Bi-Flex Truss Rod Issues (2004 American Deluxe Strat 50th Anniversary)

Discussion in 'Tech-Talk' started by LeonardMcCoy, Dec 18, 2018.

  1. LeonardMcCoy

    LeonardMcCoy Strat-Talk Member

    Messages:
    42
    Joined:
    Dec 18, 2018
    Location:
    UK
    Recently, I purchased a preowned 2004 Fender American Stratocaster Deluxe 50th Anniversary (Left handed) off eBay.

    s-l1600.jpg s-l1600 (1).jpg 7.jpg

    The neck shows an up-bow. There is a relief of at least .015" at the 7th fret at the bass-side E string when doing a Fender relief check (the 1st and 17th fret being pressed down).

    Following is the issue when adjusting the neck:
    1. The truss rod nut is at least as worn as the original 1/8" Fender allen key it came with. Loosening the truss rod is no problem but tightening it is. When attemping the latter, the allen key will simply slip off.
    2. The truss rod itself seems to be very tight already and can't be further tightened especially with the nut being as worn as it is.
    I have been told by a luthier and a guitar technician to either return the instrument (in progress) or get a new custom-made neck by Warmoth, the latter of which presenting other difficulties (lefty 50th anniversary) and inconveniences.

    I have heard there also to be the option to surgically replace the nut adding a few washers in the process to potentially allow for further tightening of the truss rod. What are your experiences with this method, and how would you assess its rate of success considering my case here?

    I would like the neck to be almost perfectly straight for a proper fretjob and setup, with the bridge being flush with the body. I want to get to at least a Fender spec-level of relief (.008"-.010").
     
  2. henderman

    henderman Most Honored Senior Member

    Messages:
    9,443
    Joined:
    Dec 4, 2013
    Location:
    largo,fl
    a normal one way truss rod can sometimes be fixed by adding a washer or 2 but a bi-flex truss rod is an entirely different animal.

    it works in both directions so the nut is going to be able to be turned in both directions. the washer thing is not a solution.

    i would return it since it can not operate as needed.
     
    problem-child and Believer7713 like this.
  3. fmmlp

    fmmlp Strat-Talk Member

    Age:
    47
    Messages:
    56
    Joined:
    Jun 4, 2018
    Location:
    ar
    If it's possible to remove the nut to put washers, then is possible to replace it, or make a slot or solder a stub to adjust it without slipping .
     
  4. LeonardMcCoy

    LeonardMcCoy Strat-Talk Member

    Messages:
    42
    Joined:
    Dec 18, 2018
    Location:
    UK
    What I forgot to mention was that the guitar originally came with lighter strings. At least .009s compared to the .010s I later set her up with.

    A backbow is of no concern with this guitar, likely never will be. I need to adjust the truss rod in one way only (righty-tighty) to fight the up-bow.

    I guess what I'm really asking is impossible to answer because no-one really knows, worn nut issues aside, whether or not the truss rod is maxed out. I'm fairly confident the nut surgery can be done without too much of a hassle but whether that will solve the up-bow in the neck I don't know.

    The eBay dispute to return the instrument will be decided within the next 48 hours.

    For any insights or comments I'm grateful.
     
  5. B. Howard

    B. Howard Strat-Talker

    Messages:
    152
    Joined:
    Jun 7, 2013
    Location:
    Magnolia DE
    The plug can be pulled , the truss nut replaced and then the plug glued back in. A bit of finish touch up and good as new. I make this repair at least once a year for someone.... Much cheaper than a new neck.

    This caused because people treat these like a true 2 way rod when adjusting and they won't work like that. You must flex the neck manually as you adjust. You move the neck and the rod keeps it.....
     
    rocknrollrich likes this.
  6. LeonardMcCoy

    LeonardMcCoy Strat-Talk Member

    Messages:
    42
    Joined:
    Dec 18, 2018
    Location:
    UK
    Do you insert additional washers as well? Does it make sense to do so?
     
