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Straightening a violin bow

Q: What is the correct way to straighten a warped violin bow?

Thanks, Tom DiCandia

A: New violin bows are cut straight and are then "cambered," or bent into their final shape. The best woods for bows bend easily. The traditional tool is the alcohol lamp, but I have found the best source of heat to be my kitchen stove. I fire up the biggest burner to a nice red, electric glow, and move the bow slowly back and forth over it. 2 to 4 inches from the heat is good. If the finish starts to bubble, move faster, or get farther from the heat. Wood bends by crushing cells. If you are bending a stick to the left, the wood on the left is getting shorter and the wood on the right is staying the same length. Hence, you only need to heat the left side, not both sides. If you have a long even warp, heat the whole, convex side of the bow. If you have a short kink, just heat that part.

When the bow is good and hot, bend it across your leg. Bend a little and sight down it. If you overbend, you have to correct by heating and crushing the other side. Try not to overbend. Blue jeans will protect your legs from the heat. Some people add an apron for a little more protection. Don't try this bare legged. Let the bow cool completely before use.

If the bow has hair on it this becomes a two man job. One person follows the above instructions, and the other holds the hair straight out from the tip of the bow.

A trick that I sometimes use in the summer is to put the warped bow in the back window of my car in the sunlight. After an hour it will bend easily. This bending in the sun is why many bows are warped in the first place. Lots of violin cases put some tork on the bow. Add a little summer heat and the bow conforms to the case.

Steve Mason