Truss Rod Adjustments

[Cthulow]

So, I have a new PRS Kestral 4-string that is a beautifully executed, neck-through bass and I'm blown away at the level of quality-control applied to this "entry-level" (does SE stand for something like "student edition"?) instrument. And, it sounds freakin' amazing with the TI Powerbass strings I've installed.
Here's the situation, however....it would appear that the truss rod is at the end of its adjustment - in other words, the relief on the neck can be decreased no further, since turning the adjusting nut/threaded sleeve starts to bind/meets resistance to further tightening, as if it has run out of threads at the end of the rod.
Anyway, I thought I had heard of a simple solution to this which was, adding a washer of sufficient thickness (or maybe two or three thinner ones?) so that a slightly further decrease in neck relief could be achieved without running out of threads on the truss rod end. In this case, it wouldn't take much of a reduction in neck relief to set up the instrument as I would like. Can someone comment on whether I can use this as a viable solution, if it is carefully implemented?
As an aside, I also have an Ibanez SR655, which has turned out to be a very satisfactory instrument, but which has TI Jazz Roundwounds installed, and I think they are a lower tension than the Powerbass strings on the PRS. That bass almost plays itself, with low action and it is almost unbelievable the way all of my adjustments have come together, making that instrument incredibly comfortable to play. You could say the action is almost too low, precluding more aggressive plucking (digging in), but that's not really an issue for me - I will just use that bass differently from the PRS Kestral...the Kestral will probably be set up with a little more relief and slightly higher action, allowing me to "dig in" more. But, I digress....again, does anyone here know whether adding a washer/washers at the end of the truss rod is something I can try out without causing damage (if implemented carefully)?
-thanks in advance for any advice/cautioning....gratefully, Cthulow

 

[96tbird]

If it’s new as your say, and it’s out of adjustment room…. Return it. That’s not acceptable.

 

[Zooberwerx]

So, I have a new PRS Kestral 4-string that is a beautifully executed, neck-through bass and I'm blown away at the level of quality-control applied to this "entry-level" (does SE stand for something like "student edition"?) instrument. And, it sounds freakin' amazing with the TI Powerbass strings I've installed.
Here's the situation, however....it would appear that the truss rod is at the end of its adjustment - in other words, the relief on the neck can be decreased no further, since turning the adjusting nut/threaded sleeve starts to bind/meets resistance to further tightening, as if it has run out of threads at the end of the rod.
Anyway, I thought I had heard of a simple solution to this which was, adding a washer of sufficient thickness (or maybe two or three thinner ones?) so that a slightly further decrease in neck relief could be achieved without running out of threads on the truss rod end. In this case, it wouldn't take much of a reduction in neck relief to set up the instrument as I would like. Can someone comment on whether I can use this as a viable solution, if it is carefully implemented?
As an aside, I also have an Ibanez SR655, which has turned out to be a very satisfactory instrument, but which has TI Jazz Roundwounds installed, and I think they are a lower tension than the Powerbass strings on the PRS. That bass almost plays itself, with low action and it is almost unbelievable the way all of my adjustments have come together, making that instrument incredibly comfortable to play. You could say the action is almost too low, precluding more aggressive plucking (digging in), but that's not really an issue for me - I will just use that bass differently from the PRS Kestral...the Kestral will probably be set up with a little more relief and slightly higher action, allowing me to "dig in" more. But, I digress....again, does anyone here know whether adding a washer/washers at the end of the truss rod is something I can try out without causing damage (if implemented carefully)?
-thanks in advance for any advice/cautioning....gratefully, Cthulow

How can I ignore anybody sporting a BOC avatar?!?

You may have a couple issues:

*Are you manually flexing the neck backwards while tightening the truss rod? This is paramount!

*How much relief do you currently have on-board?

As others have mentioned, I wouldn't dick around with it too much...return it if it can't be adjusted to spec. OTOH, if you really like the bass, consider installing a lower-tension (light gauge) set of hex core strings to maintain the desired stiffness.