  7. henderman

    henderman Most Honored Senior Member

    Messages:
    9,443
    Joined:
    Dec 4, 2013
    Location:
    largo,fl
    the washer trick is for 1 way truss rods and will not fix your issue with a bi-flex rod same as i posted before, they are entirely different and do not work the same way.
     
    Guy Named Sue likes this.
  8. LeonardMcCoy

    LeonardMcCoy Strat-Talk Member

    Messages:
    42
    Joined:
    Dec 18, 2018
    Location:
    UK
    Can you elaborate? There is no need to retain the bi-flex function.

    The bi-flex truss rod is threaded so additional washers should prevent the nut from running out prematurely when tightening the truss rod to fight the up-bow in the neck.

    It's not unlikely that if I switch back to .009 strings, additional washers won't even be necessary especially when flexing the neck into the right position in advance.
     
    Last edited: Dec 19, 2018
  9. B. Howard

    B. Howard Strat-Talker

    Messages:
    152
    Joined:
    Jun 7, 2013
    Location:
    Magnolia DE
    No washers other than the one that is supposed to be there. Here is a pic of what is inside...[​IMG]
     
  10. LeonardMcCoy

    LeonardMcCoy Strat-Talk Member

    Messages:
    42
    Joined:
    Dec 18, 2018
    Location:
    UK
    Here's a funny little story that came to me at 3am. Now, you may think that it might have been obvious from the beginning. But three local professional guitar builders who have seen plenty of guitars and repair scenarios in their life didn't think of it at all. And me neither until now.

    In November 2008, strayedstrater posted a synopsis on the various rare issues with Fender's Bi-Flex truss rod and how to address them properly. I will quote it here in full for posterity's sake (because it is that good) and mark only the part relevant to my case here in bold type:

    Fender truss rods are somewhat prone to running out of adjustment range. The adjuster nut bears directly on a narrow ring of wood surrounding the truss rod, and the wood sometimes compresses. It's not "common" or "frequent", but every tech has run across bottomed-out Fender rods. It's easy to fix that on a regular Fender rod -- unscrew the adjuster until it falls off the rod, add a couple of washers and reinstall the adjuster. The same repair works on a Bi-Flex, but the adjuster is held captive by the walnut tube so you need to drill it out (and then glue in a new one if you want to retain the Bi-Flex function -- but if you bottomed out the rod you probably won't ever need to use the Bi-Flex function). BTW, this problem is way more common on heel-adjust Fenders than head adjust Fenders (Bi-Flex, Bullet adjuster, or MIM style).

    But that's covered by the lifetime warranty on any new Fender. They generally just replace a Bi-Flex neck with a new one.

    A semi-common problem with Bi-Flex rods is adjusters that appear to have stripped sockets, but really don't. The sockets are flared -- larger at the open end -- to make it easier to get the wrench into the socket down inside a blind hole. The sockets are installed before the walnut tube is glued in, and then the neck gets sanded, spray painted, and buffed with polishing compound. The socket can get partially plugged with residue, down at the tight fitting end. So when you stick a wrench in it, it doesn't seat fully and spins in the flared part of the socket. Poke a straightened paper clip or small screwdriver into the socket, dig it around, then tilt the neck so the debris can fall out. (While it seems like it would be freakishly rare and something the assembly line workers would notice, this is by far the most common problem with Bi-Flex truss rods -- that doesn't mean it happens a lot, it means the other problems are really, really rare.)

    Sockets can actually strip of course. You can take the next size bigger wrench and file it down to fit the socket. Or you can just shove a large Torx screwdriver into the socket and let it bite into the walls of the socket. When adjusting the neck with a compromised adjuster, you should "help" the rod by pulling the neck into position and then adjust the rod while there's no tension against the adjuster. (Don't use the rod to pull the neck straight -- manually pull it, then adjust the rod to hold the neck where you pulled it; just like adjusting a pre-'80s Ric.)

    Or drill out the plug, unscrew the socket (there are ways to do that even if the socket is completely rounded out), screw in a new socket, glue in a new walnut tube and spot refinish. (The walnut tube and spot refinish are optional if you don't need the Bi-Flex feature -- just shove in a black plastic tube like a MIM or leave it bare.) Definitely a PITA (I won't own a Bi-Flex -- I've never needed to add more relief to a neck so I don't feel the need for the Bi-Flex function; I consider them a needless complication) but it's fixable.

