4001 Truss Rod Help

[deblase4001]

Greg,

I then bent a curve in the rods so that when I placed the ends of the rods on the desk the apex/middle was about 2 to 2.5 inches above the desk. They were actually quite easy to put back in the slots despite the curve in them but I would strongly advise clamping the end of the fretboard securely because the bent rods may exert an upwards force on it as you push them in and you don't want to pop it off.

Good luck!

Good to know - I was worried about reinserting them with the bend. Did you just bend the rods by hand or use something else?

[bassduke49]

Also check out Ted Staberow's "Anatomy" series (which will be incorporated into my book):

viewtopic.php?f=2&t=387829

[Kopfjaeger]

Thanks, so my archers "bow" analogy was fairly correct. I have a much better understanding now. As long as the plate on the nut end is making contact with the non threaded end it will cause the rod to back bow and counter act the string tension.

That seems like a bit of pressure on backside the fretboard as the rod is counter acting the string tension.

This all has been very insightful since like I've said before, I find it's better for me to visualize how something works in order to understand it better.

Awesome attachment Paul! Thanks. When armed with this and Joey's videos this is much clearer.

Sepp

[cjj]

So new style truss rods merely sandwich the neck between the adjustment plate and the acorn nut? It's that tension that "hopefully" keeps the neck straight while under load?

The new truss rods sit in a curved channel in the neck so that when you put tension on them, they bow the neck to counteract the tension of the strings...

[antonius]

Greg,

I then bent a curve in the rods so that when I placed the ends of the rods on the desk the apex/middle was about 2 to 2.5 inches above the desk. They were actually quite easy to put back in the slots despite the curve in them but I would strongly advise clamping the end of the fretboard securely because the bent rods may exert an upwards force on it as you push them in and you don't want to pop it off.

Good luck!

Good to know - I was worried about reinserting them with the bend. Did you just bend the rods by hand or use something else?

I bent the rods by hand. If you hold the rod horizontally with the threaded/longer length facing you, grip the fingers of both hands around the rod with thumbs outstreched and meeting in the middle, your cover about 12 inches and so can exert a good amount of controllable force on the rod at the point where your thumbs meet (and my hands aren't particularly strong). I just put a little bit of bend at one point, moved along an inch or two, did the same, and kept on going backwards and forwards along the length of the rod until there was a nice smooth even bow. Just a very gradual process with only a tiny bit of bending at a time to ensure I didn't overbend any particular area or put anything resembling a kink in it. As I worked I kept comparing the two rods to make sure they both had the same amount of bowing.

As you inevitably lose some of the the bowing and therefore some of the strength you've just put into them as you insert the rods I figured that it is better to bow more; put more strength in them than you need because you will lose some of it. It looks quite extreme when you see how much of a curve you've put into them, but in my experience it was worth it - and they did slide back in fairly easily. I guess each instrument is different, and I can't say for sure if this is safe for anyone else's bass, but this worked out well for me. I'm sure others will step in with cautionary notes if necessary.

[deblase4001]

Truss rods ready to reinstall. Hopefully this will do the trick. I straightened the threaded ends the best I could with a vise and pliers then bent a 2" arc in the rods by hand. I hope to have time to put it all back together this evening.

[Kopfjaeger]

Nice, the bend looks radical but like was mentioned, you'll lose a bit of it inserting it. Are you going the electrical tape route or shrink tube? Which segment gets taped or shrink tubed??

Sepp

[deblase4001]

There is a strip of electrical tape on the top and bottom part of the rod where they fold together. The existing tape still looks good, is intact, and still really sticky after 36 years I plan on leaving it on and just cleaning the rods up a little - they look pretty good.

[johnallg]

Nice, the bend looks radical but like was mentioned, you'll lose a bit of it inserting it. Are you going the electrical tape route or shrink tube? Which segment gets taped or shrink tubed??

Sepp

On the folded rods they have electrical tape between the rods but not encasing them because they need to flex and oppose each other to work as designed.

When you tighten the rod, it draws both ends towards the headstock. The angled shorter rod end hits the aluminum block and is stopped. More tightening will cause the rods to bow away from each other and "fill" the slot they are in, holding the neck in place. More tightening will bow the rods more, not moving the neck at all, but with enough bow (overtightening) the rods push out hard enough that the end of the neck will separate from the neck wood, as CJJ showed his bass had sometime in it's past ownership. But as a method of holding the neck where you want it (where you move it to and hold there while tightening) it works very well. My 4001 does not move with season and humidity changes.

[deblase4001]

Very happy to report that it worked The rods went back in easily and I was able to setup the bass just the way I like it. There is even room for more adjustment. The rods are working the way they should. Thanks again for all the help.

[kiramdear]

Greg, congratulations! My hat's off to you; it's not rocket science but it's a task not for the faint-hearted either. Looks like a perfect job.

And dontcha love this outfit?

[T.A.R.]

That's great to hear Greg! As Kira said not for the faint of heart.

[antonius]

That's great news Greg! I'm so pleased it worked. As others have mentioned, the 4001 rods do a great job once you understand just how they work and how to maintain them.

[jps]

I've done it, too, on a couple of Ricks. Great to hear you got it sorted out.

[rickenbrother]

Great job, Greg. Glad you got your 4001 setup well!