The Luthier's CSI: November 2021 American Standard "Rib Cancer" resurrection

Discussion in 'Luthier's Corner [DB]' started by james condino, Oct 24, 2021.


  1. james condino

    james condino Spruce dork Supporting Member Commercial User

    Sep 30, 2007
    asheville, nc
    A few years ago I took in a couple American Standard project basses in rough shape in trade for a new neck and scroll graft on another old American Standard. Seems like a great deal, no??? A good condition and setup American Standard is one of my favorite working man's mid 20th century US basses- strong, confident, a great low end, and tough.

    Kay and similar basses were made from a decent looking outside layer and the rest is whatever was on sale at the veneer factory. American Standards were butt ugly, but the tops were made from rotary cut sitka spruce and blow the doors off the rest in their class; very close to a hybrid bass. They also had the first patent circa 1934 for the use of resorcinol, a two part urea formaldehyde based glue that was used in a vacuum press construction- very high tech for almost a century ago.

    Well....I learned a ton from these old basses. About 50% of American Standards suffer from the dreaded "rib cancer". Today we know that resorcinol glue is temperature sensitive: below 70 degrees F it does not bond properly. It is my belief that the rib cancer issue stems from unheated shop production in Cleveland during the cold months of the year. The H.N. White company made them and they were primarily metal working guys; no heat or glue issues in a metal shop. Great horn guys still learning to be great wood guys:

    AS rib cancer 101.jpg
     
    Last edited: Oct 25, 2021
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  2. james condino

    james condino Spruce dork Supporting Member Commercial User

    Sep 30, 2007
    asheville, nc
    I tried all the tricks I know over about 15 months and nothing would bring back this one particular bass to a level where I was confident that it would hold and I could pass it on to another owner. Here it is on the rotating torture rack with more rib cancer visible (another old AS is upright on the left):
    DSCN1976.5.JPG

    Am std bass superstation.JPG

    Every time I'd get about 85% there, another backslide would happen....

    Along the way I acquired another back & top, sans everything else; 'another rib cancer patient.

    DSCN6503.JPG
     
    Last edited: Oct 24, 2021
  3. james condino

    james condino Spruce dork Supporting Member Commercial User

    Sep 30, 2007
    asheville, nc
    I swapped parts among several basses. At one point I got a call from another well known builder and sold off the cleanest of the tops. Frustrated, I put them up for sale all over the web. At one point I had a top and back set advertised for $250 and the only response was from a guy in Germany who was mad as %$#@ that I wouldn't ship them to Europe for free. They almost went into one of the regular shop bonfires...

    During this time, my new bass building skills were getting more refined and also more adventurous along with more complicated repairs. I had a circa 1880 Hakes bass in for a top off repair that was a basket case- the original ribs had been repaired and overlayed so many times that the total thickness was almost 6mm thick! Alongside it was a different American Standard that had mild rib cancer. I was able to 100% repair the AS bass with just a few ounces of hot hide glue. While the Hawkes was working great when it left, I felt that it really needed a complete new rib garland to fully express itself. The original was a huge choke on everything; DEFINITELY NOT living up to its $35,000 price tag...

    I had also attended a couple of Jim Hamm's double rib building workshops and was eager to give it a try.....
     
    Last edited: Oct 24, 2021
  4. james condino

    james condino Spruce dork Supporting Member Commercial User

    Sep 30, 2007
    asheville, nc
    Traditional bass rib bending is done over a heated pipe. A gas, electric, or candle source is used to heat up a pipe in a vise, thin the rib wood, rub back and forth trying to both bend the wood and not burn the &^%$ out of it.

    DSCN2034.JPG

    To make a laminated rib, it gets much more complicated. You need a good vacuum system, a set of moulds, and a solid plan to execute it all. It took me about six months to settle on a nice vacuum system for my needs and then build it. After I built it, it took a about a 1/2 pickup truck of sawdust making up a series of very accurate moulds.

