Here’s Why Your Violin, Viola, or Cello Bow Is Warped (and How to Prevent It)

Some string players say a little bow warp is A-OK. Read a few violin forums, and you’ll find that some people believe a “bend to the left [is] good, to the right bad.” Other players add that if the bow plays just fine as-is, there’s no need to adjust slight warping. What do you think? Are these string players right or wrong?

The answer to what to do, if anything, with a warped violin bow isn’t black and white.

Good Bow Bend vs. Bad Bow Warp

Bows are designed to be inherently curved but never twisted or crooked.

“The modern bow has a curve towards the hair ribbon, the camber,” explains Jan James in Practical Acoustics of Instruments of the Violin Family: Bridging Science and Art.

To attain this curve, “the shaft is heated thoroughly, equally and evenly on all sides and then bent while hot…if everything has been done optimally, the ‘belly’ of the stick touches the hair about halfway.”

How can you tell if your bow is perfectly bent or leaning toward broken?

Take it from James, a scientist and former Professor of Histology at the University of Amsterdam, who has been interested in the acoustics of violins all his life. In his book, he suggests evaluating warp by starting with a “gun barrel view” of the bow and looking from the handle to the head of the bow.

“Some lateral deviation to the left for a violin or viola bow and to the right for a cello or bass bow (i.e., contrary to the direction in which force is exerted in playing) is favorable… The lateral deviations just mentioned (when in the right direction) make the ‘feel’ of a bow somewhat stronger; there are, however, also good bows which are totally straight, apart from the camber. A lateral deviation in the wrong direction, however, should always be corrected.“

You can also gently set the bow hairs flat on a table and look vertically down at the wood and hairs. The wood should be positioned above the hairs right along the whole length.

Whether your bow is badly warped or just started to bend in a new way, take your bow to a luthier or consider buying a new one if the warp impacts your ability to play or causes you to change how you’re playing to account for the warp.

How Do Violin, Viola, and Cello Bows Become Warped?

Excluding camber here (or the bow’s inherent and intended bend), how does a bow become badly warped or bent, a.k.a damaged?

Humidity or Dryness

In humid climates, moisture in the air can cause a bow to droop and the hairs to loosen. The strands can draw up and tighten in drier climates, causing the bow to bend upward. Moisture, or lack thereof, primarily impacts wood bows. Carbon fiber bows don’t expand and contract in heat and are less likely to warp when exposed to moisture.

Excessive Broken Hairs on One Side

Bow hairs don’t last forever. A few broken hairs are no cause for alarm, but too many on one side can cause uneven tension and warping.

Poorly Done Rehair

Too much hair, too little hair, uneven hair–a poorly done rehair sounds terrible and can lead to bow warping.

You Often Forget to Loosen the Bow Hair

One of the first things you learn as a new string player is to release the tension on the bow after each practice or performance, as the stress can eventually warp it or cause the head of the bow to break off.

Constant tension isn’t so much a problem with carbon fiber or fiberglass bows, but if you have a wooden bow and leave the string tight all the time, the bow may warp.

How to Prevent a Warped Violin Bow

The best advice for preventing a warped violin bow is to maintain it properly!

• Don’t put off a proper rehair.
• If a bow hair breaks, carefully clip it off with fingernail clippers or scissors. Do not pull it out, as doing so could damage other hair strands and lead to uneven tension.
• Don’t tap or bang the head of your bow on anything. (There are better ways to get someone’s attention!)
• Always loosen the bow after playing.
• If made from wood, keep the bow in a temperature-controlled environment.
• Clean your bow hairs and stick to minimize rosin and dirt build-up.

One of the best ways to prevent a warped bow is to avoid the situation altogether! Consider retiring your wooden bow for a carbon fiber bow, which is far sturdier and more reliable than wood. Carbon fiber is actually five times stronger than steel and twice as stiff. It also has high stiffness, tensile strength, and temperature and chemical resistance. So is playing with a carbon fiber bow like playing with a chunk of unforgiving metal?! Hardly!

“Wood is extremely variable, but carbon fiber is not, so it’s possible to make bows that are very consistent in weight, balance, and feel,” explains the editor of The Violinist. Plus, carbon fiber bows won’t expand and contract in heat and warp from moisture.

Along with carbon fiber, CodaBow uses a proprietary blend of organic and composite material infused under high-pressure to achieve unrivaled timbre, overtones, and range. This blend allows the bows to boast superior quality beyond what is achievable with carbon fiber alone.

If your warped bow is not repairable or you’re ready for an upgraded bow, consider starting fresh with a carbon fiber bow. Shop violin, viola, and cello bows for all musician levels online or at a CodaBow retailer near you.

Common Warped Bow FAQs

Q: How do you straighten a warped violin bow?
A: We do not recommend trying to straighten a warped violin bow at home. Straightening a warped bow involves applying heat and pressure; too much of either can break the bow or cause irreparable damage. Consult your local luthier.

Q: Can a warped violin bow be fixed?
A: Maybe. It depends on the severity of the bend. If it’s only a slight warp, there should be little risk in having it fixed by a professional. Also, check that there aren’t a ton of broken hairs on one side. Unbalanced hair tension could cause the bow to deflect. Getting your bow rehaired could also fix the warp.

Q: How can I tell if my violin bow is warped?
Hold the bow up to one eye. Look down your bow (from frog to tip) like you’re looking down the site of a gun. Close one eye. The stick should be straight.