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 with the exception of serial numbers 77400, 76478 and 77410, which had maple back and rims. 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

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)

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!