Watch out with that Central Heating in Instrument Construction & Repair Posted July 7 · Edited July 7 by Fdracula110 Understood. I'm not talking about a wet rag. The nature of hide glue, in both the violin and the vintage concertina, is subject to problems in either direction. That is, hide glue does not react well to either too much or too little humidity. But if you keep the glue in, "it's" comfort zone, the wood will do generally well. I don't think I would use that method in London but in the southwestern US it can be helpful. PS violins do have steel, silver, gold and platinum strings.