Winter Instrument Care
The Winter season can pose some dilemmas for the violin family instruments. The main concerns are extreme cold temperatures and low humidity. Once we start heating our homes and schools the hair on the bow shortens and the softer spruce tops will shrink laterally (across the width) at a greater rate than the hard maple back and sides. With a few steps of precaution, many problems can be eliminated entirely, or at least somewhat diminished.
I recommend a digital hygrometer to monitor the humidity of the main room where you keep your instruments. We attempt to keep our shop in the range of 38-42% humidity all winter. To achieve that we use up to two Bemis brand humidifiers in opposite corners of the room. I recommend monitoring the humidity year round to detect when it starts to drop. When the humidity drops to the low 30% the tops shrink laterally. The arching height will become lower, bringing the bridge string height nearer to the level of the fingerboard. Some cellos and basses require higher bridges or shims to raise the height if buzzing is a problem. The soundpost will be tighter during winter which will alter the voice. Instruments typically become brighter and edgey with more of a scratchy surface noise with each directional bow change.
Sometimes switching to lighter gauge strings helps to reduce these tendencies. Try exhaling in through the instruments f-hole a few times, then play it to see if you get a rich, clearer voice. This is a quick test that gives you an immediate result as to whether or not a Dampit will help. If you use a Dampit, be certain to thoroughly squeeze out excess water with a towel to prevent pooling on the backs of violins and violas and lower ribs of cellos and basses. If used properly, Dampits are an excellent way to maintain equalized plate widths. Recharging them every other day should be enough as wood takes on moisture faster than it releases it.
The hide glue used to attach the top should be the weakest strength used on the violin to allow pressure to release at a seam which will prevent a longitudinal crack if there are imbalances. A sign of an open seam or purfling separations would be a sudden drop in over all volume with the diminished tone quality occurring mostly in the lower two strings. As durable as the violin family instruments are, one thing they cannot tolerate is the rapid transition from a frigid mid 30 degree or lower outside temperature to a sudden rush of 68-70 degree heated inside air. Opening the case in this sort of condition can cause a rapid expansion of the top creating length wise cracks before your eyes. Try to arrive at your destination a bit early to let the instrument warm up gradually. Violin sacks, interior case blankets and insulated case covers help maintain the heat in the case as long as possible. Never place instruments in unheated car trunks.
More bows break in winter than other seasons. While playing under stage lights, periodically check hair tightness as the hair may shrink even more, causing the head of the bow to snap off on a strong down bow.
The first sign of the dry season is usually when the tuning pegs let go during storage. When you see the humidity dropping you can prevent this from happening by chalking the contact points on the peg shaft which creates friction. Rewrapping the string closer to the tapered peg wall will drive the peg deeper, making it turn tighter. The clear humidistat tubes in the scroll compartment of your case also helps prevents the pegs slipping. Once you've reset your pegs, always check bridge straightness as retuning will pull the bridge top toward the fingerboard. Apply soft pencil lead to the bridge notches prior to retuning to allow the strings to glide through the notches. Once you are finished with that, it would be a good time to check the reading on your digital hygrometer. It's the cheapest insurance you can buy.
Summer Instrument Care
Summer for the most part can be a problem-free time of year for the violin family. That is as long as temperatures are in the moderate 70°’s to low 80°’s, one can play outdoors with the same carefree attitude as when indoors.
The three main considerations for summer use, are high humidity (over 60 percent), excessively high temps (over 90 degrees F), and direct sun during the high temps. The high humidity will cause the hair on the bow to stretch up to 1/2". One needs to be alert to this condition, as the eyelet on the frog will be allowed to travel toward the end of the sticks channel. If you find the bows button will not turn or becomes tight, it could strip the button off the screw. This will be apparent when the space between the leather wrap and frog increases so much that it may become difficult to hold. It may be lime for a hair shortening or a rehairing.
Spruce tops swell to a wider dimension than the denser maple back and sides, which in turn causes the arching to rise. This brings the bridge up with it, resulting in a higher string action on the fingerboard. A lower summer bridge may be needed if playing becomes too difficult. The sound post fit will become looser, which will alter the voice, usually making it a bit duller. If one has an important performance, a summer adjustment may he necessary. Dark rosin becomes even stickier, creating a gritty, sandy halo around the voice. Switching to lighter, pale rosin will clear that problem up, as it is a harder formula. Pegs will not turn as smoothly and may jam tight, it's a good idea around mid-May to early June, to make certain there is a space between the wound string and the peg box wall. Most of the resins used to make varnish have softening points around 110 to 120 degrees F. By the time we get into late June to early July, the instruments varnish is already softer due to the higher humidity and may become tackier to the touch and can fingerprint. For this reason they should be handled by the neck and chinrest only. Rosin, which is softer than varnish resins, should not be allowed to accumulate as it can be absorbed into more porous varnish finishes. Rosin left on any violin will be completely adhered by the end of summer. Strong cleaners should be avoided in summer as it could remove the softened varnish as well as rosin residue.
Instruments are held together with water-soluble hide glue. Seams open more readily in high humidity. Tops are softer and more flexible in summer and edges will bulge if seams are left open. When not in use or while traveling in a vehicle, avoid storing cases where sunlight coming through a window can hit the case. The temperatures inside the case can rise high enough to blister the varnish. Of course never leave you instrument in a car during summer, even if in shade with the window open. It could still disassemble itself from the heat build up.
Lastly, if shipping instruments in the summer months, it’s a good idea to monitor the temps and weather trends in your local area, the route it will travel and its destination area. Avoid shipping during time frames with temps over the mid 80’s F and/or heavy rains forecasted. Even with good insulating materials, temps inside the shipping box will only be held down for approximately 1 to 1 1/2 hours while in transit. Avoid rainy periods, as you'll never know if a shipping terminal floods or a delivery truck leaks.