Readers of this blog frequently email with questions about the cleaning and restoration of helmets. I don't really think that anything can be restored, entropy being what it is, however nearly anything can be conserved.
"Restoration" makes me think of Norma Desmond:
This post shares some things I learned from twenty years in museum work.
(Me with Custer's shoulder strap
and Lee's sash, both in the
holdings of the Public Museum
of Grand Rapids Michigan)
The old curator sez:
Conservation means stopping the agents of deterioration from further degrading the object, and, protecting the object from future degradation.
Active rust, grime, and mold are three things that can degrade or damage a helmet. Those conditions need to be halted to prevent further deterioration of that helmet.
The greatest tools in conservation are:
1. a rough towel
2. a little warm water
3. an eraser
4. a soft toothbrush
5. a dehumidifier
6. a very light touch.
I qualify this whole discussion with the knowledge that one can do anything that one wishes with an object that one owns - cover it with sequins if that's what tickles the fancy; hey, its your helmet, not mine. But if one wishes to take a more measured approach here are some things to consider.
Set aside a cast-off towel to be used for cleaning your helmets. A rough toweling will remove 60% of the crud that's eating your helmet. The soft tooth brush will remove most rust scale, and for removing very surface rust a pencil eraser can be very effective.
Warm water, with a drop or two of dish detergent used in combination with that towel (moist only) will work wonders in removing grime, here's where patience and a light persistent touch will remove detrimental material but not compromise the object or its finish.
Mildew and active mold blooms are very frustrating as once they establish a beach head in leather it is usually there for the duration. The impulse is usually to hit it hard with bleach or some equally noxious fluid to kill the mold and the spores, but all that will do is damage the leather and lead to its quick demise. Leather "treatments" merely lock in the spores which can remain dormant for many years only to erupt later. The best thing with mold is to towel or brush the visible mold from the surface and plug in the dehumidifier - forever. Once the environment dries out the mold will stop growing; if the environment getshumid again the mold will reappear, much to the regret of the collector. My dehumidifier runs every day and my helmets are much healthier for it.
Meet Meis van der Rohe
"less is more" philosophy; maybe that's why "conservative" and "conservation" have the same root. The idea is simply to retard or stop the further degradation of the object.
This brings us to the last step, especially in the prevention of further rust. Micro crystalline wax is a staple among museum conservators, it provides a protective (and reversible) coating on metal to keep it from rusting further. The pits caused by rust cannot be filled in, but the offending oxidation can be removed and the wax can be applied to prevent rust from becoming active again.
Gaylord Inc. carries a full range of museum and library conservation supplies and they are an industry standard in the museum world.
I love "before" and "after" shots, so kindly indulge me.
This is one of the rusty and crusty liner fasteners on the helmet as purchased