Q: I’ve a 1958 Martin D-28. Throughout a current restringing, I observed the tuning gears (Grover Rotomatic 102C) had all types of black goop inside, trying like lubricant previous its service life, once I eliminated the tuning button from one of many gears. I’m questioning if after 63 years of fine service these gears would possibly want cleansing, relubrication, or repacking. I’ve learn somewhat about it and have been warned off utilizing Vaseline and seen that Tri-Flo Superior Dry is really useful by some. What would you employ for lubrication to renovate a Rotomatic? —Bob Metzger

A: To start, let’s take a fast have a look at the principle elements of the mechanism: the “worm” gear (the spiral-shaped part that connects to the deal with/button) and the pinion gear (the spherical half that turns the string publish). Almost all guitar tuners function on this similar mechanism, with extraordinarily few exceptions, most notably Ned Steinberger’s linear-drive “gearless” tuners and Invoice Rickard’s current and really modern design involving a cycloidal drive system.

Many classic guitars, and the fashionable devices that emulate them, could have open-back or exposed-gear tuners. Because the title suggests, these tuners give an unrestricted view of the worm-and-pinion association. This additionally signifies that these gears are inclined to amassing mud, case lint, and some other particles or fluff that will occur to come back alongside. If particles builds up within the gear tooth, it might probably trigger sticky and unreliable tuning and probably even gear failure. For that reason, I usually use a dry lubricant on open-back tuners, quite than a paste grease or different sticky lubricant that might collect contaminants. I’ve had reasonable success with powdered graphite, however currently I exploit Tri-Circulation for open-back tuners, on the recommendation of the good repairman and tuner connoisseur Frank Ford. Though this dispenses as a liquid oil, it really works primarily as a provider for microparticulate PTFE (aka Teflon), which adheres to the gear surfaces and continues appearing as a lubricant even after the oil itself has dried.

When lubricating open-back tuners, I usually take away the strings, which permits me to show the tuner freely in each instructions. I apply a small drop to the purpose of contact between worm and pinion, after which use a string winder to show the tuner pretty shortly. After a few 1/3 flip of the pinion gear (normally three to 5 turns of the deal with), I apply one other drop on the similar contact level and repeat once more after one other 4 or 5 turns. Then, I flip repeatedly to maneuver the pinion gear by way of one other full rotation. This usually leaves a pleasant, even layer of lubricant across the perimeter of the gear, with out making an excessive amount of of a large number. Preserve a cotton swab available for any stray drops of oil that drip out.

Fashionable cast-body or sealed tuners are a distinct story. Up to now, cheap tuners have been recognized for low high quality steel and poor manufacturing tolerances, and have been incessantly guilty for unstable tuning. Firms resembling Grover, Schaller, and Gotoh addressed this by providing tuner upgrades with higher gears, tighter tolerances, and totally enclosed our bodies, which allowed the gears to show in a shower of thick paste grease. These tuners have been designed to be completely closed, and in lots of circumstances they nonetheless carry out admirably after many years of maintenance-free service. Nonetheless, the small disc or plate that seals the again cowl can fall out and be misplaced, exposing the gears inside, and permitting the grease to gather contaminants. 

In these circumstances, I’ll disassemble and clear the tuner as greatest I can. A heated ultrasonic cleaner is the popular software for this in my store, however a less complicated answer is a short dip in boiling water adopted by a scrub with an previous toothbrush. Subsequent comes reassembly and relubrication with a midweight grease. Blue or blue-green lithium-based greases usually work effectively for this, and people with added PTFE are even higher, however even fundamental white lithium grease from the ironmongery store will normally be positive. I don’t overpack the gearboxes—only a affordable dollop is ample. Then, substitute the again medallion to surround the gearset once more. If you happen to can’t substitute the medallion, think about the dry-style lubrication strategy as an alternative (as detailed for open-back tuners) utilizing Tri-Flo.

The third frequent household of tuners makes use of a stamped sheet-metal again which covers the worm and pinion. Among the many manufacturers that produced these, one of the best recognized was Kluson, whose tuners have been discovered on Fender guitars for many years, in addition to on many acoustics. These tuners usually have a small gap within the again plate, which is supposed to permit lubrication on the strategic level the place the worm and pinion intersect. This gap can even let in a stunning quantity of mud/grime, as I’ve found in some circumstances once I disassembled older units. If the tuner feels a tiny bit gritty or tight, a drop of oil by way of the opening ought to be ample. If it feels worse than that, I normally do an intensive disassembly and cleansing.

Since we’re discussing tuner upkeep, I’ll additionally point out one other quite common concern that comes up with classic tuners: rotten or cracked plastic buttons. Many classic tuners undergo from this concern, and I’ve dealt with a variety of guitars whose buttons merely cracked off when turned. This is because of long-term degradation of the plastic used for the buttons. There isn’t a actual sensible repair for this aside from changing the buttons. Most provide homes, resembling StewMac, promote melt-on buttons meant for this goal. After the tuner shaft has been cleaned of all previous plastic and oxidation, the tech can warmth it up utilizing a flame or soldering iron (I want the iron, because the flame can typically go away a black deposit) and press the button into place, molding the plastic across the shaft of the tuner. When all the things cools, the button is solidly collectively.

One final observe: Most tuners have a bushing (steel sleeve) that installs within the face of the guitar’s headpiece to help the string publish. This merely presses into place on older tuners. On newer cast-body tuners, the bushing is threaded and screws by way of the headpiece into the tuner housing. The press-in ones are infamous for falling out at inconvenient moments when altering strings, and might disappear below tables or into crevices very simply. (Belief me on that one!) 

When working in your guitar, make certain the bushings are a decent match, or else put a plastic bag over the headpiece so any misplaced components will get safely caught. It’s additionally a good suggestion to examine the bushings on fashionable tuners periodically—they’re fairly often free, and typically the washers beneath them could cause mysterious rattles and buzzes which might be maddening to diagnose. Don’t crank them too exhausting as it might probably trigger issues within the surrounding end. Merely comfortable them up with an open-end wrench or socket. Almost each forged tuner round makes use of a 10mm wrench. When lubricating tuners, particularly older open-back fashions with press-fit bushings, I additionally put a tiny drop of oil between the string publish and bushing, on the 6 o’clock location the place the bushing is closest to the nut.

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