Crawls Backward (When Alarmed)

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Oahu Diana (Valco) Lap Steel Restoration

The volume control is a little crackly, so I'm going to hit it with some MG Chemicals Control Cleaner.  This is pretty much the best cleaner for pots that I've found.  A lot of folks use Deoxit, but that is really not for pots - it's for contacts.

You might notice the price tag - I got this at Baynesville Electronics.

The cleaning got the pot going well.  I don't like replacing old pots it I can avoid it.

I also removed the broken pickup mounting screw.  Piece of cake to use a vise-grip on it.  It came right out.

Speaking of replacing pots.  A couple of things with the tone control.  First, it was not wired correctly at all.  The tone cap should connect to one outside lug of the pot, which is where it was connected.  However, the middle (wiper) lug wasn't connected to anything!  So it wouldn't do anything.

I rewired it with the middle lug going to ground.  What it does now is filter off highs to ground.  I also wired it so that turning it counterclockwise rolls of the highs.  The original factory wiring was the reverse - which is not the way they're usually wired.  So I just used the modern convention.

The old pot itself was shot.  I got all kinds of crazy readings on it - mainly open!  So I put a new 250K CTS pot in there.

I also wanted to change the tone cap value - I opted for an .033 uF instead of the original .05 uF.  I find .05 to be a little too fast (i.e., rolls off treble too quickly) and dark for my taste.  I did use a Russian K40-9Y PIO cap since I have a bunch of them on hand.

Someone put what I believe to be an aftermarket nut on it.  It's stamped "A P&M Co."  From what I can determine, these folks made bars (slides) and other accessories.  The nut popped off when I took the strings off, so I used epoxy to fasten it back on.

Here you see the caul/clamp I used to hold the nut in place while the epoxy set.

I see a wood shim and I want to paint it black.

Someone put a wood shim under the front of the nut to prevent it from tilting forward under string pressure.  (This is why I suspect it was an addition).

I reused the shim, but I decided to paint it black to better blend with the fingerboard color.

With all of the other work done, I polished up the chrome on the big mounting plate for the pickup and bridge.  It's in great shape, and polishing it really made it look terrific.

I also used a fine grade rubbing compound to polish the whole guitar, and I also polished the plastic fingerboard.

The guitar has definitely seen some use, but it's been well taken care of.

You may recall my research on the Hickok factory in Cleveland.  I decided to see if I could get a picture of the former Valco factory in Chicago where this lap steel was made.

The street address was 4700 West Walton St., Chicago 51 (now 60651).  Here's the building as it appears today, thanks to Google Earth.  Unlike Hickok, there is nothing visible on the pictures related to Valco.  Of course, Valco was out of business in 1968, so everything is probably long gone.

As with the Hickok factory, this is a smaller building than I would have thought.  Apparently this was the manufacturing plant; the sales offices were not at this location. 


Post a Comment 9 comments:

  • Toy Making Dad said...
    June 8, 2012 at 1:37 PM
    "I see a wood shim and I want to paint it black..." - Crawfish.

    Hey - You really should include clips of these instruments being played after you restore them. Maybe even before and after... just saying.
  • Anonymous said...
    May 3, 2014 at 4:39 PM
    Greetings, im having a horrible time replacing the pots in my Oahu Tonemasternumber 1 I've never done anything like this before and I'm very nervous about it I don't know where any of the wires go so I pretty much need a rewire for dummies I have to 250 K pots and a brand new CTS jack I just need to know where everything goes if I can I'm going to send you pictures of what I have if you could use plain English and help me get my steel back together I just wanna play it that's all thank you
  • Yr Fthfl Blggr said...
    May 6, 2014 at 7:38 PM
    Sure, send me a picture. Be sure to give me a return email address. The wiring on these steels is very simple.
  • August 9, 2014 at 9:52 AM
    Hey man! Awesome finding your blog here. I'm also doing a diana, and I just received the pickup back from re-coiling by Tom brantley in NY. I'll follow your wiring from the picture above, but I'm a little confused, is there no ground going from the pickup? (I'm a newbie)

    - Fredrik, Denmark.
  • Yr Fthfl Blggr said...
    August 9, 2014 at 9:34 PM
    Hi Fredrik -

    Yes, there's only one lead from the pickup - the hot lead. The ground is the pickup housing itself. When it's mounted in the plate, it's grounded.

    I wrote about this in the post before the one you read:

    Those pickups are fantastic.

    Thanks for reading!
  • August 10, 2014 at 6:57 AM
    Absolutely awesome pickups, it is the reason I bought it in the first place, only the pickup got busted during the shipping, so it had to be rewired. I do love the design of the oahu though! However, I have been led to believe it is a humbucker, but you say it's a single coil?
  • August 10, 2014 at 2:53 PM
    Hmm... The output is really low, seems like a fault. Do you know what it can be? I mean, I had to crank my blues junior to 12 o'clock before getting a decent volume. On any other guitar that would blow my ears.
  • Yr Fthfl Blggr said...
    August 18, 2014 at 7:34 PM
    Can you measure the DC resistance of the pickup? Maybe there is an issue with a coil. They have a fair amount of output - you shouldn't have to turn an amp up that much to get good volume.
  • Yr Fthfl Blggr said...
    August 19, 2014 at 9:05 AM
    One other thought. Try wiring the pickup direct to the output jack and see how that works. If the output is higher, that means you have a wiring fault elsewhere.

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