    Next, I needed to test the whole system. With a lot of education and background in engineering, that was a big project. I eventually made 35 different test pieces. Maple, mahogany, spruce, Brazilian rosewood, ziricote, 5 different types of glue, 3 different types of carbon fiber, kevlar, and aramid cores....then I stress tested them all to failure. The results were quite unexpected, varied, and a couple of them downright shocking. Beyond all of the strength issues, I also measured the tone- the most surprising one measured a 5th higher in pitch. I'll be publishing an article with all the nerdy results early next year for the three people interested...
     
    Last edited: Oct 25, 2021
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  5. james condino

    james condino Spruce dork Supporting Member Commercial User

    Sep 30, 2007
    asheville, nc
    I've got three new bass builds on the books for the coming year. One is for a quartet I'm building from all North Carolina tonewoods, thanks to a generous North Carolina Arts Council Folklife grant. The two others will be in my modern style from the last of Lorax trees that I've acquired from several old geezers that had horded them for a century.....

    The complete new rib garland for the old American Standard top & back plates was the perfect proof of concept before I dive into the new Condino basses. It also meant that when finished, as far as I know I am the only place in the world that can fabricate brand new American Standard parts- upper bouts, lower bouts, C bouts, and top + backs to original factory spec or any configuration you could ask for.

    One of the pleasant surprise of my test pieces was how much I liked the voice of padauk. While it starts out a bright red, after a few months of UV light exposure, it darkens- to almost the identical color dark red that matched the old American Standard top. Great color match with minimal finish work! For this configuration, I chose local red spruce for the core. Anyone else would pay a huge price for that much material, but mine comes from about 20 miles away and I have an infinite source so I have a LOT of it. Tech nerds: I chose three layers, 1.2 mm inside and outside with a 1.1 mm cross grained core of red spruce. The original American Standard ribs I measured were approx. 3.4 mm, all maple, with the inside layer cross grained. On a solid wood carved bass I shoot for approx. 2.7mm total thickness. The choice on this was first tonal, second structural, and 3rd color. All of those specs are nonstandard, so I spent about a day resawing, milling, and thickness sanding them to my specs here in the shop.

    I pre bent all of the parts. Remember scale: that mould is approx. 1/2 sheet of mdf! Lower bout #1 before glue up:

    DSCN2060.JPG

    All sucked down in the vacuum press, approx. 20 pounds per square inch uniformly over the entire surface:

    DSCN2074.JPG

    I let that cure out for approx. 24 hours in the press while under a heat blanket to ensure proper curing.
     
    Last edited: Oct 25, 2021
  6. james condino

    james condino Spruce dork Supporting Member Commercial User

    Sep 30, 2007
    asheville, nc
    With a traditional build, the ribs need to go on a massive frame that is about three full sheets of plywood or more. With the laminated ribs, they stay so perfectly stable that I no longer need any big forms during assembly. Here are the C bouts getting the blocks glued on:

    DSCN2427.JPG

    Upper bouts and neck block being leveled out on the sanding deck:

    DSCN8400.JPG
     
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  7. james condino

    james condino Spruce dork Supporting Member Commercial User

    Sep 30, 2007
    asheville, nc
    A standard feature on my basses these days is a magnetic trapdoor / access panel in the C bout. They have been slowly evolving since I did the first one about ten years ago. My early ones used screws; thanks to Mathew Tucker for the idea of using neodymium magnets. I've made about a dozen since. I use them for hidden neck hardware with the removable necks, repairs, internal microphones / pickups, and always adjusting the soundpost for the gig room as well as the occasional stage gag pulling out a rubber chicken or tequilla bottle. Here are a couple of retrofit ones:
    DSCN5937.JPG


    1938 Kay trapdoor removable neck conversion 1.JPG

    1938 Kay trapdoor removable neck conversion 2.JPG

    Here is the new one initial cut- incredibly nerve racking until it is done!

    DSCN8386.JPG

    The finished inside, with the magnets now hidden in between the wood layers:

    DSCN8395.JPG

    Most of the 20th century US ply basses used a kerfed lining, so I try to keep with the tradition for those. These are quite wide with the kerf only 2/3 deep, so the end result is an I beam structure. On my new builds they tend to be solid.
     