Riis

 

[Cthulow]

I guess I did think the BOC “questioning cross”, purported to be related to Kronos (ancient name for a god representing the planet Saturn) might provoke a comment or two, but you are the first! It is also proudly displayed on my pu truck and I’ve seen them around 15 times, making me a bit of a CultHead, if you like.
Anyway, you didn’t specifically comment on the washer solution, so I’m still looking for a reply to that.
Yes, I always gently apply pressure to the neck (admittedly in a crude but careful fashion usually with the bass positioned such that I can push on the neck with my knee on the back of the neck when reducing relief or in the opposite direction when allowing the relief to increase slightly.
I also want to find out if the PRS basses and guitars use a so-called “dual action” truss rod. It looks like, if that is the case, all I need to do (if I understood this correctly) is: back off the adjusting nut until the neck straightens out more (less relief or actually flat), then go from there as a baseline (pun intended)?

 

[Cthulow]

If it’s new as your say, and it’s out of adjustment room…. Return it. That’s not acceptable.

Nice vintage “test pattern” from the 1950’s for your avatar! If you are interested, see my post below and also zooberwerx’s.

 

[Cthulow]

Ok, it looks like the Kestral bass does have a dual action truss rod, so I will have to take that into account when adjusting. Not familiar with how this works but need to familiarize with same.

 

[Zooberwerx]

I guess I did think the BOC “questioning cross”, purported to be related to Kronos (ancient name for a god representing the planet Saturn) might provoke a comment or two, but you are the first! It is also proudly displayed on my pu truck and I’ve seen them around 15 times, making me a bit of a CultHead, if you like.
Anyway, you didn’t specifically comment on the washer solution, so I’m still looking for a reply to that.
Yes, I always gently apply pressure to the neck (admittedly in a crude but careful fashion usually with the bass positioned such that I can push on the neck with my knee on the back of the neck when reducing relief or in the opposite direction when allowing the relief to increase slightly.
I also want to find out if the PRS basses and guitars use a so-called “dual action” truss rod. It looks like, if that is the case, all I need to do (if I understood this correctly) is: back off the adjusting nut until the neck straightens out more (less relief or actually flat), then go from there as a baseline (pun intended)?

TBH, I've never introduced washers at the headstock...always the heel...so I can't speak with any authority on the issue. It's a non-issue if a dual-acting rod. Assume the position when adjusting: bass clamped between knees, left hand clamped upper neck, left forearm pressed against back of neck:


Met the band but not the Bouchard Bros. My wife, Susan, is partly culpable for killing Allen Lanier. At 5' tall, she put him in a side-hug at a gig...about scared the life out of him. RIP.

Riis

 

[Dirk Diggler]

Washers are an old classic Ric fix, but it really doesn't solve your problem.

As already suggested you might need to help it into place, if it's a dual rod you will feel some resistance if you're tightening.

If you aren't comfortable with adjusting it, take it to a tech that can set it up correctly.

 

[Cthulow]

TBH, I've never introduced washers at the headstock...always the heel...so I can't speak with any authority on the issue. It's a non-issue if a dual-acting rod. Assume the position when adjusting: bass clamped between knees, left hand clamped upper neck, left forearm pressed against back of neck:
View attachment 4601904

Met the band but not the Bouchard Bros. My wife, Susan, is partly culpable for killing Allen Lanier. At 5' tall, she put him in a side-hug at a gig...about scared the life out of him. RIP.

Riis

Ok, tried doing the adjustment as you demonstrated...a little different than my way, but could be more effective/less risky! A lot of binding going on, like I just can't tighten it at all, but that doesn't seem right. Right now I've applied some Tri-Flow penetrating oil around the nut and will wait and see....first try carefully backing off the tension, then trying in both directions to see if the nut frees itself, as now it appears to be binding in both directions. Could they have locked it in (intentionally or inadvertently) at the factory with some kind of adhesive or whatever?

