Crawls Backward (When Alarmed)

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Oahu (Valco) Diana Lap Steel Guitar

The projects are piling up (if you could see the Dungeon, you'd see I mean that literally).  This is a quick one before I tackle two more for a (get this) customer.

In the process of discovering off-beat instruments, I've also found myself digging old instrument cases.

And in this instance, we have a cool case and a cool instrument.

This case is still in decent shape structurally, although it could use new hasps for the latches.  I'm in the process of procuring some of them.  With a cleanup, this will be a great case.

And inside it is...holy art deco, Crawfish, what is that?

It's a 1951 Oahu Diana lap steel guitar!


This was made by Valco in Chicago.  Valco made thousands of instruments and amplifiers from the late 1930s through the 1960s.  They were marketed under the brand names Valco, Supro, and National.  They also made instruments for Sears, Montgomery Wards, and others.

Oahu was a music publishing company based in Cleveland, and Valco made Oahu-branded instruments for them.

This particular instrument uses the famous Valco string-through pickup.  It looks like a humbucker, but is actually a large single-coil pickup.  This is the same pickup Ry Cooder put in his famous "Coodercaster" guitar.

The fingerboard is reverse-printed plastic - I suspect it's Lucite.

The "frets" are part of the artwork.  Since this is a steel guitar, it's played with a bar (aka slide).

You wouldn't be fretting this thing, what with the square neck profile and super high action.

This lap steel is in just fabulous shape. There are some chips in the finish and some lacquer checking, but that's part of the charm.  I've been window shopping lap steels for a while, and I finally bit the bullet.

This one only needs a few things before it's ready for battle:  the volume control is wonky, the tone control doesn't seem to do anything except cut in and out, and it needs to be restrung for C6 tuning.  (I'm learning some on that tuning first as a starting point.)

The pickup and controls are one assembly.  Just take out all the screws that hold it to the guitar body.  These are marked with the green arrows.

The two back pickup top plate screws hold the plate down and also go into the body, doubling as mounting screws.  One of these is broken, as you see.

The top plate is magnetically charged from the pickup magnets - it surrounds the strings with a magnetic field, which contributes greatly to the clarity of tone.

The back screws are #8 x 1 1/2 wood screws.  The front screws are #6-32 machine screws.  The front pickup mounting holes are threaded to accept the machine screws.

An interesting mounting arrangement.  I'm not wild about the mismatched screw heads, but I guess Valco figured most people would leave the big chrome cover on the pickup, so they'd never see the screws.

The whole assembly comes up off the guitar.

There is a small yellow lead near the volume control (the furthest pot in this picture).  That's the pickup hot, or output lead.  Be careful not to break it!  The green arrow is pointing to the rest of the broken pickup screw.

The pickup screws provide the ground via the mounting plate and the volume pot.  The only actual ground lead is from the volume pot to the output jack.

If you look at this picture carefully, you'll see why the tone control doesn't work.  A capacitor comes off the volume control as you'd expect and runs to the tone pot.  But there isn't any connection from the tone pot wiper to ground!  I'm not sure if this was just never wired at the factory, or if someone miswired it later.  Either way, I'll get it working.

One way to date old gear is though the potentiometer EIA date codes.

This is the volume pot.  The 6-digit code here is 304930.  The code on the tone pot is 304931.

Using the Triode Electronics EIA code list, we can suss out "304" being Stackpole, the "9" being 1949, and the "30" and "31" as weeks of the year.

So the pots were made in the 30th and 31st weeks (July) of 1949.

The serial number on the guitar is a 1951 number, so the pots were most likely in a distributor or Valco's stock sometime before the guitar was built.  I like playing history detective!

And speaking of history, here's a great page on Valco/Supro/National guitars.  


Post a Comment 5 comments:

  • Thomas Didymus said...
    June 22, 2016 at 2:38 AM
    This is an old blog. I wonder if I can drudge up some support with luck.

    You talk about the serial numbers here, so I'm hoping to find a reference to a list. I've looked and looked. Just got a '55 Oahu, don't even know the model. It's nothing special, but I thought I could find out more with the serial number.

    Thanks for any help.

  • Thomas Didymus said...
    June 22, 2016 at 2:39 AM
  • Yr Fthfl Blggr said...
    June 22, 2016 at 7:09 PM
    Thanks for your comment. It's an older post, but I still see all commments.

    The serial number will only give you the manufacturing date, not the model. Valco made so many models of instruments and I don't think there is a comprehensive list of models and years they were made.

    A list of serial numbers with dates is here though:

    And another great resource, which may help you determine the model, is the Steel Guitar Forum at:
  • Capokid. said...
    June 18, 2017 at 10:18 PM
    Hi. Is this case still available? I'm trying to find a case for an electric tele style mandolin. It's 33" long 11" wide around the bottom and scale length is 20.5". Can you help? Thanks
  • Yr Fthfl Blggr said...
    June 19, 2017 at 10:13 AM
    Hi -

    Case wasn't for sale, it belongs to my lap steel.

    Have you contacted Gator or SKB? They may have something that would work.

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