Crawls Backward (When Alarmed)

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1961 Supro Lap Steel Cleanup and Minor Mods, Pt. 1

I finished painting the exterior of the sunroom.  Whoo hoo.  I still need to fix the rotted corner.  I'll post about that soon.

However, the good news is that I'm back in action in the Dungeon.  Ha!

This is a 1961 Supro lap steel.  You may recall that I acquired it as part of a package with my Supro 1616T amp.  I'm not sure of the model number on the steel - other than the Supro badge and serial number, there are no other identifying marks.

It features the famous Valco/Supro/National string-through pickup.  The electronics are in good shape - I just need to clean it up and restring it and I'll be twanging.
This steel is pretty much as basic as you can get.  Unlike my Oahu Diana (also Valco-made), this Supro has a painted-on fingerboard.   Quite plain compared to the Oahu.

Two thumbscrews hold the plastic pickup and bridge cover on.  Here's the pickup with the cover removed.  Some light corrosion, but it should clean up easily.

I took the knobs off so I can polish the control plate under them.  You can see they're two of the millions of knobs made by Daka-Ware.

Valco and Daka-Ware were both in Chicago, as were many other manufacturers of these kinds of parts.

I want to take of the control plate.  There are two wood screws on the back end - the arrow points to where I removed one.

The two rear screws on the top plate of the pickup hold the pickup down and also hold the control plate down.  Unscrew those and the plate will come off.

You don't need to take the front screws off the pickup unless you want to remove it too.

Here's the control plate.  Notice how simple the whole steel is.  It's just a single piece of wood cut to shape and routed for the controls.

My guess is the bodies were done separately as were the controls.  Then the output wiring was soldered to the output jack, and the plate was mounted to the body.  String it up, and you're done.

You can also see the fading and yellowing of the body next to the control plate.  The paint's a lot brighter underneath. 

The serial number dates the guitar to 1961.  The first 1961 Valco serial number was T51000.

And here's the date code on one of the pots - I think this is the volume.  The "304" is the EIA code for Stackpole (also in Chicago).  The "60" is for 1960, and the "43" indicates it was made in the 43rd week of the year.

The other pot was made in the 49th week of 1960.  So based on these dates, the pots were in Valco's stock probably about the end of 1960, the guitar was probably made and shipped in early 1961.

Here's a great list of EIA codes and how to read them.
I cleaned the pots while I had the control panel off.

I also made one small mod I do to most all of my guitars.  It's known as the "50s Gibson" or "Fezz Parka" mod.  It prevents the guitar's tone from getting darker as you turn the volume down.

It involves moving exactly one wire.

If you look at the rightmost tab on the volume control here, you'll see that the hot lead from the pickup (yellow wire) and the tone capacitor are joined there.  Wiring the tone this way tends to load the volume circuit and cuts treble as the volume goes down.

So what we do is just take the capacitor lead and move it to the center, or output, tab on the volume pot.  Easy as cake.  (Mmmmmm cake).

I really like this mod much better than a "treble bleed" mod.  It's more natural sounding to my ears.  With a treble bleed, it sounds like the treble goes up at lower volume.

It's certainly easy enough to try this mod and see if you like it.

I'm going to leave the original cap in for now.  It's probably leaky, but what the heck.  I don't think it's worth messing with at this point.   The value of this one is .05 uF.  I changed the one in my Oahu to .03, so this is also an opportunity to compare the two values.

 
 
 
 

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