Neck angle on 4001 and string tension

[antonius]

I read with interest the thread on the c64 with the neck that had pitched forward somewhat, apparently due to the tension of the strings put on it and the structure of the neck/body area. I'm not wishing to revive that debate about the design of Rickenbacker instruments, but it did make me nervously look at my old bass and think about what stresses my strings may be putting on it, and how best to preserve it and keep it in good playing condition.

I'd never noticed or even considered it before but on closer inspection it seems that the neck on my 1975 4001 has angled/pitched forward slightly. I'm not talking about the bowing forward of the neck due to relief but an apparent slight pivot at the neck/body intersection. I don't know if this happened years ago (previous owners had not taken good care of this bass, necessitating me getting the truss rods repaired and getting the fretboard levelled due to warping) or if it is more recent, or likely to progress further. Is this quite normal for a 38 year old 4001 or is is something I ought to be concerned about? How are the necks on your old 4001 basses? Have they pitched forward at all? I'm assuming they were built with no neck angle?

This slight pitching forward of the neck is not causing a problem on my 4001 and I'm able to get a good setup with decent action and it sounds and plays well, but I wouldn't want it to get any worse. I don't know if it is stable or likely to progress. So I'm having a re-think about the strings I use. I currently have D'Addario EXL170BT (45-60-80-107). The stated tension is 162.9 pounds. I guess I can deduct a few pounds from that due to the slightly shorter scale length of a Rickenbacker. That's not particularly high tension compared to the strings many people use but certainly higher than the approximately 145 pounds tension of Rickenbacker strings, which are presumably considered safe for a 4001. I know many 4001 basses can handle higher tension strings but I'm just wondering if I ought to play it safe and go down to slightly lower tension strings. Your thoughts?

[cassius987]

My '76 (also an abused bass) had this with a very minor "fall away" in the upper register so while doing other work to it because it was far from mint I opted to have the tailpiece countersunk 1-2 mm, which made a huge difference that more than corrected the fall away.

[Colonel Sanders]

How are the necks on your old 4001 basses? Have they pitched forward at all? I'm assuming they were built with no neck angle?

In my modest collection, the only 4001 neck that pitched forward is my 1968. The 3 piece neck from 72 to the end of the 4001 era was pretty sturdy. The only drawback being the uncoventional truss rod system. But is it really a drawback? Once you know how to use it, it is pretty good as it never needs to be adjusted until you change for strings with a different tension.

[rictified]

I think most basses will temporarily pitch forward under string tension as long as it is exerted, I know my 79 4001 will pitch forward a little depending on how much tension the strings exert on the neck. It goes back when I loosen the strings and causes no permanent problems at least on any basses I have ever had. If I change string gauges or to a different tension string I will take that into account and set it up over a period of several days to allow the neck to come to a new equlibrium. I don't worry about it unless it is excessive and cannot be compensated for by lowering the bridge within reason. If the bridge is riding the body, well you know. I tend to find a string I like and stick with them.

[cassius987]

I think most basses will temporarily pitch forward under string tension as long as it is exerted, I know my 79 4001 will pitch forward a little depending on how much tension the strings exert on the neck. It goes back when I loosen the strings and causes no permanent problems at least on any basses I have ever had. If I change string gauges or to a different tension string I will take that into account and set it up over a period of several days to allow the neck to come to a new equlibrium. I don't worry about it unless it is excessive and cannot be compensated for by lowering the bridge within reason. If the bridge is riding the body, well you know. I tend to find a string I like and stick with them.

You are talking about relief, which is a well documented phenomenon, but antonius is referring to the angle of the neck/body joint which can impact upper register action very dramatically even when the neck is dead straight under string tension.

[rictified]

I think most basses will temporarily pitch forward under string tension as long as it is exerted, I know my 79 4001 will pitch forward a little depending on how much tension the strings exert on the neck. It goes back when I loosen the strings and causes no permanent problems at least on any basses I have ever had. If I change string gauges or to a different tension string I will take that into account and set it up over a period of several days to allow the neck to come to a new equlibrium. I don't worry about it unless it is excessive and cannot be compensated for by lowering the bridge within reason. If the bridge is riding the body, well you know. I tend to find a string I like and stick with them.

You are talking about relief, which is a well documented phenomenon, but antonius is referring to the angle of the neck/body joint which can impact upper register action very dramatically even when the neck is dead straight under string tension.

I didn't read the whole post obviously but I saw that happen on 65 Fender Jazz, the neck was given additional stabilty by the body underneath at the intersection of the two and I guess instead of the whole neck slightly bowing it bent at the point where it left the body. I've never seen that happen on a Rickenbacker or at least to the point where it wouldn't straighten out when the stress was off..

[heinpete]

... the neck/body angle with bolt on necks can be adjusted by shimming, which is impossible for a neck through 4001. I also had an early 80ies 4003 which also had an angle of the neck towards the body. Hence the lowest bridge position was just the maximum of adjustment to have a comfortable low string height.

[cassius987]

The only fixes I know for this on a neck-through model are to countersink the bridge/tailpiece or to plug the pickup cavity and re-rout it much more conservatively, as Dane Wilder does. But he usually does it preventively for basses that will undergo high string tension. I don't think that method has been tried to actually repair a bad angle.

Neck-through construction definitely changes the tone of an instrument in cool ways (although I think it's wrong to say it increases sustain). I hear a lot more "harmonic richness" with neck-through instruments. The method does have its downsides, however, and this is possibly the biggest one.

