Shop Notes Blog
For many years now I have been finishing my flutes using the same materials and methods, and the results have been favorably commented upon many times by my customers. I tried a few different approaches in the early days of my career before settling on a combo that really seemed to work. Back around 2000, I discovered the many uses of clear-coat marine epoxy and its value as a finish for the inside of flute bores. I’ve been using it ever since. I even use it as a sealer on the outside of my flutes before I add a lacquer finish.
The end results are always excellent. However, there is a “dark” side to this approach.
I chose these finishes because they are not just easy to use and effective, but also because they are theoretically “inert” when cured, and therefore safe for the customer who will be handling them very intimately. I don’t genuinely believe that any chemical finish is ever completely inert, and I would not be shocked to find that someone with chemical sensitivities would not like the epoxy and lacquer, even when cured. So far I haven’t heard from anyone to indicate that this is the case, but I think I can safely assume they are out there, however rare. But the big problem with these finishes is that when they are “active”—meaning being used by the flute maker—they are not remotely safe! They are toxic. Not extremely toxic, but sufficient that continuous low-level exposure can be problematic.
Epoxy does not have a lot of VOCs (volatile organic compounds), but it does have lots of bisphenol-A (BPA), which is an endocrine-disrupter. When I first started using epoxy I thought that the absence of VOCs meant that I didn’t have to worry about fumes. So I used it for quite some time under conditions that were not optimal and so I was heavily exposed to BPA. The lacquer is also not user friendly, being full of all sorts of things you don’t want to inhale or get on your skin.
I eventually wised up and got much more safety conscious, but the overexposure had already happened and I have experienced some long-term health consequences that were either caused by or aggravated by exposure to these chemicals. I’m confident that I can clear these from my system (detox) and unwind some of these problems, but I was advised to simply cease using them altogether.
Normally a change like this might create a bit of a puzzle, namely that of trying to find a suitable substitute. But as it happens, my foray into bamboo flute making led me to an interest in natural finishes, and so I am already equipped with the answer to my dilemma.
I’ll be using something called button shellac, which is an all natural finish (most people are familiar with shellac, made from a resin excreted from lac beetles). You can read more about this if you check out my blog Bamboo Journey. It is food-safe, edible and completely non-toxic. And to top them off I use the Clapham’s Beeswax polish, which is another natural and food-safe product.
The big advantage to the epoxy is that it is totally waterproof. It is used to seal ocean-going wooden boats, so it is very durable and not affected by moisture. When players would ask me what they needed to do to maintain the bore of their flute, I’d say “nothing”. The new button shellac that I’ll be using is extremely tough and also quite water resistant, but now if a player asks me the same question my answer is, “just swab out the bore after you play the flute”. This is what most flute players do as a matter of routine, so it’s not really an appreciable difference.
So future flutes will feature only these natural finishes, which is nice for the end user, but also very important for the flute maker! There is a bit more work involved (though not too much) and there is a bit more time required as well, since the shellac does not cure as quickly as the epoxy does. However, it is a small price to pay for a healthier working environment. I’ve always wanted for my flutes to feature natural finishes, but I succumbed to the allure of convenience and (to be fair) the excellent performance of the epoxy and lacquer finishes. But I have every reason to believe that the new finishes will perform beautifully and make for a genuinely all-natural product.
Published Thursday, August 7, 2025