 

[Zooberwerx]

Ok, tried doing the adjustment as you demonstrated...a little different than my way, but could be more effective/less risky! A lot of binding going on, like I just can't tighten it at all, but that doesn't seem right. Right now I've applied some Tri-Flow penetrating oil around the nut and will wait and see....first try carefully backing off the tension, then trying in both directions to see if the nut frees itself, as now it appears to be binding in both directions. Could they have locked it in (intentionally or inadvertently) at the factory with some kind of adhesive or whatever?

The nut was adjustable to some extent and now doesn't move at all? Send it back...brand new means fully adjustable out-of-the-box.

Riis

 

[Cthulow]

Good advice. May have to look into getting some satisfaction (sending back?) to PRS. I've heard their customer support is exemplary. BTW, great BOC story before. A shame about Allen. Too bad you didn't meet the Bouchards. Both tremendously talented. Albert has been one of my all-time favorite drummers - how many rock drummers "swing" the way he did....so many songs where just his insertion of a press-roll or some other little "fillip" threw the song into overdrive! Joe also supremely talented....both of them composed some memorable BOC tunes!

 

[C Stone]

On a truss with the headstock access washers will usually work to get some further adjustability however the washers sold for this purpose are intended for heel access truss's and the washers diameter are too large to fit in the headstock cavity.

I have used split washers (lock washers) and flatened them with pliers, they generaly have a smaller outer diameter. Ace hardware has bins full of washers.

Not familiar with your bass just make sure it doesn't have a walnut plug over the truss nut.
If so I have a process for removing it to gain access but it does take a fair amount of work.

 

[Dirk Diggler]

Sounds like a dual action truss rod, it's working as expected.
It does generally require a bit of pressure to adjust them.

And no, companies don't usually use locktite or any adhesives on the truss rods.
It defeats the purpose of having an adjustable neck.

Have you tried clamping it down and manually moving the neck to where you want it?
Then it's just a matter to tightening it up to hold in place.

Wait a minute this is a PRS???? Unless you've done something bad, I'm very surprised there would be any actual rod issues, and yes send it back to the mothership.

Good luck.

 

[Cthulow]

Sounds like a dual action truss rod, it's working as expected.
It does generally require a bit of pressure to adjust them.

And no, companies don't usually use locktite or any adhesives on the truss rods.
It defeats the purpose of having an adjustable neck.

Have you tried clamping it down and manually moving the neck to where you want it?
Then it's just a matter to tightening it up to hold in place.

Wait a minute this is a PRS???? Unless you've done something bad, I'm very surprised there would be any actual rod issues, and yes send it back to the mothership.

Good luck.

Well, the amount of force I had to apply (whilst holding my breath anxiously) was quite a bit more than I would have expected. I carefully (yet forcefully) turned the nut a little both ways and over the last two days applied maybe a total of 1/2 cw turn (to decrease the amount of relief slightly) and now I am satisfied with the amount of relief I have. Do you, or anyone else reading this know whether this is typical of "neck-through" (not set-neck) instruments....in other words, a considerably stiffer trussrod/neck assembly that requires noticeably more force to adjust it?
Thanks any and all future posters for any info!
Cthulow, your obedient servant

 

[Dirk Diggler]

Absolutely, the key here is to get it where you want it.

Sure, neck through wants to stay straight.

As I said if you can help it into place, it should be less force needed.
If it's a relatively new bass, it might not have been adjusted since it's birth.
Woods certainly move, and dry winters can cause issues.

 

[Cthulow]

Thanks, Dirk, for confirming my uninformed suspicions - that a neck-through assembly will require a bit more force to alter its relief, especially, as you said, when those particular conditions exist - dry winter (I can see how that alone might make the wood itself stiffer....thinking of the exact opposite of that, namely steam-bending wood in a warm, wet condition....anyone ever consider anything as drastic as that to correct a stubborn neck bow?)...just kidding, I guess, but maybe there have been instances when somebody somewhere resorted to something a little more radical, such as this!