[wim]

The neck of my '74 pitches forward too, as I said in that other thread.
There's nothing wrong with the rods, they hold up well.
What also happens is the bass detunes sharp when tilted backward and flat when tilted forward.
It has to be played in a vertical plane as much as possible.
This could be caused by the numerous refinishing (the neck is much thinner than average for '74 basses)
I have not noticed this on other 4001/3's

[antonius]

Thanks for the input guys, it's appreciated as always . As I said, it isn't causing a problem right now (the action at the 20th fret is only fractionally higher than at the 12th fret and I've still got room to lower the bridge a bit if I needed to), but I just wouldn't want it to get to the stage where it does cause problems. I think I might try some slightly lighter strings and see how the neck settles in with less tension. This is my only Rickenbacker and I couldn't afford another one so minimizing risk is probably the smart move...

[antonius]

What also happens is the bass detunes sharp when tilted backward and flat when tilted forward.
It has to be played in a vertical plane as much as possible.

My '75 4001 does that to some small degree, despite the neck feeling pretty solid. I think that's quite common, but obviously more evident the thinner the neck is. As you'll know yourself, you just have to be aware of the positioning when tuning and especially when setting intonation...

[antonius]

Update, for the sake of clarity

I've been having another good look at my '75 4001 and I'm now not so sure that the neck has pitched forward, or if it has, only very slightly. I had initially made the diagnosis based on sighting along the upper edge of the body/horn and neck, and it did look like the neck angled up immediately at the neck/body joint in relation to the body.

But when I sight along the lower edge of the body/horn and the lower side of the neck it doesn't look like the neck is pitched forward at all, (allowing for the slight rise due to some slight relief I like to have in my neck). This had me confused, but then when I placed the bass flat on a desk I noticed that the body wasn't completely flat, with the upper horn and opposite corner (where the output jack sockets are) making contact with the desk and rocking slightly on this axis. I then placed the edge of a long machinist's ruler from next to the tail-piece to the end of the upper horn and this showed that the body sloped downwards slightly on the upper horn. So it looks like the body itself, or perhaps just the upper horn, is slightly warped and this gives the illusion of the neck pitching forward when viewed from certain angles. So I might keep the current D'Addario EXL170BT strings on and just keep and eye on it, but it is probably fairly stable.

As mentioned above, a few years ago I had the fretboard levelled due to some S shape warping, and it now seems that the way previous owners 'looked after' this bass had also resulted in the body/horn warping slightly. It has only taken me 23 years to notice this....

[Ashgray]

The only fixes I know for this on a neck-through model are to countersink the bridge/tailpiece or to plug the pickup cavity and re-rout it much more conservatively, as Dane Wilder does. But he usually does it preventively for basses that will undergo high string tension. I don't think that method has been tried to actually repair a bad angle.

I'm about to find out if Dane's methodology will work to correct forward-pitched necks on my 1999 V63 and my 1982 4001FL, as I'll be asking my luthier to try this fix on both of them. The necks themselves are fine but there is a definite pitch forward at the body/neck junctions that I can only get around by setting the bridge heights at their lowest (so the height adjustment screws are not in use at all).

Ironically, my bass with the most tension on its neck, the 8-stringer, does not have this issue, neither does my 4002.

I'll update this thread once the work is done.

Ash

[Kopfjaeger]

Antony,

In a prior thread John Hall stated, "A current 4003 will indeed handle much more than that (145lbs) but this thread was addressing a 2005 model year 4001C64S which does not like tensions above 150 pounds. Of course, some pieces of wood will remain fine at much higher tensions."

Your 75 4001 has the neck pup at the 1 inch position, correct? If new 4003's come with 145 lb (approx) strings on them and the c64 v63's at the 1/2 inch position have difficulty at 150 and above, I'd try to keep your string tension closer to 140 just to be safe.

However, my 73 4001 wears .105, .079, .059, .043 and she is perfectly fine!! Once again, i think this bass is an anomaly!! Both my 4002's do not like heavy strings. My Walnut 4002 wears factory RIC gauge Curt Managan strings and recently I was taking a peek under the TRC and I noticed one truss rod end is pushed against the back wall of the cavity. Time to lighten up a little on that bass. My 77 4002, she wears .098, .073, .055, .039 and is happy as a clam.

My 1965 4001 has the opposite issue. She wants heavy strings and I'm not inclined to allow that to happen. Her neck has a back bow to her with zero tension that just barely straightens with a set of .098 strings. Barely any truss rod interaction. I'm willing to go to a set of .102 and hopefully exert a bit more truss rod action on her. I do not wish to stress the headstock or the neck joint with heavier.

Moral to this story, use the least tension strings that your particular instrument will handle with ease. Do not exceed 150 lbs. that's my recommendation.

Sepp

[antonius]

I hear you Joseph, and thanks for your advice. The only reason why I am reluctant to take off the D'Addario EXL170BT (45-60-80-107) strings is that I really like the feel and tone I get from them, and the 107 E string combats the tendency for note-choking fret buzz I sometimes got on frets 2-5 on the E string when playing 16th notes with a pick when using lower tension/smaller gauge E strings (putting a bit of relief in the neck helped a bit too). When playing with fingers I don't have any problems, but I like to play with a pick about 50% of the time. These strings are ok for occasional downtuning to DGCF too.

Yes my bass has the neck pickup at the 1" position, but the rout looks like it is bigger than it needs to be and it could almost accommodate the pickup at the 1/2" position.

As I said, I think my bass is probably stable, and the truss rods easily cope with the strings I am using, but at the back of my mind a voice is telling me to err on the side of caution, in light of what I've read about the potential weakness in the neck/body junction. I may look at getting some Rickenbacker strings as they still have a 105 E, whilst the thin A and D strings keep the overall tension right down. I've used them before and they are good strings, although they are 50% more expensive than the D'Addario set here in the UK. Or perhaps look at getting D'Addario singles at 45-55-75-105...