    "I bought a brand new American Series Limited Edition Strat a few years ago only to later find out that the truss rod nut was entirely stripped !!! ... This guitar is now useless."

    They denied your warranty claim on that? Why?

    If you bought it from a non-authorized dealer, it's not Fender's problem if "some "music store dude" ... did it in an attemt to adjust the neck relief." It's the non-authorized dealer's responsibility.

    Regardless, it's fixable. It can be worked around without repair by using a modified wrench or a Torx driver. Or it can be fixed just as good as new for about the price of a good setup.

    I don't mean to sound unsympathetic. That really sucks that you've been so unlucky. But these aren't common problems -- they only affect a couple percent of Strats (probably not that many). Fender introduced the Bi-Flex over 20 years ago and they've literally sold millions of them that never had any problems. The heel-adjust rod on the first couple of years of the Geddy Lee Jazz Bass needed more warranty repairs than all the Bi-Flex models over two decades put together. (A ton of the early Geddy Lee's needed washers -- I suspect that was caused by some problem in rod length or the front anchor rather than wood compression because it afflicted so many so quickly; typically it takes many years or decades for a rod to run out of adjustment.)

    So that's what I did then. I armed myself with a flashlight to light the dark of the socket and discovered layers upon layers of dust and residue. The previous owner probably didn't care about adjusting the neck or was using such light strings that there was simply no need to.

    Some cleaning with Q-tips did away with all the stuff in there. It's no wonder an allen key couldn't get a solid grip on. And the allen key the guitar came with wasn't that worn to begin with but I ordered a brand-new one just to be sure. What's best is that the lower layers of the nut are completely untouched, with only the upper layer displaying some small chip-outs due to improper use of tools.

    With the pre-bending method to create somewhat of a backbow first, as suggested above, it is now no problem to further tighten the truss rod. I think I can now make .010s work on this with only the slightest bit of relief (say .004") just like on my Gibsons and without forcing anything. With no strings on the neck is now dead-straight.

    As a side-note, adding additional washers on top of the washer that is already there might be pointless, as was discussed before. The truss rod nut already sits very firmly against the walnut plug. I'm not sure doubling the washer size there brings the desired effect. And adding washers someplace else (e.g., where the winding is) may make no sense.
     
    Last edited: Dec 21, 2018
    Andrew Wasson and maqcatt like this.
  11. LeonardMcCoy

    LeonardMcCoy Strat-Talk Member

    Messages:
    42
    Joined:
    Dec 18, 2018
    Location:
    UK
    Suffice it to say, with a brand-new Fender 1/8" allen wrench, I can get the neck perfectly straight now even with .010"-gauge strings on.
     
  12. LeonardMcCoy

    LeonardMcCoy Strat-Talk Member

    Messages:
    42
    Joined:
    Dec 18, 2018
    Location:
    UK
    Well, she definitely needs some form of fret work since she tends to fret out in the higher registers upon bending. Unfortunately, she didn't come with a compound radius to begin with, and a mere fretjob won't be successful to weave in a compound radius because that would make the highest frets (15th fret and onwards) much too low.

    A refret is imminent with subsequent Plekking (medium jumbo frets, stainless steel). It's going to be expensive either way, I guess.
     
    Last edited: Jan 3, 2019
  13. maqcatt

    maqcatt Strat-O-Master

    Age:
    72
    Messages:
    726
    Joined:
    Sep 25, 2008
    Location:
    silverdale wa
    Yes.
    LeonardMcCoy knows what he's talking about.
    I'll add one thing:
    Bending the neck physically, like over your knee, when adjusting (in either direction) also makes it so you don't have to wait a day for the neck to settle in like so many people claim.

    Some advise you to do truss rod adjustments in small increments and wait hours or days in between.
    It's not necessary. Just put some pressure on it and get it done in one operation.

    S Mac