Before making my first PVC bows, I did research and also wondered, as I’d hope most folks would, how they break when and if they do. The general consensus seems that if the PVC isn’t overheated or scorched during the heat-gun application, a PVC will tend to buckle rather than break. After all, they’re quite flexible and can make functional bows.
As mentioned, when I make thumb rings, I keep a schedule 80, 3/4″ PVC shortbow handy for testing the quality of a ring at various stages of draw. I usually fire a few rounds into the grass as well, to test accuracy. Perhaps worth noting, I leave this bow strung, with a 16 strand flemish twist.
Today, while modifying a ring that was a bit awkward with heavier draw weights, I grabbed the PVC bow and began pulling back and slowly returning the string to brace height. I repeated this, pulling hard. With no perceivable warning, the bow snapped. It did not buckle. It snapped, quickly, with an audible crack.
The break occurred underneath the leather wrapping, which is an old belt cut into thin strips and lightly glued. Whether this breakage was due to the leather restricting the flexibility, chemical incompatibility of the glue, the nature of PVC or something else entire, I don’t know. I was very cautious to not scorch the pipe in the original heating phase and there were no discolorations indicating otherwise. However, I did eventually come to resent this bow for its poor performance, hence its relegation to a ring tester. I pulled the string with little mercy and left it strung perpetually. But it didn’t buckle. It snapped.
In the beginning of my entry into archer not long ago, I couldn’t afford a bow. It is for primarily for this reason that I began making PVC bows. Admittedly, I did enjoy the pursuit of making these bows and the learning involved. I also enjoyed giving to other people curious about archery. In at least one case, this resulted in a serious interest in archery and an eventual purchase of a proper bow.
I doubt I’ll make additional bows from PVC, especially after this breakage. I’m not one to claim luck when something undesirable happens but could have been worse. But call it what you will, I was entirely unscathed, minus losing my testing bow, which isn’t exactly what I think of as fine fortune.