fret

Synopsis

This summarizes the technical analysis of a defect observed in a guitar manufactured at the Lâg Guitars Tianjin factory in December 2021 and sold by a Montreal guitar store in March 2026. The purpose of the analysis was to determine how the defect came to be, and in particular whether the cause was some random event, or rather some systemic deficiency likely to exist in other Lâg guitars. The analysis identified systemic manufacturing failures of concern to anyone owning a Lâg guitar manufactured since 2015:

  • owners who have already experienced structural problems and may have been told - or incorrectly assumed - that the cause was inadequate humidity management on their part.

  • recent buyers of Lâg guitars, whose instruments may develop issues over time even if they appear fine right now

The defect

While restringing a new Lâg guitar, the author noticed gaps under some frets. Upon closer examination he realized there were gaps beneath every one of the guitar’s 20 frets. All the frets were bowed such that their centers were raised while their ends remained flush with the fretboard (i.e. gaps were zero at the fret ends, and greatest at the fret centers). The center gaps ranged from 0.005" to 0.009". Although the gaps varied, they were not random: they occurred in a clear graduated pattern along the length of the fretboard ... moderate gaps at the lower frets, maximum gaps at the mid-neck frets, and minimum gaps at the upper frets. The mid-neck gaps were large enough to cause buzzing of the strings.

The analysis examines all of the possible causes of the gaps, and concludes that the only one consistent with the observed gap pattern, is shrinkage of the fretboard. Moreover, the analysis further concludes that shrinkage was not due to incorrect humidity management by the dealer, but rather to a combination of defective fretboard material, and inadequate humidity management in manufacturing.

Low-cost unconventional material

Lâg Guitars does not use natural woods for its fretboards. Rather, they use a low-cost engineered wood product trademarked under the name “Brankowood”, manufactured by Green Wall Technology Co Ltd of Jiangsu province, China. Lâg Guitars has used Brankowood for all of its fretboards since 2015, marketing it as an ecologically responsible alternative to traditional instrument woods. More recently it has also been using Brankowood for the tops of some of its guitars.

Guaranteed not to shrink

Lâg Guitars’ website describes Brankowood as pine that has undergone a complex multi-stage process they call “tropicalization”. The process steps most relevant to the observed defects are the impregnation of the pine with resin, and the subsequent application of heat to cure it.

Lâg Guitars describes Brankowood’s properties in unequivocal terms:

  • "The tropicalization process of the Brankowood guarantees a stable wood that's resistant to humidity and temperature changes."

  • Brankowood is a “totally stable wood […] which is not only perfectly resistant to changes in humidity and temperature but also to UV radiation and even termites”.

Assumptions vs. reality

In other words, Lâg Guitars believes Brankowood to be non-hygroscopic (i.e. impervious to changes in air humidity), and consequently dimensionally stable, as opposed to the traditional woods it replaces, which are hygroscopic (i.e. absorb and release moisture) and consequently swell and shrink with changes in humidity.

The apparent shrinkage in the subject Lâg guitar is entirely inconsistent with a dimensionally stable material, and entirely consistent with the behaviour of a conventionally hygroscopic one. The Brankowood fretboard clearly failed to behave as the stable material Lâg Guitars believes it to be. The most likely reason for the failure is that the Brankowood did not achieve complete resin cure during its manufacture at Green Wall.

Other guitars

Whether or not that failure extends to all Lâg Guitars fretboards since 2015 cannot be determined on the basis of this guitar alone. All we can know for sure from this guitar is that:

  • Green Wall’s quality control program failed: if it had detected either the defective (hygroscopic) product, or the significant deviations in process parameters that would have caused it, this guitar’s fretboard would never have left their factory.

  • all Brankowood from the same Green Wall factory batch as this one would have been similarly hygroscopic, because the entire batch would have experienced exactly the same deviations in process parameters as this one.

The moisture problem

Hygroscopic behaviour on its own is not enough to account for the fretboard shrinkage and consequent fret damage witnessed on this guitar; after all, conventional fretboard woods are all naturally hygroscopic, and they don’t end up deforming the frets on a brand new guitar. Rather, the observed defects also require that the fretboard blank had significant moisture content at the time it was fretted, and was subsequently stored in a relatively dry atmosphere. In other words, either…

  1. Green Wall and Lâg Guitars maintain Brankowood in an industry-standard 45-50% Relative Humidity (RH) atmosphere, but the eventual guitar dealer failed to maintain that same RH in his showroom, or

  2. At some point prior to its having been fretted, Green Wall and/or Lâg Guitars exposed the fretboard blank to an atmosphere significantly higher than the industry standard 45-50% RH.

Dealer negligence?

The argument that Lâg Guitars would most likely push is that the dealer failed to maintain adequate humidity control in his store. This explanation is not supported by the evidence. The dealer's showroom humidity was maintained at 45-50% RH, consistent with industry standards for instrument storage, as witnessed by the author. Moreover, even if the dealer had failed to maintain the correct humidity, Lâg's argument would presuppose that all guitar components — including the defective Brankowood fretboard — had been conditioned to the same 45-50% RH before assembly. Had that been the case, all components would have shrunk together when exposed to drier conditions, and the result would have been uniform gaps along the neck — not the graduated pattern observed here.

Follow the money

A much more credible explanation becomes apparent when one considers the full economic implications of an assumed dimensionally stable material — implications that go far beyond just Brankowood’s low cost.

