I used it on my shed. Comes in a range of colours and finishes. I used a satin. Waterproof and is absorbed into the wood, pine in my case, and needed two coats. Not tried on balsa but I suspect it would soak in with the first coat and produce the final finish with the second coat. Not cheap so unless you have some already a bit costly to try. It's very resilient and shows no sign of fading after two years on my shed. I will try some on a piece of balsa when time permits and post the result.