How Your Bow Tip Can Fail You

As you play your stringed instrument, you might not be thinking about how fragile your equipment is. My advice is to not think about this in performances. In every bow lies an area that can fail in many ways. If this area does fail, you can have an interruption in your performance, a big repair bill, or a new garden stake. I'm talking about the tip of your bow, where the stick gets thin, and the hair is held by a tiny chunk of wood.

You might notice that on my post Five Funny Fiddle Fails, that 3 of the failures were bow related. Given how bows are put together, its a wonder that any given orchestra concert doesn't feature at least one major bow fail. Your bow is a peculiar mix of the fragile and robust. It is strong in the right ways to withstand several pounds of tension on the hair, not to mention the beating that players inevitably dish out on the delicate stick. It can, however break for no obvious reason. Let's look at some ways that one little area of your bow can let you down.

Hair popping out of the tip is probably the most common and dramatic fail. it usually makes a nice little popping sound with hair flying all over. After all, if you fail, you might as well fail big, right? Here are the big three ways the tip can fail: the plug can come out, the hair bundle can come loose, or the tip plate can break.

A plug can fail if it is cut improperly or from inferior wood. The front of the plug should press the hair against the front of the mortise, and not be able to turn out. See the cut away view of the tip below: there is no room for the plug to turn counter-clockwise out of the mortise. It is like a car along the curb with other cars too close on the front and back. No matter how hard you turn, you will never get out without scraping your bumper. An improperly cut plug may have room to turn, and soft wood can simply crumble, thus leaving the plug able to turn out of the mortise.

Cut away view of the tip

Another path to disaster is the knots coming loose. The bow hair is held in bundles at both ends. The hair can start to fall out one at a time, then as there are fewer hairs, the knot gets looser, and things really break loose. There are many different ways of making bundles, but some are just accidents waiting to happen. I use strong thread and super glue. This one used some rosin and a flame along with a loose knot--not the strongest. There isn't much you can do if the hairs start to fall out like this. If this does start happening, don't pull them out, since it will make the problem worse. Just get it rehaired.

One of the most common issues with the bow tip is the tip plate--the white plastic or bone (sometimes metal) that covers the face of the tip. This plate gives valuable strength to the wood and takes some of the stress of holding the hair in. These can detach from the tip or they can crack. If it does crack, it should be evaluated by a professional to see if replacement is necessary. Very often, problems start with small cracks right beside where the hair comes out. Such cracks can be glued in place, and the bow will still work. In any case, it needs to be strong and stable, or else you risk the hair popping out or damaging the tip of the bow. A drop in a hard floor can also do a number on this piece.

Cracked tip plate: Note the small crack on the top right corner of the hair.

Another dramatic (and sometimes tragic) fail, is the head breaking off. This can happen if the bow has been dropped, and some micro cracks formed in the head. Extreme dryness is a double whammy for the head. When the wood dries out, it gets weaker. In addition dryness makes the hair contract, and if it is not loosened accordingly, it can pull the head off. As a last resort, you should cut the hair off. If the bow is above playing tension, and it will not get any looser, it's time to sacrifice the hair for the welfare of the bow.

Sometimes, there isn't much you can do about your bow failing. Even a bow rehaired by a really good technician can fail. If it does the shop should make it right for you, but no one is going to be quite perfect.

For musicians, the best thing we can do is to avoid abusing the delicate tip. This includes not dropping the bow, and not tapping or hitting anything with the tip. Those physical shocks can damage the tip plate, or jar things loose no matter how well it is put together. These shocks can also weaken the wood of the stick and increase its chances of breaking in the future. It is well to also avoid extremes of temperature and humidity. Wood expands and contracts with climate variations, and that movement can push things apart.

Bows are not that high maintenance, and taking care of one is not exactly rocket science. I hope that by shining light on these types of failures, I have inspired you to better respect the fragility of bows, and that you will better understand the mechanics and structure of your bow.