For a low-end guitar is there a product that can be used inside the sound box to keep the wood conditioned without risking damage to wood or glue. The recently found instrument is 30+ years old; its in good shape, but I would like to protect it despite likely sound alteration with a product. I was thinking Murphy's Soap or a light oil. Thoughts on risk/benefit to wood or glue.Thanks, Jeff.
If you mean inside the body of an acoustic guitar, you should put nothing in there and leave the wood open. If it's a low-end guitar, it's likely nothing you do will make much of a difference, since laminated woods usually do not age the same way and can't be reconditioned like solid woods can be. Steps you can take to care for the inside of an acoustic guitar:
- Use a vacuum with blower feature or compressed air to blow out dust and debris. Ideally, take all the strings off and blow out the inside and remove anything that shouldn't be in there. Don't use any cleaning cloth or cleaning product.
- Evaluate the humidity level of the guitar (see below) and if it is dry, use a humidification product (which are often placed inside the body). If it is wet, put it in a dry environment and/or use a dehumidification product (which also may go inside). Note that there are affordable products (Planet Waves makes one, at least) that will regulate the humidity automatically whether it is dry or wet.
Aside from that, I wouldn't do much at all to the inside of a guitar. You could inspect it with a mirror for damage. You could make sure any labels inside the guitar are not about to fall off.