Rickresource Rickenbacker Forum

Here's an odd one I've not seen before and cannot seem to correct.

The neck has a bit of a back bow wave, or hump, at about the 12th fret. So what I see when looking down the neck is dead flat from the 20th fret to the 12th, the slight hump between 12 and 10, then a slight bow between 10th and 1st frets.

Tightening the truss rods results in too much bow and too high an action. Loosening the truss rods results in nothing because they're already completely loose. Taking the strings off results in an expected perfect back bow without the wave at the 12th fret.

I'm using relatively light strings (.035 through .110, 5 strings) and would really rather not go to a higher gauge. I have tried that and they just flat out feel too darn tight for my liking. I've used these exact gauge strings with no issues (except 4 strings) on another 4003 with no issues.

Any thoughts on what I'm seeing? It's not impeding play terribly, but is annoying in that I have to raise the bridge more than I'd like to to get away from that hump at the 12th fret.

That neck has always had that anamoly. Jeff adjusted it and had the action real low on it. He may have a tip or two. I raised the action so it had no effect for me.

You're telling me you raised the action! I don't want you to think I was dissatisfied at all. Quite the contrary. I'm just the opposite end of the spectrum from you on action likes and got horribly spoiled by my last 4003. Perhaps I need to toughen up and go a little higher and thicker strings.

Jeff likes it REALLY low so I know it can get there! I'm kind of a hack and play hard. The low action just makes everything buzz and clack...

Since the neck has back bow in it, putting heavier gauge strings on it would only help. .035-.110 sounds kinda gutless for a 5-string. The stock strings on a 4003S/5 were .045-.115. Another good choice would be D'Addario rounds at .045-.125.

No, the gauge I use is not gutless. They've worked very well for many years for me with plenty of cajones to the sound. The full neck back bow was only when strings are removed, as I would expect. With tension on, the hump still remains at the 12th fret. Heavier strings have only resulted in having to go to a higher action below the 12th fret than I prefer to get over that hump.

I would take the truss rod nuts off and push the rods until the pickup ends are out of the wood and see if you can rotate them freely or if they bind because of being curved. I just found one rod on my 4003S slightly curved and I rotated it 180 degrees and got rid of a small hump around the 3rd fret. See the thread titled "What are the tricks to get a 4003 neck straight??" for examples of extensive curving and the results of straightening the rods.

I just saw your other post in that thread and it sounds like yours are curved, but check them.

Dale Fortune has posted about using a narrower rod to drive the truss rod out with tapping gently. If you are afraid of popping the fretboard, use a clamp with something to protect the wood both sides to hold it together.

I am waiting for one child to wake up and the other to finish school for the day and head to the hardware store for just such a rod as you describe for tapping the truss rod out. Glad to know I'm on the right track. Thanks for the tip about using a clamp as well.

There appears to be masking tape in there holding things up a bit. I've read in here about doing that to dampen rattle inside the neck. Is that a factory procedure to use tape or shrink wrap or is it likely this has been done before on this bass?

I apologize for any duplication with the other thread now running on this. I thought I had something odd and it turns out the info in that thread is helpful in this.

Hey, that's what this place is for! They put masking tape between the rods to hold down vibration. I think JH has mentioned heat shrink as a suitable replacement.

You put a voodoo hex on my neck, didn't you, Charly?

Again, it's not such a bad issue. Just trying to wring out the last little piece of making her mine all mine the way I like it: low and loose.

That didn't quite come out right.

Jeff saw it way before me, must've been him! It went from the seller to him sight unseen for a 4-2-5!

O.k....here's what I have found:



To clarify and lessen my paranoia of killing my baby, have I correctly read in the other thread that these can be straightened and I may be looking at a successful fix to a neck problem? I did find this line in that thread from Mark:

"After you pull the rods put a 24" straight edge on your neck(strings off of course) and make sure an upbow hasn't developed in the neck wood, this would definitely work against the rods."

When we're saying upbow, we're saying the opposite of relief, correct? If so, then I do, indeed, have about 1/8" of upbow from the 12th through 20th fret. None is apparent between frets 1 and 12. Am I still good to go with straight rods?

Thank you all for your patience and advice.

I think at this point I would hope for Paul or Dale to comment. This may need a steam/clamp job, but I'm guessing.

For clarification, are you saying the neck does this at the 12th on up

______________/------\

or this?

--------------\_____/

Kind of like this:



Head is to the left, body to the right of the image, the lift at the right is the 12th fret. Straight from 12-20, usual slight relief between 1 and 12. Loosening the truss rod nuts all the way results in lower relief closer to straight (but not dead straight), except for now hitting the wave. Raising the bridge to get over the wave defeats the lack of relief in the lower frets.

The drawing is cruddy and overly dramatic, but it gets the point.

I remember that bass ... I seem to remember that the neck was flat from the 3rd to 14th frets ... from fret 2 to the nut it curved up ... and from fret 14 to 20 curved down ... it is a one of a kind Ric ... I have owned a lot of Rics and worked on a lot more and I have never seen a Ric quite like that one ...

But adjusted right that neck plays quite nice ... the only problem is if you like to play a high C, or high D ... the action was a little high that far up the neck ... but from the 1st to 12th frets it was a sweet player ...

you will want to learn how to adjust your rods ...