I just got an old corner cupboard. It was in a house that had water in the crawlspace, so the cupboard has a little dry looking grayish mold on it, even on the glass in the door. I thought rather than just wiping it off with a damp rag, I should put bleach in the water, but I don't know how weak I can make it and it still kill the mold. The cupboard is from the early to mid 1800's but the finish is not original. It was refinished with minwax stain about 35 years ago. The previous owner has occasionally dusted it off with a barely damp rag without hurting the finish. I thought I'd vacuum it to get the loose dust and spiderwebs off, and leave both doors open for a good while to make sure it dries out, in case there's dampness in the wood. My house is dry and has central heat. Then I thought i would clean the mold off with bleach/water without soaking the wood, just wipe it off with a barely damp cloth, and leave the doors open for a good while longer to make sure it gets dry inside. I tried googling but found conflicting info on the bleach to water ratio. And if anybody has a better suggestion for cleaning, I'd like to know.