Materials

Timber

Gibson used its highest quality woods for the construction of the L-5; holly for the headstock overlay, spruce for the top and internal top braces, ebony for the fingerboard and maple for the neck (the company described the neck as having a ‘three-piece’ construction – two sections of maple separated by a centre lamination of a dark coloured wood that may have been mahogany).

All known Loar-signed L-5s had maple rims and a birch back (as did all other Gibson guitars of the period) with the exception of serial numbers 76478, 77400 and 77410, which had maple back and rims (Serial number 76478 is likely to be the first Gibson guitar of any description to be fitted with a maple back and maple sides). L-5s built after Lloyd Loar’s departure from Gibson in December 1924 have figured maple back and rims.

Left: Birch backed Loar-signed L-5 Serial No. 76480 shipped 1924

Right: Maple backed L-5 Serial No. 91774 shipped 1935

Gibson’s catalogue O (issued in either late 1924 or early 1925) stated: “Sounding boards are carved from Adirondack, West Virginia, Norway or Pacific Coast spruce of the very highest grade and quality available.” The catalogue continued: “Back-boards are fashioned from the finest quality straight and curly grained Northern Michigan maple or birch, depending on the style and grade of instrument.”

There’s no model-specific indication of wood but the above statement implies – rather misleadingly – that the Master Models were “curly grained Northern Michigan maple,” when in fact, most L-5s had maple sides and a birch back.  

Gibson used the services of the following wholesale suppliers; Julius Breckwoldt and Son of Dolgeville, New York; Edward Hines Lumber Company of Chicago and the Posey Manufacturing Company in Washington State. Hardwood was air dried for five years before being used in production.

A 1923 Gibson production book indicates that Oregon spruce (better known today as Sitka spruce) was used for the soundboards of most models while West Virginia spruce (better known today as ‘red spruce’ or Adirondack spruce) was reserved for use on the company’s most expensive guitars and mandolins.

The production book also specifies how many grains per inch and the degree of end grain deflection from vertical that was acceptable for each model. 

For more on the timber that Gibson used during the Pre-War era click HERE

Pearl

Prior to World War II, Gibson did not cut or inlay its own mother of pearl. Between 1903 and 1930, Aumann Brothers Pearl of Detroit, MI was Gibson’s main source of pearl inlays, while Union Pearl Works of Brooklyn, NY appears to have become Gibson’s major pearl vendor through the first half of the 1930s.

Metal parts/Plating

Metal parts – the tuners, the tailpiece, the pickguard-support and the screws – were initially silver-plated. L-5s built after Lloyd Loar’s departure from the company in December 1924 have gold-plated hardware. Apart from a brief period from 1929 to 1931, Gibson subcontracted out its electroplating needs.

Plastic parts

Gibson used nitrocellulose-based plastic for its bindings, pickguards and – in the case of some block neck L-5s – its fingerboard inlays.

Pearloid fingerboard inlays (Serial Number 87568)

Unfortunately, this material tends to deteriorate with age and the corrosive outgas emitted as the material breaks down can damage the guitar’s finish and metal parts. Confusingly, the plastic binding and pickguards found on some pre-war guitars remain unaffected while relatively new instruments can exhibit signs of decay!

Pickguard rot on a 1930s Gibson L-10. Note the extensive corrosion to the frets and pickguard bracket.
 
Picture courtesy of Joe Vinikow (archtop.com)

This rot, below, is on L-5 Serial Number 92500

Images courtesy of Nathan Fasold, Black Book Guitars

For more on Gibson’s pre-WWII suppliers and practises see Spann’s Guide To Gibson 1902 – 1941 published by Centerstream ISBN 978-1-57424-267-6. Highly recommended!