    Last edited: Oct 25, 2021
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  8. james condino

    james condino Spruce dork Supporting Member Commercial User

    Sep 30, 2007
    asheville, nc
    The parts moved to my giant adjustable bowling ball vise workbench and coming along nicely. I've started the outside lining in padauk; that combined with an large inside lining makes for a nice subframe for the whole rib garland and also provides a nice outside bumper.

    DSCN8393.JPG

    I'll post more later in the week....
     
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  9. Joshua

    Joshua WJWJr Staff Member Gold Supporting Member

    Aug 23, 2000
    Connecticut
    I'd add a like to every post, but it's just easier to type "amazing work!" and get it done in one shot.

    :D
     
  10. The padauk looks great!
     
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  11. Steven Ayres

    Steven Ayres Supporting Member

    Mar 11, 2007
    Northern Arizona
    James, is this syndrome a problem with the Kings as well, or just the AS?
     
  12. GretschWretch

    GretschWretch Supporting Member

    Dec 27, 2013
    East Central Alabama
    Is it just my imagination, or is that bass on the left in the photo a fractional-sized instrument?
     
  13. I’ve only played one AS, a ‘37 with humped shoulders that I don’t recall having cancer.

    Over the years I’ve owned two Kings, my ex-‘39 and my current ‘35. Neither had it.

    The ‘35 is so clean and shiny you’d think it was a new bass from six feet away.
     
  14. misterbadger

    misterbadger Supporting Member

    Sep 13, 2012
    Northern California
    Fantastic work, as always!
     
  15. Ed Fuqua

    Ed Fuqua

    Dec 13, 1999
    Columbia SC
    Chuck Sher publishes my book, WALKING BASSICS:The Fundamentals of Jazz Bass Playing.
    great work James!
     
  16. eh_train

    eh_train Supporting Member Commercial User

    Jan 12, 2004
    Toronto
    Owner, Stand Up Guy Basses (Repair/Sell/Buy upright basses)
    James, fantastic work as always!

    Re your statement above, you are, absolutely, the go-to guy. BUT, the pic below is of my fabrication of a replacement American Standard upper treble bout. Maple / mahogany / maple veneers with a layer of Kevlar tissue.

    IMG_0349.jpg
    IMG_0349.jpg
     
  17. james condino

    james condino Spruce dork Supporting Member Commercial User

    Sep 30, 2007
    asheville, nc
    Nice work Paul! You know better than anyone else here how much work goes into that small section....

    I've only seen the rib cancer issue with the American Standards. My guess is that they were built in a different section of the buiding with less heat.

    The entire American Standard vs King Moretone is a mystery to me. They were built in the same factory but the differences are huge- American Standards are buttugly with mediocre materials and zero style. Kings are beautiful and graceful and curvy and used exceptional materials- even on the insides, and they are dripping with style from all angles...
     
  18. Jazzdogg

    Jazzdogg Less barking, more wagging!

    Jul 29, 2006
    San Diego, CA
    Wonderful post, Mr. C. Thanks for sharing with us! :)
     
  19. Levin S

    Levin S Supporting Member

    Apr 21, 2007
    Charlotte N.C.
    Best in the business!
     
  20. james condino

    james condino Spruce dork Supporting Member Commercial User

    Sep 30, 2007
    asheville, nc
    One of the reasons why I think old American Standards sound better than the other 20th century US ply basses is the construction: the three primary layers of the top were rotary cut sitka spruce making up approximately 75% of the top. The two smaller cross grained layers are tulip poplar, but much thinner. Lombardy poplar has a long history in instrument making, so it would make sense that they would combine the spruce with a local poplar. Essentially you have a solid spruce top with a bit of structural reinforcement; an engineered hybrid. All of the other basses of that period were primarily pretty wood on the outside and then whatever was on sale for the inside.

    A closeup with the new padauk ribs & outside linings:

    DSCN8493.JPG
     
    Last edited: Nov 2, 2021
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    Primary TB Assistant

    Here are some related products that TB members are talking about. Clicking on a product will take you to TB’s partner, Primary, where you can find links to TB discussions about these products.

     
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