At 9:39 pm -0700 30/3/07, Jim Johnson wrote: > I have a customer with a Kawai grand which has apparently been used as a >litter box. I'm looking for suggestions for removing stains from the >soundboard without further damaging the strings with cleaning liquids. As others have said, you will need to replace the bass strings at least. While you have the strings off, first slowly remove the superficial dirt with cotton rags damped with just plain water. It is pointless using arbitrary cleaning products, and any detergent is likely to drive the staining deeper into the wood, since the urine has almost certainly passed through the lacquer. The most likely product to remove the stain is oxalic acid. Buy the crystals and not some product that simply contains the acid. You'll find a supplier here <http://froogle.google.com/froogle?q=oxalic+crystals>. Make a saturated solution by mixing some crystals into hot water but use the solution cold in the first place to test the result. Work on a test patch and be very patient -- the action of the acid is subtle and effective but not immediate. Wet your patch with the solution, leave it to work, then wipe off and apply more and so on. The hotter the solution the faster the action, but don't overdo it, and again _be_patient_! Provided it works it will work well and there is no danger of bleaching the wood of its natural color. It's best to wear latex gloves when working with oxalic acid, since it will make your hands itch or worse otherwise. Regard it as a deadly poison (which it is in sufficient quantities) and don't let the cat drink it. JD
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