Rosewood Neck Care

"Tung oil is the best; Never use raw linseed, double boiled can be used but Tung is the best."

Utterly and completely BAD advice.

Raw linseed oil is simply pure linseed oil. It is slow drying and is excellent for rejuvenating rosewood fretboards. All it eventually does is evaporate off and wear off, but much slower than, say, a quick fix treatment like 'lemon oil' which isn't even a proper oil. The only downside to using raw or pure linseed oil is that your guitar neck, and fingers, smell nice (IMO) for a long time afterwards.

Boiled linseed oil on the other hand is rarely boiled nowadays. But boiling linseed oil speeds the drying process, and in so doing creates not an 'oil' but a 'finish' that is hard and glossy. It was boiled once to create a type of lacquer, mostly now it has solvents added to help it dry quickly and do the same thing. In either case it is still called 'boiled'. Put this stuff on your fretboard and you may as well spray a can of poly clear over it. In the UK it was once a regular ritual to use boiled linseed oil on brand new cricket bats, to harden the wood, stop moisture soaking in, and give a gloss finish. I'm, not sure you want that on your rosewood fretboard, especially as once it dries hard it can flake off if damaged or worn.

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That's what Dan Erlewine uses and suggests
in his book. I'm sure some of the "for guitar"
products work well and may be very similar.
Dan recommends it applied once or twice a year
and buffed or burnished after removing any
excess.
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General rule number one about fretboard care is to avoid any products that contain silicone. While silicone oils are inert substances, problems over the long term will be avoided by not using them.

General rule number two is to avoid products that contain waxes. This includes carnauba, paraffin and silicone waxes. You do not want to apply a waxy residue to the fretboard, you merely want to clean it and leave a very thin oil protectant.

What about furniture care products like "Lemon Pledge"? Aerosol furniture polishes contain waxes, petroleum distillates, emulsifiers (detergents), and lots and lots of water. A very light spray on maple to clean it is fine, but aerosol polishes ahould not be used on unvarnished fretbaords. We do not want to apply products containing water to the natural finish of a guitar neck and fretboard.

Pure lemon oil (or other citrus oils) is composed of d-limonene at an amount of 90% or more. There are other minor components that give each of the citrus oils its own unique flavors and fragrances. These ingredients include citral, linalool, geraniol, nerol, citronella, pinenes and other terpenes.

Since d-limonene is the majority of lemon oil (or orange oil), we can look at its properties to determine why it is not suited for fretboard care. First, and most importantly, d-limonene is a very strong solvent. It is used to remove glue, paint, grease, oil and other substances. If an oil with a high percentage of d-limonene were applied to a fretboard, it might even begin to loosen the bindings, fret markers or other trim. Additionally, it could soften some varnishes or lacquers used on necks and bodies. Also the vapors of d-limonene are flammable with a flash point of about 124 degrees F.

What are petroleum distillates? The type of petroleum distillates used in furniture cleaners is a very thin, purified and deodorized mineral oil. Normal paraffin and iso-paraffin oils are generally used since they are less agressive to finishes and have lower odors. They are also flammable but the flash points are usually above 200 degrees F.

To clean a natural finish fretboard or neck, little is required in the way of chemical treatment. Basically you use a clean rag to remove as much of the dirt build-up as possible. Around the frets, grime often gets packed in and is very hard to remove. A plastic scrubbing pad is recommended since it will be softer and less likely to scratch, although very fine grades of steel wool (000 grade) may be used with care. Either type of scrubber should be plain; NO SOAP as is often in SOS pads or similar. Watch the steel wool because any fine bits of metal that are shed by the pad will be attracted by the magnets of guitar pickups.

A furniture oil may be placed on a clean rag and wiped around the hard to clean spots to assist the pad in removing the dirt. Once the fretboard is clean, wipe the entire surface with the oil dampened cloth to seal it. The furniture oil that is left behind will replenish the oil lost from the surface of the wood and help retard further losses. Use as little as possible; you just want to put a slight gloss on the surface.

Select a furniture oil that contains petroleum distillates. It is required by Federal law to have a child resistant cap and to state on the label: "Contains petroleum distillates. Harmful or fatal if swallowed". Lemon oil makes the product smell better and might add a little cleaning action due to its solvency, but is not required. Avoid silicones and waxes.

Buy a good quality furniture oil. Since you use it sparingly and only clean once or twice per year, a typical bottle will last a lifetime.
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