Homer J. Simpson
Well-known member
I love to point out how exactly "golden era" Tokais are different from their role models and contemporaries, also because the majority of internet debates about quality and value are very unspecific. When I got my TE70 I noticed the neat fret end treatment, I had seen this before on some other (Japanese) guitars in the past decades, I even owned some of them but I didn't waste much time to understand what I was seeing there. It felt good, end of story.
Sigmania's ST70MG: "Slab" fretboard with "semi-hidden" tangs
Seeing this again on my new old Tokai and being curious how consequentially Tokai applied this treatment to the guitars, I realized how this is not a pretentious "nice to have" complication but a technique to seriously improve the feel of a neck, and more than anything else to mitigate the detrimental effects of dry environments, a.k.a. "fret sprout".
How most F-style guitars get their frets (and why that isn't always great)
Fretwire cuts are pressed (or hammered) into the fretboard, the surplus fret length sticking out will be pinced off and then filed down to the fretboard edge. Here's a 1997 Fender factory video showing the beginning of the process:
This method requires very strict "moisture content management" in the factory: If the "equlibrium moisture content" in the wood during the fret dressing process is higher than the lowest equilibrium moisture content to be expected in climates where the customer plays and stores his guitar, the fretboard (or just the neck on one-piece maple necks without separate fretboard) will shrink. The metal frets won't, so they start sticking out of the fretboard and expose their sharp edges and burrs. But if both the fret crowns and the tangs extend to the very edge of the fretboard due to this simple fretting method, there is inevitably zero margin for wood shrinkage*.
* "That's what she said"
Custom Shop Telecaster showing how the fret tangs reach to the fretboard edge
Better than beating you around the head with technical woodworking terms is showing you some scary pictures! Here's an example where "fret sprout" didn't even happen yet, the fret tangs were simply not properly filed all the way down to the (strangely rolled) fretboard edge:
Protruding fret tangs on a 2022 Telecaster (MIM)
Here's what happens when real fret sprout hits the finish on a maple neck:
Fret tangs pushing the finish off the wood after wood shrinkage (MIM Strat)
The Japanese "hidden tangs"
First off, I don't know where this method was really invented, and it wasn't used by Tokai only: Many if not most of the more ambitious Japanese factory guitars made in the second half of the 70s featured this kind of fretwork. Secondly you may think that they needed to do that due to the humid climate in Hamamatsu - but Hamamatsu and L.A. are both on the 34th parallel north and the relative humidity seems pretty comparable over the year:
Relative humidity in the Kanto region (blue) vs. SoCal (amber)
So what were they doing different? In one sentence, they were cutting the frets, particularly the tangs shorter than the fretboard width, then filled up the fret slots with putty, shellac or simply finish to "hide" the tangs:
Nicely rolled TE70 bass-side fretboard edge with filled fret slots
Alas I don't know how exactly that was done in the Shōwa era, either the frets were cut to precise length before inserting them (or even ordered pre-cut from Sanko), or the fretwire pieces were only undercut ("nipped" tangs) and the surplus crown material sanded down after insertion.
"Nipped" fret tang
Modern day factory images show a belt sander and a worker apparently creating the crown bevel:
Long belt sander in the Onchi-cho factory 2012
Here's an image trying to show why this is nice - the pic was taken straight from above even if it looks it was taken from an angle - it shows how the fret crown does not extend beyond the rolled fretboard shoulder, as if the neck was bound:
Why I wanted to show this is that they obviously went that extra mile to make sure that the necks feel good and fret sprout will never be a thing on these guitars, or at least not a big one (which is when the fret tangs are sticking out, a bit more of a PITA to fix).
Unlike the Ensenada-Fenders shown above, the nicely rolled edges are not disturbed by the fret ends having a different radius and extending a bit beyond the edge. The edges are really nicely rolled, for some reason a bit more intensively on the bass side than on the treble side on my guitar. They sure felt already "broken in" and comfy like typical vintage originals when the guitar was new and not a vintage guitar itself.
Fretboard edge rolled at a time when "rolled fretboard" wasn't really on everyone's lips yet
Since I've seen pretty varying degrees of edge rolling on Tokais, I assume that the amount was at the discretion of the worker doing this that day, just like in the old Fender Fullerton factory. This kind of treatments certainly came with a little bit of a time penalty and higher skill requirements, and it was applied to all guitars, not only the pricier ones:
Lower grade (simple tuners) Limited Edition guitar
Besides the nice feel - should fret sprout ever happen on those guitars, it's a matter of a few gentle kisses with a fret end file or a short visit at your tech guy to handle this!