A truly non-hygroscopic material does not require expensive humidity control systems in its storage and work areas, nor does it require time-consuming checks of moisture content at various stages in the manufacturing process. Lâg Guitars would have had such systems and checks in place for the traditional fretboard woods it was using prior to 2015, but would have realized that replacing real wood with “guaranteed stable” Brankowood rendered such systems and checks entirely unnecessary.

Lâg markets its guitars as high value-for-dollar instruments, and sells them at extremely competitive prices; the idea of Lâg Guitars maintaining costly environmental control systems and verification procedures for a material they believed did not require them, is very difficult to reconcile with their business model. It is therefore reasonable to conclude that Lâg Guitars relaxed or altogether abandoned its traditional fretboard controls upon adopting Brankowood in 2015.

The factory blind spots

The Lâg Guitars factory would handle its natural woods traditionally, keeping them in areas maintained at the correct 45-50% RH, and monitoring their moisture content. Brankowood components however would be handled differently:

  • Green Wall, confident in the dimensional stability of their product, would have no concerns about exposing it to excessive humidity, whether in their processing areas, their warehouses, or their trucks. Incompletely cured stock could therefore absorb excessive moisture at any time between its processing and its reception at Lâg Guitars’ factory.

    In a guitar factory using traditional tonewoods, incoming material is checked for moisture content, and handled accordingly. But Lâg Guitars presumably dispensed with those checks for Brankowood stock when they switched to Brankowood in 2015, thereby creating a quality assurance blind spot in which an incompletely cured, excessively moist shipment of Brankowood would be undetected.

  • Similarly, the presumed post-2015 absence of a controlled humidity environment in Lâg Guitars’ fretboard areas would leave Brankowood stock further exposed to RH levels in excess of 45-50%. Moreover, the absence of traditional quality control checks prior to fretting of the Brankowood blanks creates a second quality assurance blind spot similar to the first.

The gap pattern says it all

In the end, defective and excessively moist Brankowood would be undetected throughout the entire guitar manufacturing process, invisible and latent until the slow process of moisture equilibration in the dealer’s correct 45-50% RH environment ran its course, slowly shrinking the fretboard and eventually deforming the frets.

On the other hand, the neck and body of the guitar, their moisture content having been traditionally controlled throughout the manufacturing process, were already at equilibrium with the showroom’s 45-50% atmosphere when they entered it, and so would not have been drying along with the fretboard that was glued to them; consequently they would have constrained the fretboard's shrinkage, resulting in exactly the graduated gap pattern observed in this guitar; the graduation in gap size mirrors the variation in stiffness of the overall neck assembly — from headstock through neck shaft to heel, neck block, and guitar top.

The observed pattern therefore confirms both hypotheses — that of the defective Brankowood, and that of Lâg Guitars having abandoned its traditional fretboard controls in 2015.

The irony is pointed: if the Brankowood in this guitar had performed as assumed, none of this would have happened; if Lâg Guitars had maintained their pre-2015 fretboard controls, none of this would have happened. The gap pattern is a direct measure of both the degree to which the Brankowood fell short of its assumed properties, and the degree to which Lâg Guitars believed it never would.

The pandemic and the time delay

The manufacturing and sales dates of this guitar provide additional insight into the risks inherent in Lâg Guitars’ full exploitation of Brankowood’s cost benefits …

  • The guitar was manufactured in December 2021 — at the height of the pandemic’s surge in demand for guitars, and during China's zero-COVID operational disruptions. Green Wall would have been under extraordinary pressure simultaneously on both the supply side (eg disruptions in supply of resin required for its process), and the demand side (ie Lâg’s need for enough fretboard stock to satisfy the surge in demand for its guitars). Green Wall production was therefore particularly vulnerable to the variability in execution of its Brankowood process and the deficiencies in its quality control measures, with a consequently increased probability of defective Brankowood being supplied to Lâg Guitars.

  • The guitar was sold in March 2026 — four years and three months after it was manufactured. That is an extraordinarily long period, and is no doubt the reason why the defect was noticed so soon by the author. Had the guitar been sold earlier, say within a year or two of its manufacture, the fretboard may not yet have had enough time to equilibrate hygroscopically and there would not yet have been any apparent gaps beneath the frets; shrinkage would have instead continued in the author’s home - even at 45-50% RH - with additional months or years passing before the gaps would become apparent. A clean inspection at the store is therefore not a clean bill of health for a Lâg guitar with a Brankowood fretboard.

Systemic defect

The analysis therefore concludes that the root cause of the fret gaps is indeed systemic, and is therefore likely to have caused similar damage in other Lâg guitars manufactured since 2015. Defective Brankowood looks fine when it leaves the Lâg Guitars factory, but its unmonitored moisture content may be extraordinarily high, and so it subsequently shrinks over time — even if maintained at the humidity level normally specified for guitars — and eventually damages the frets.

The time-dependent nature of the defect has direct implications for three groups of people: prospective buyers of Lâg guitars, who should be aware of these risks before buying one; recent buyers of Lâg guitars, whose instruments may develop fret issues over time even if they appear fine right now; and existing owners who have already experienced such problems and may have been told - or incorrectly assumed - that the cause was inadequate humidity management on their part.

The analysis also identified a systemic risk to glue joint integrity in Lâg’s Brankowood guitars, but that is a separate topic to be addressed in future.