 

[Matt Liebenau]

Thanks, Dirk, for confirming my uninformed suspicions - that a neck-through assembly will require a bit more force to alter its relief, especially, as you said, when those particular conditions exist - dry winter (I can see how that alone might make the wood itself stiffer....thinking of the exact opposite of that, namely steam-bending wood in a warm, wet condition....anyone ever consider anything as drastic as that to correct a stubborn neck bow?)...just kidding, I guess, but maybe there have been instances when somebody somewhere resorted to something a little more radical, such as this!

Heat and bending can be used to straighten a neck. Steam would probably work but I’d keep it as a last resort. You’re probably going to ruin the finish and loosen a glued on fretboard and and other glue joints.

 

[Cthulow]

Heat and bending can be used to straighten a neck. Steam would probably work but I’d keep it as a last resort. You’re probably going to ruin the finish and loosen a glued on fretboard and and other glue joints.

You're absolutely right about ruining a finish and loosening glued joints. I was actually being a little facetious. Recently, though, in a somewhat related fashion, I found an acoustic/electric bass (Spector Timbre) that had been sitting around a local music store for the last 5 years, un-sold. I really liked it for a variety of reasons, but, when a technician at the store and I examined it on a workbench there, we noticed the bridge was peeling away from the top of the instrument (we imagined that maybe the store had it displayed in a sunny window where, over time, the glue under the bridge softened and string tension pulled the bridge away).
Anyway, after using an ordinary clothes iron and protecting the top of the guitar and bridge with a towel, I removed the bridge & re-glued it. My first attempt failed - didn't leave the joint clamped long enough. Then, the second time I left it clamped for almost 4 days and this time it stayed put. After this, however, a crack developed through the bridge, right through the bridge pins. Man, I'm getting off topic, eh?...well, some might find this interesting anyway, and I guess it is at least in the correct forum. So, the fix for the crack was to enlarge it slightly with my Dremel tool cutting blade, then fill the enlarged crack with epoxy. That sucker is now, I think, permanently immune to further cracking....I hope this was entertaining to you and others who may have stumbled upon this rant! Cthulow

 

[Matt Liebenau]

You're absolutely right about ruining a finish and loosening glued joints. I was actually being a little facetious. Recently, though, in a somewhat related fashion, I found an acoustic/electric bass (Spector Timbre) that had been sitting around a local music store for the last 5 years, un-sold. I really liked it for a variety of reasons, but, when a technician at the store and I examined it on a workbench there, we noticed the bridge was peeling away from the top of the instrument (we imagined that maybe the store had it displayed in a sunny window where, over time, the glue under the bridge softened and string tension pulled the bridge away).
Anyway, after using an ordinary clothes iron and protecting the top of the guitar and bridge with a towel, I removed the bridge & re-glued it. My first attempt failed - didn't leave the joint clamped long enough. Then, the second time I left it clamped for almost 4 days and this time it stayed put. After this, however, a crack developed through the bridge, right through the bridge pins. Man, I'm getting off topic, eh?...well, some might find this interesting anyway, and I guess it is at least in the correct forum. So, the fix for the crack was to enlarge it slightly with my Dremel tool cutting blade, then fill the enlarged crack with epoxy. That sucker is now, I think, permanently immune to further cracking....I hope this was entertaining to you and others who may have stumbled upon this rant! Cthulow

Heat and sun will loosen glue joints also. I’m pretty sure that quite a few of the inexpensive manufacturers don’t scrape the finish off of the top very well if at all before they glue down an acoustic bridge which will definitely cause issues down the road.

 

[lark_z]

You can certainly find posts re- "heat setting" a neck on TB. Not for the faint of heart and certainly not for a brand-new, still in warranty instrument.