthew Tucker

    Matthew Tucker Commercial User

    Aug 21, 2002
    Sydney, Australia
    Owner: Bresque Basses, Sydney Basses and Cellos
    My brain hurts ... how about some pix so I don't have to imagine so hard ...