Flattop acoustics conversion?

Lap steels, resonators, multi-neck consoles and acoustic steel guitars

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Rick Rienks
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Joined: 5 Jul 2024 6:31 am
Location: Oregon, USA

Flattop acoustics conversion?

Post by Rick Rienks »

As I aged I developed problems with my hands and decided I might get back into playing if I switched to slide. Finding a great deal on a ‘61 Supro cinched the deal. I began working my way to functionality.
Recently I met a 91 year old fellow who voiced a familiar complaint - his hands. I suggested we try to convert his acoustic from fretted to slide.

Once that was completed I tuned it to standard guitar tuning saying we might need some assistance in selecting a tuning and string gauges.

Thus I turn to you all for ideas and suggestions moving forward. The string height seems workable. I wonder about open E tuning as regards gauges/string pull. Thanks for any information you may offer.
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Stanislav Paskalev
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Re: Flattop acoustics conversion?

Post by Stanislav Paskalev »

The typical tuning for converted guitars would be open G low-bass - DGDGBD. There are couple of textbooks, both new and old ones that deal with playing lap in open G or open A - which a tone higher at EAEAC#E. Both of these tunings work with the gauges in a standard guitar string set.

With those conversions it is important to also pay some attention to the bridge. On most acoustic guitars the bridge is slanted and notched on some strings to account for intonation changes when a string is fretted. When playing steel you want a straight bridge that is square with the nut. Otherwise with a straight bar that is parallel with the frets the bass strings may be a little flat.

If you're interested in pulls I'd say switch to a C6 string set for a C6 or similar tuning. Those often contain 4 plain strings and it is easier to bend those. Bending wound strings does not work as good.
My current preferred tunings: Bb-C-Db-E-G-A-B-D on 8 strings and C-E-G-A-B-D on 6 strings
D Schubert
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Re: Flattop acoustics conversion?

Post by D Schubert »

A Grover extension nut is the simplest way to convert acoustic guitar for lap style, they've been making them for years. For slide tunings you should be able to use open D or open E or lo-bass G with medium gage strings that are probably on the guitar already.

https://www.stewmac.com/luthier-tools-a ... gImyPD_BwE
GFI Expo S-10PE, Sho-Bud 6139, Fender 2x8 Stringmaster, Supro consoles, Dobro. And more.
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Brooks Montgomery
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Re: Flattop acoustics conversion?

Post by Brooks Montgomery »

also try (low to high) FACFAC it’s a tuning that both Rob Ickes and Jerry Douglas use on occasion.
A banjo, like a pet monkey, seems like a good idea at first.
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Lee Rider
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Re: Flattop acoustics conversion?

Post by Lee Rider »

I use a G11 tuning: GBDFAC (low to high).

I had a great dreadnought acoustic guitar, a '62 Epiphone Troubadour. It was an odd guitar, 12 fret to the body, 2" neck width at the nut, straight bridge and flat fingerboard. Gibson had recently obtained Epiphone and used what looked like the same body they used on the Dove flattop. They just moved the bridge south to compensate for 12 frets at the body, so the bridgplate was about and inch and a half or so from where the bridge pins came through the top! It was lightly braced so that you could use nylon strings on it. I flatpicked that guitar with bluegrass pickers for a while until I got a Martin D-35S (I have large hands) then put a Kluson high nut on it and played it lap style. I think Kelly Joe Phelps played the Gibson version of that guitar. Should have kept it...
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Stanislav Paskalev
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Re: Flattop acoustics conversion?

Post by Stanislav Paskalev »

If one wants to try the waters with C6 on regular guitar gauges the following compromise tuning will do EADGbe (standard) => EAC#Gce (D down to C#, b up to c)

It is not exactly a strum tuning but contains dim, minor, major, dom7 and min6. Inversions and maj7 are available with slants and splits.

Code: Select all

All notes
    /----+----+----+----+----+----+----+----+----+----+----+----+----+----+----\
    | 1  | 2  | 3* | 4  | 5* | 6  | 7* | 8  | 9  | 10 | 11 |*12*| 13 | 14 | 15 |
    |----+----+----+----+----+----+----+----+----+----+----+----+----+----+----|
 E  | F  | F# | G  | G# | A  | A# | B  | C  | C# | D  | D# | E  | F  | F# | G  |
 C  | C# | D  | D# | E  | F  | F# | G  | G# | A  | A# | B  | C  | C# | D  | D# |
 G  | G# | A  | A# | B  | C  | C# | D  | D# | E  | F  | F# | G  | G# | A  | A# |
 C# | D  | D# | E  | F  | F# | G  | G# | A  | A# | B  | C  | C# | D  | D# | E  |
 A  | A# | B  | C  | C# | D  | D# | E  | F  | F# | G  | G# | A  | A# | B  | C  |
 E  | F  | F# | G  | G# | A  | A# | B  | C  | C# | D  | D# | E  | F  | F# | G  |
    \----+----+----+----+----+----+----+----+----+----+----+----+----+----+----/

 Chromatic scale
    /----+----+----+----+----+----+----+----+----+----+----+----+----+----+----\
    | 1  | 2  | 3* | 4  | 5* | 6  | 7* | 8  | 9  | 10 | 11 |*12*| 13 | 14 | 15 |
    |----+----+----+----+----+----+----+----+----+----+----+----+----+----+----|
 1  | b2 | 2  | b3 | 3  | 4  | b5 | 5  | b6 | 6  | b7 | 7  | 1  | b2 | 2  | b3 |
 b6 | 6  | b7 | 7  | 1  | b2 | 2  | b3 | 3  | 4  | b5 | 5  | b6 | 6  | b7 | 7  |
 b3 | 3  | 4  | b5 | 5  | b6 | 6  | b7 | 7  | 1  | b2 | 2  | b3 | 3  | 4  | b5 |
 6  | b7 | 7  | 1  | b2 | 2  | b3 | 3  | 4  | b5 | 5  | b6 | 6  | b7 | 7  | 1  |
 4  | b5 | 5  | b6 | 6  | b7 | 7  | 1  | b2 | 2  | b3 | 3  | 4  | b5 | 5  | b6 |
 1  | b2 | 2  | b3 | 3  | 4  | b5 | 5  | b6 | 6  | b7 | 7  | 1  | b2 | 2  | b3 |
    \----+----+----+----+----+----+----+----+----+----+----+----+----+----+----/
My current preferred tunings: Bb-C-Db-E-G-A-B-D on 8 strings and C-E-G-A-B-D on 6 strings
Tom Campbell
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Re: Flattop acoustics conversion?

Post by Tom Campbell »

I have a tapered neck flattop. I noticed the "Grover" nut 1st string and 6th string slot over-hang the neck slightly...is this a problem?
I tend not to think so being the frets are now only used as a "note marker"...I could be wrong.
D Schubert
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Re: Flattop acoustics conversion?

Post by D Schubert »

Question: I have a tapered neck flattop. I noticed the "Grover" nut 1st string and 6th string slot over-hang the neck slightly...is this a problem?

Opinion: I'd say it was a feature, not a flow -- as it slightly increases the string spacing at the nut end, making it a tiny bit more like a square neck guitar.
GFI Expo S-10PE, Sho-Bud 6139, Fender 2x8 Stringmaster, Supro consoles, Dobro. And more.