When to Consider a Bow Rehair: Key Reasons?

As string players, we often give our instruments and their accessories—like our bows—little thought until they stop working as expected. The bow is a crucial part of your playing setup, and just like any tool, it can wear out over time. If you’re noticing your bow’s performance reducing, it might be time for a rehair. Here are three common reasons why a violin, viola, or cello bow may need a rehair:

1. The Hair Has Stretched

Over time, the hair on a bow can stretch with use, especially with frequent playing. A bow is tightened to a certain tension to ensure proper contact between the bow hair and the strings. If the hair has stretched excessively, it becomes impossible to tighten the bow to the correct playing tension. This is normally evident with a screw/adjuster that will no longer turn (do not force your screw/adjuster if it gets stiff or stops turning). When this happens, a rehair is necessary to restore the bow's ability to be used effectively.

2. Loss of hair

Regular use and the physical demands of bowing can cause individual hairs to snap, leading to a situation where there’s not enough hair left to properly grip the strings. If too much hair breaks, your bow won’t be able to produce a clean sound. Additionally, if the breakage occurs unevenly on one side of the bow, it can cause the bow to bend or warp, further affecting performance.

3. The Hair Becomes Worn and Less Effective

Even if the bow hair is intact, it can still lose its effectiveness over time. Bow hair has tiny "teeth" or “barbs” on it, which help each strand to grip the strings and produce sound. These teeth wear down gradually, which makes the bow less effective at gripping the strings, thus diminishing the sound quality and overall feel. This wear happens slowly, so it may not be immediately noticeable. However, after a rehair, you’ll feel and hear the difference—your bow will grip the strings more effectively, producing a richer, fuller sound. If you're playing several hours a week, you may need a rehair once every year to 18 months, depending on how quickly the hair wears down. If you’re playing professionally you will likely need a rehair every six months.

Prolonging the Life of Your Bow Rehair

While eventually, a rehair is necessary, there are a few things you can do to prolong the life of your bow’s hair and keep it in top shape for longer:

1. Loosen the Hair After Playing

Always loosen your bow hair after playing. While you don’t need to loosen it completely, aim to have the hair just touching the stick. This helps to relieve tension on the hair and prevent unnecessary stretching or warping.

2. Wash Your Hands Before Playing

You might not realize this, but your hands can significantly impact the condition of your bow hair. The oils, dirt, and moisture from your fingers/hand can transfer to the bow, especially around the frog (where the bow is held) and underneath the lapping. This grime can soil the hair and cause it to degrade more quickly. To help preserve the bow’s hair and the rest of the bow (including the frog and leather), wash your hands before playing.

3. Don’t Over-Rosin the Bow

Rosin is necessary for giving the bow hair grip on the strings, but it’s possible to overdo it. Using too much rosin can cause the bow hair to become brittle, making it more prone to breakage. The right amount of rosin ensures your bow grips effectively without overloading it. If you’re not sure how much to use, it’s always better to start with less and add more if necessary. For casual players, you might only need to rosin the bow once a week, while professionals may need to rosin before every practice session. Be sure to warm up first and gauge whether more rosin is needed.

Conclusion

A bow rehair is an essential part of maintaining your instrument, ensuring it performs well and produces the best sound. Whether the hair has stretched, broken, or simply worn out, getting a rehair is necessary to keep your bow in good working condition. By following a few simple tips, like loosening the hair after playing, washing your hands, and using the right amount of rosin, you can prolong the life of your bow and get the most out of your rehair. Not only are rehairs needed in and of themselves, it also gets your bow in the hands of a professional restorer on a regular basis for a check up which is never a bad thing.

If your bow is starting to feel unresponsive, it might be time for a rehair. Your bow will thank you, and so will your sound!