How to fix a Fender truss rod
V-6214
This job used to be so hard that guitar necks got thrown away as "unfixable." Dan Erlewine shows that it's now pretty simple with StewMac Truss Rod Rescue Tools.
Video Transcription
[on-screen text reads: StewMac tools + ideas for guitarmaking. How To Fix A Fender Truss Rod]
Dan Erlewine: Here's a 1962 Stratocaster neck. It's a real beauty, except it has a broken truss rod. If you look down in the truss rod adjusting hole, you'll see a wood at the bottom and a little bit of metal poking through. It's just broken clean off. I'd even say they used an awfully big screwdriver to get down in there. Look how it marred it. It used to be that when this happened, you'd throw the neck away because it was so hard to fix it. You'd have to pull off the fret board, take out the truss rod, make a truss rod, unless you could get one, and put it all back together in, and it was just impossible for most people to do that. And it's not always a broken rod that you're going to deal with, more often it's a rod that's kind of mashed and you can't get a nut either off of it or on it. Come in and have a look.
How to fix marred threads
Here's a real good example of marred threads. If I spin it around like that, you can see the flats on them. It's hard to get a nut on it. It gets on about that far, and then it binds up. The fix for that is the cutting die [on-screen text reads: Thread Cutting Die - stewmac.com]. This is a 10/32 die hardened steel, and it's chamfered on the way in. Slight bevel, so it can fit onto a rough thread. And once I get it started, I'm going to switch to driving it with this Allen wrench. Now it's cleaning them up. This is called chasing. And I'll thread a bit and back off, thread a bit and back off. You want to clear those chips. Voila, just like that.
How to fix a broken truss rod
Or let's say this is a broken truss rod, and you have to add threads to it. Put a little Vaseline on there to lubricate it a bit. This time we're going to start cutting some new threads.
It takes a little elbow grease to be sure, and you'll have to take the die off and clean it a couple times to get that cut metal out of there. There we go.
How to rescue a recessed truss rod
Now let's go back and look at that strat. So you saw the end of the rod down at the bottom of that hole, but it's surrounded by wood. If we can take the wood away, we'll get at the fresh threads that are still there. So I'm going to get that maple out of there with the relief cutter [on-screen text reads: Relief Cutter For Fender - stewmac.com]. It's got four really sharp teeth. It's a boring tool, and a hole through the center that slips right over the rod and doesn't hurt the threads. That'll chew that maple out of there in a second. So I'm going to rescue this poor thing. And this cutter has a hole for an 8/32 rod. I love this sound.
I think I've cut as deep as I need to go. I've done it quite a few times. I can measure that [on-screen text reads: Luthier's Digital Caliper - stewmac.com], and there's the original nut that would come on a fender. It's much shorter. It's too short to work here. So what we have is an extension nut that will end up right where it should be at the end of the neck and have a good grip on the threads. And what I want to do is cut a little bit deeper so that I can put a metal spacer in there for the truss rod nut to bear against when you tighten it, instead of just wood. What I'm going to do now is put some Vaseline on the inside of the threads on the nut, lubricate it a bit so it works smoothly on the threads that have been buried in there for years.
And see what we got. It's too bad they marred that hole and make it look so big, but that was done before it came into this shop. Now I'm sticking out just a little bit, but I'm guessing when I tighten this, I'll be right where I want. Just snug. That's good. One fixed truss rod.
Fix a Fender bullet truss rod using a rethreading pilot
For the Fender bullet truss rod, which adjusts at the nut end of the guitar, we have a different fix because we have a slope of wood that's hard to cut into, and this hole is smaller than other Fenders, and it's smaller than the cutter. To try to get in there, you could cut all over the edge of it and mangle it. What we have is a Truss Rod Rethreading Pilot. It's made out of brass. It's small enough to slide into the hole from the factory over the truss rod when you get down in there, and it accepts the pilot and keeps it on center, and the cutter just follows it right down in. So we have rescue tools for all the Fenders and for Gibson too with their 10/32 thread, and other guitars that use that kind of a rod.
