Fly Classic Neck Relief

[lemmy999]

I have a Fly Classic that I purchased new in 1996. Except when I hand carried it in the case from my first house to my second house, this guitar has never been outside my house, has never been exposed to humidity or temperature extremes, has always been in the case or on a stand, and has never been dropped. I have always used the same size strings that were installed at the factory (0.09 - 0.042) and I had never adjusted the truss rod or bridge height before. However I do have the bridged locked down.

Yesterday I checked the relief using multiple methods:

1. Using a digital action gauge on the 8th fret while depressing the low E at the 1st fret and the fret at the body indicated 0.019"
2. Using a straight edge and feeler gauges I got 0.019"
3. I depressed the low E on the 1st and 12th fret and measured at the 5th fret with the digital action gauge and got 0.012" (I've read on this forum that it was factory set to 0.007")

I have read several places that the trust rod on these rarely need adjusting and that a small adjustment makes a big difference (" one sixth turn yield a lot of movement"). So I'm wondering if it is typical to see this much change in a Fly? Also it took a full turn or maybe more to correct this. I now have 0.0075" at the 5th when fretting the 1st and 12th and 0.009 at the 8th when fretting the 1st and body fret. At this point my action was 0.060" and 0.048" (bass E/treble E at the 12th) so I adjusted the bridge to get to 0.066" and 0.52".

It definitely plays much better now, but I'm still curious if having to make a full turn or more of adjustment is typical for a Fly that has never been exposed to harsh conditions. Thanks.

[mmmguitar]

I'm still curious if having to make a full turn or more of adjustment is typical for a Fly that has never been exposed to harsh conditions. Thanks.

I would say so. If the neck was previously straight without the truss needing to exert any force of its own, the truss rod (piano wire, in your case) would need to be tightened until it was under tension sufficient to begin affecting the neck. Fly and Nitefly necks can have this "issue" where the CF is doing more to keep the neck straight than the truss is; and it can result in surprisingly large adjustments being made once seasonal changes in relief have become noticeable.

I previously lived in a region which seasonally had temperature swings of up to fifty degrees (Fahrenheit). Of the guitars I had, the only ones which didn't require truss adjustments were the Vigiers (which have CF blocks instead of truss rods). The all carbon-graphite Steinberger necks required maybe a quarter turn adjustment, the Parker Flys required as much as a half turn, the CF-reinforced 5-ply Strandberg necks required two days or so to really dial in, and my "normal" wood guitar necks (single or multi-ply with two-way trusses) would similarly require a few days to really dial in for the new season.

I had to make these adjustments a few times per year. That the first batch of '93 Flys had too much CF reinforcement for the truss to really affect relief means that the truss design of the Fly is moreso there to allow you to dial relief in to your preference (which your measurements are handy for) than for the sake of stability. That said, the depth that the Fly nut slots were cut to on each one I've owned seems to be for the sake of a notched straight edge showing the neck to be as straight as the truss can make it, and at the point where any further tightening of the rod will begin to cause buzzing in the first few frets, having been the ideal setup being strived for. Over the years, I've found that dialing the truss tension in to that point results in less adjustment being necessary to dial the relief back in the next time the elements wreck their havoc on my guitars.