Sigmania's ST70MG: "Slab" fretboard with "semi-hidden" tangs
Seeing this again on my new old Tokai and being curious how consequentially Tokai applied this treatment to the guitars, I realized how this is not a pretentious "nice to have" complication but a technique to seriously improve the feel of a neck, and more than anything else to mitigate the detrimental effects of dry environments, a.k.a. "fret sprout".
How most F-style guitars get their frets (and why that isn't always great)
Fretwire cuts are pressed (or hammered) into the fretboard, the surplus fret length sticking out will be pinced off and then filed down to the fretboard edge. Here's a 1997 Fender factory video showing the beginning of the process:
This method requires very strict "moisture content management" in the factory: If the "equlibrium moisture content" in the wood during the fret dressing process is higher than the lowest equilibrium moisture content to be expected in climates where the customer plays and stores his guitar, the fretboard (or just the neck on one-piece maple necks without separate fretboard) will shrink. The metal frets won't, so they start sticking out of the fretboard and expose their sharp edges and burrs. But if both the fret crowns and the tangs extend to the very edge of the fretboard due to this simple fretting method, there is inevitably zero margin for wood shrinkage*.
* "That's what she said"
Custom Shop Telecaster showing how the fret tangs reach to the fretboard edge
Better than beating you around the head with technical woodworking terms is showing you some scary pictures! Here's an example where "fret sprout" didn't even happen yet, the fret tangs were simply not properly filed all the way down to the (strangely rolled) fretboard edge:
Protruding fret tangs on a 2022 Telecaster (MIM)
Here's what happens when real fret sprout hits the finish on a maple neck:
Fret tangs pushing the finish off the wood after wood shrinkage (MIM Strat)
The Japanese "hidden tangs"
First off, I don't know where this method was really invented, and it wasn't used by Tokai only: Many if not most of the more ambitious Japanese factory guitars made in the second half of the 70s featured this kind of fretwork. Secondly you may think that they needed to do that due to the humid climate in Hamamatsu - but Hamamatsu and L.A. are both on the 34th parallel north and the relative humidity seems pretty comparable over the year:
Relative humidity in the Kanto region (blue) vs. SoCal (amber)
So what were they doing different? In one sentence, they were cutting the frets, particularly the tangs shorter than the fretboard width, then filled up the fret slots with putty, shellac or simply finish to "hide" the tangs:
Nicely rolled TE70 bass-side fretboard edge with filled fret slots
Alas I don't know how exactly that was done in the Shōwa era, either the frets were cut to precise length before inserting them (or even ordered pre-cut from Sanko), or the fretwire pieces were only undercut ("nipped" tangs) and the surplus crown material sanded down after insertion.
"Nipped" fret tang
Modern day factory images show a belt sander and a worker apparently creating the crown bevel:
Long belt sander in the Onchi-cho factory 2012
Here's an image trying to show why this is nice - the pic was taken straight from above even if it looks it was taken from an angle - it shows how the fret crown does not extend beyond the rolled fretboard shoulder, as if the neck was bound:
Why I wanted to show this is that they obviously went that extra mile to make sure that the necks feel good and fret sprout will never be a thing on these guitars, or at least not a big one (which is when the fret tangs are sticking out, a bit more of a PITA to fix).
Unlike the Ensenada-Fenders shown above, the nicely rolled edges are not disturbed by the fret ends having a different radius and extending a bit beyond the edge. The edges are really nicely rolled, for some reason a bit more intensively on the bass side than on the treble side on my guitar. They sure felt already "broken in" and comfy like typical vintage originals when the guitar was new and not a vintage guitar itself.
Fretboard edge rolled at a time when "rolled fretboard" wasn't really on everyone's lips yet
Since I've seen pretty varying degrees of edge rolling on Tokais, I assume that the amount was at the discretion of the worker doing this that day, just like in the old Fender Fullerton factory. This kind of treatments certainly came with a little bit of a time penalty and higher skill requirements, and it was applied to all guitars, not only the pricier ones:
Lower grade (simple tuners) Limited Edition guitar
Besides the nice feel - should fret sprout ever happen on those guitars, it's a matter of a few gentle kisses with a fret end file or a short visit at your tech guy to handle this!
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