Tips on caring for your nyckelharpa bow

by Bart Brashers

Re-hairing your nyckelharpa bow can be quite an experience. The hair gets worn out eventually, and ceases to hold onto the rosin dust that does the actual work of making the string vibrate. It’s a heat-induced change in shear stress of the rosin that does the trick. As you pull the bow across the string, the frictional heat causes the rosin crystals to shear apart at a reasonable amount of force. That amount of force is just enough to pull the string a little from its resting position. When the rosin shears apart, the string is freed and its tension tries to return it to its resting position. Of course, it overshoots and the vibration is started. Since heat plays a factor in this process, we shouldn’t be surprised when we think our nyckelharpas sound or play differently on cold days.

As the hair on your bow wears out, it can’t hold on to the rosin as well. This also happens when the bow hair is dirty. Your hands have a certain amount of oil on them, and it eventually gets on the bow hair, and that collects dirt. You should wash your bow hair at least once a year, using warm water and dishwashing detergent. Loosen the bow, and gently rub detergent into the hair, working it in deeply. Rinse very well, and wipe dry the wood of the bow. Loosen the bow greatly and let it air dry, and reapply rosin. You’ll be amazed at how much better it sounds, and how much less rosin you have to use.

Eventually though, you’ll have to replace the hair on your bow. I used to replace it every year, but on the advice of Esbjörn Hogmark, I just started washing my bow hair more often. When you do need a re-hair, go to your local violin shop and tell them you have a special project for them. Bring along your harpa and play them a tune, so they get to know what kind of sound it produces (and get a little free entertainment). Many bows have wooden frogs, which most Swedish nyckelharpa makers prefer because they are so easy to make. If you can’t convince them to make a new wooden frog, dissecting the old one if necessary, you can use a violin frog instead. They are usually made of black plastic or vinyl, and usually fit pretty well. You might have to have them shave down the part of the bow where the frog slides, but that’s a reasonably easy job. Then, next time you need a re-hair, you can re-use the same frog. A re-hair should cost around $30, a bit more if you have to buy a new frog.

Playing with new bow hair is like walking down the sunny side of the street and suddenly finding you can sing after all. It takes less work to get the same amount of sound out of your harpa, and you’ll find you have a lot more control of dynamics and attacks. Give it a try!