Slipping Peg Strife
Almost every bowed string instrument player has run into a problem with their strings going out of tune. Most of the time, this problem (on a violin, viola, or cello) is caused by a slipping peg.
In fact, when a customer walks into our store with a broken string, 9 times out of 10 the cause of the break was over-tuning of the string. This is an even more common occurrence when the peg has slipped dramatically out of place and the player (or family member, neighbor, or helpful friend) has attempted to retune an almost completely slack string.
Understanding the Pegbox
What many beginning players may not realize about violin, viola, and cello design is that traditional, wood pegs are held in place by compression. In addition to offering a lighter weight option than a set of metal gearheads (like those on an upright bass), the compression fittings of wood pegs make fine-tuning the instrument a very precise art.
The pegbox contains 4 sets of peg holes. Each set of peg holes is tapered to match the shape of each peg—the side of the peg closest to the peghead is thicker than the opposite, thinner end of the peg.
Each string is attached by threading the string into the peg, winding the string into place, and pushing the peg gently inward toward the pegbox when the string has reached its full tension.
Although they don't need replaced nearly as often as strings, pegs are a "consumable" item on a violin, viola, or cello. We use the different woods selected for the pegs (Ebony, Rosewood, and Boxwood) based on their ability to compress and break down over time.
It is better for the health of the instrument for the pegs to compress and wear out than to need to adjust, fill, or repair the pegbox which is a permanent fixture on (and important part of the value of) the instrument.
6 Common Causes of Slipping Pegs
We have compiled a list below of the most common causes for slipping pegs.
1. Low Humidity
This is the single largest culprit of slipping pegs in dry months and climates. Humidity is one of the most important things to maintain for your instrument (and bow).
To better understand this issue, imagine your home during humid, summer months—you may find it more difficult to close a bedroom door, but in the winter this same door is not a problem. Pegs go through very similar changes—high humidity can cause pegs to swell and stick in place and low humidity can cause pegs to shrink and lose their grip in the pegbox.
The Solution: Maintain 40-60% humidity for your instrument and bow. In dry months/climates, humidify your case (or store your instrument in a room with 40-60% humidity) and apply either Peg Compound, LAVA brand bar soap, or a combination of both to your pegs. The addition of a compound will help fill any minor, humidity-related gapping in the pegbox.
To apply compound:
Make sure to only adjust one peg at a time. Remove the string from the slipping peg and remove and examine the peg. There will be 2 shiny spots on the peg where the peg is regularly making contact with the pegbox.
Apply a thin line of Peg Compound/LAVA bar soap around the peg on the shiny spots where the peg makes contact with the pegbox. Return the peg to the pegbox, turn the peg a few times to work the compound/soap in, and re-install the string.
PSA—Keep pegs drops, chalk, and rosin away from your pegs! The extreme hold these items have on pegs is dangerous. We have seen countless frozen or broken pegs/scrolls due to the use of chalk, rosin on pegs, and peg drops. Their benefits do not outweigh their potential for damage and the cost of Peg Compound or LAVA bar soap is miniscule for the amount of time you get out of either item.
2. The Instrument Received a Hit or the Case Took a Blow
This may be the most obvious cause of a slipped peg(s)—accidentally bumping your scroll on your music stand or having someone trip and kick your case can cause the pegs to lose their hold in the pegbox and unwind.
The Solution: Try to avoid collisions and take protective measure by storing the instrument in its case whenever possible and store the case out of the way of foot traffic.
In the event an accident does happen, bring the instrument in for a free check-over to make sure nothing major happened like a scroll crack happened in the jostle. Scroll cracks are more common than you'd think!
3. Out of Round Pegs
Normal tuning can cause pegs to compress and go out-of-round. A peg that has gone out of round will be resistant to tuning, even after application of LAVA soap/peg compound.
The Solution: If you suspect your peg(s) is out of round, bring the instrument in for inspection and peg adjustment or replacement. Luthiers have special tools (and the skills necessary to use them!) which can be used to correct the taper on pegs and pegboxes.
4. The String Hole is Too Close to the Pegbox Wall
As we just mentioned, normal tuning can cause pegs to compress. As pegs compress and progress further inward, the string hole moves closer and closer to the scroll. Eventually, the string hole will get too close to the scroll and the peg will no longer be able to easily fit into the pegbox.
The Solution: Provided the peg is still otherwise functional, bring the instrument in to have a new string hole drilled into the peg. This is often a quick solution and can happen while you wait.
5. The String is Wound Too Close to the Pegbox Wall
Sometimes when a string is installed onto a peg (or retightened after going slack), the string is wound too close to the pegbox wall. This can cause the string to become trapped or cause it to act as a wedge between the peg and the pegbox which ultimately pushes the peg back out of the hole.
The Solution: Rewind the string on the peg, taking special care to leave space between the pegbox wall and the edge of the string winding.
6. The String is Making Contact with Another Peg
This problem is more likely to happen on the strings further up in the pegbox (for violin E, A, or D and for viola/cello A, D, G). This problem is caused by pegs that are out of alignment and one or more pegs is placed too high or too low in the pegbox. A peg located too high can reduce the clearance for strings whose pegs are further up in the pegbox.
For example, if the D peg of a violin is located too high up in the pegbox, the A string will make contact with the windings of the D string (or the peg itself) and will be unable to stay in place.
The Solution: Bring the instrument in to see if we can make a small adjustment to your existing pegs or discuss bushing and repositioning your pegs to correct the problem.
This list is not exhaustive of all of the problems which can cause pegs to slip.
If you are still running into problems or are having a hard time diagnosing your current problem, don't hesitate to stop by for a free evaluation!
Posted on: 15th March 2016
Updated: 24th March 2023