string core breakage occurs at intonation saddle, why?

[hewo]

does anyone know the reason why the 24 roundwound pure nickel wrap string core breakage occurs right at the intonation saddle ?

i have not seen this occur and was wondering if anyone knows the real reason.

i had thought maybe, excessive plucking at this area might be over-doing the string's capability to handle this proximity stress.

responses are welcome.
thanks.

[Steve A.]

does anyone know the reason why the 24 roundwound pure nickel wrap string core breakage occurs right at the intonation saddle ?

i have not seen this occur and was wondering if anyone knows the real reason.

i had thought maybe, excessive plucking at this area might be over-doing the string's capability to handle this proximity stress.

responses are welcome.
thanks.

hewo:

I have not run across that problem myself. Perhaps you can give us more information like what brand and the name of the set that you use. Also, is the core round or hex shaped, and what is it made of.

The problem could alternately be with the bridge and saddle. So we need to know what brand guitar and the name of the model as well as the brand and style of the bridge with all of the details. Your playing style and type of pick used is also important. BTW does this guitar have a whammy bar that you use regularly?

Once you supply that information we may be able to help you with this problem.

Steve Ahola

P.S. I'm not sure if this is applicable for a 24W string but for the plain strings if one of them breaks right at the saddle I will dress it just a little piece with folded emery paper. If I do that every time the string breaks there, the problem goes away. (I can't see how the core could be damaged by a small burr on the saddle.)

One other thought: if you have a Tune-A-Matic bridge and matching tailpiece, sometimes when you lower the tailpiece for more sustain it can make the angle of the string going over the saddle too sharp.
The 24W is pretty much the smallest wound string used on an electric guitar. So the core and wrap would be the smallest of all of your wound strings and it would be more likely to break.

[David Schwab]

What Steve said.

Usually it's caused by a rough spot in the saddle's groove.

And if it is a Tune-o-matic having the tailpiece all the way down also causes problems and does not increase sustain at all. I've seen TOM bridges collapse from that as well as the tailpiece studs pulling out of the body.

[Gibsonman63]

Old School Trick

We used to take the stop piece on a tune-o-matic bridge setup and screw it all the way to the body of the guitar and then wrap the strings over the top. Supossedly, you get better sustain without creating too much angle going over the bridge saddles... We the sustain part is supossed, not the angle part.

The strings will leave marks on the stop piece. If that is an issue for you, you may want to buy a replacement and keep the original in the case.

[hewo]

string core breakage occurs at intonation saddle, why?

thank you everybody for your responses.

1. i carefully inspected the channel in that saddle and it's pristine (20X magnification).

2. the strings were all tossed and replaced with a pack of "kaman electr-2ix 6 double play process tm 5135 nickel electric extra light $2.99 " that i had stored in my garage closet. must be really old stuff based on that price sticker.

3. the kaman's are cylindrical core but the pure nickel wrap darco (martin's) roundwound extralight's were hex core. i verified this using the magnification viewer (sunvisor type, my eyes are getting old).

4. the guitar is a "sunburst archtop" korean slammer series by hamer and is dated 94. it is rather well setup. the pickups were changed. the stop bar tailpiece is in fact bottomed and has been this way since 94.

5. the darco set went on in 94. but still it shouldn't have failed. guitar designed considerations for cyclic fatigue cycles, preload tension, traction over the saddle, assure us that the core should not break. otherwise design would have changed (evolved).

6. a view the fractured surface under the sem and photography of the "necking" of the diameter where failure occurred could possibly tell the mode of failure. at the separation, in the centre of the core would be the key as the appearance would be different if cyclic fatigue initiated embrittlement as opposed to "taffy" like appearance of an axial stretch failure.

7. string breakage caused me a great distress. i did not have a spare guitar. consequently i ended up dancing on stage for an hour! our lead guitarist tossed me a fender pack but i did not want to change out the string being uncertain of compatibility under setup conditions. the impact of a broken string during performance must be prepared for - this is my lesson to learn from this experience.

[defaced]

I love it, SEM string breaking analysis. I wish I still had one of those at my disposal (with EDS). What fun they are.

But yea, I think you could tell the fracture mode provided the end of the string isn't gunked up from contaminants.

[hewo]

sem and metallurgical failure analysis

mike,

1. we would agitate the specimen in an ultrasonic tank using proper solution.
2. then we'd mount it to the specimen substrate, sputter palladium over it's surfaces and then view it.
3. after that if etching was necessary (to inspect for voids and or ingredients not suppose to be in the mixture recipe metal) we'd view the grain boundaries as they can reveal a wealth of information as to what has happened.
4. i believe the string broke because of too much applied plucking near the intonation saddle. common sense dictates that the forces (stress) acting would mount appreciably (twice normal expected values). repeating such torture would likely fail it as steve pointed it is a rather thin core without much protective wrap bulk to buffer the impinging saddle.
5. imagine. this is actually where the energy of the vibrating string transfers a portion of energy into the guitar structure. were you to monitor the structure of it's energy "felt" this would reflect that portion of energy transferred out of the string and into the structure. an infinitely rigid structure with infinite mass would claim zero imparted transfer energy from the string.

[David Schwab]

We used to take the stop piece on a tune-o-matic bridge setup and screw it all the way to the body of the guitar and then wrap the strings over the top. Supossedly, you get better sustain without creating too much angle going over the bridge saddles... We the sustain part is supossed, not the angle part.

You don't get better sustain with the stop tail all the way down. You also don't get more sustain with the strings running through the body.

It's a myth based on nothing. Increasing the pressure on the saddles also wont increase sustain. If you think about it, there is no reason why it would work.

More than anything else, sustain is a factor with how stiff the neck is, and secondly the energy of the string not being absorbed by the body/neck.

I had to repair a $10,000 LP Stringer that had one of the tail piece studs pull out because someone screwed it all the way down to the body. It's not how that bridge system was meant to work.

But getting back to the original post, string breakage at the saddle is always caused by a burr in the groove, or a poorly shaped groove, even if you can't see it.

Just sand it smooth with some 400 grit and it will be fine.

I often pick my strings REALLY hard with extra heavy picks, and I never break strings unless the saddle grove is funky. I haven't broken a string in about 8 years.

[axpro]

Hey Hewo,

whats the break angle like? and what is the string tuned to. If there is no Burr, but the core is breaking, it could be due to excessive break angle ont he TOM. if it hits the "flat" side of the bridge saddle first, instead of the sloped side, that can also be a problem, especially when you have a sharp break angle.

I come across this fairly often with players who have TOM/STOPTAIL setups, and lower the stoptail tight against the body trying to increase sustain. If you look at the pro players who do that (like Zakk Wylde) they routinely bring the strings up and over the stoptail, to reduce break angle on the string, while keeping the tailpiece tight against the body

[Steve Conner]

I don't break strings often, but when they do let go, they always break at the saddles, on every guitar and bass I've owned. I usually change the whole set when one finally goes.

I think smallish saddle points give better tone. I don't like PRS's wrap-around stoptail thing where the strings go into big grooves for about 3/4", I think it dulls the tone, and they make dark-sounding guitars already.

If you've had the same strings since 1994, that's incredible. Do you play that guitar often?

[axpro]

If you've had the same strings since 1994, that's incredible. Do you play that guitar often?

lol


all my PRS guitars (save one) are trem equipped. I don't actually "use" the trem...ever.... but i like the difference in midrange tone versus a wrap around hardtail.
Last 2 or three times i broke strings, it was at the headstock... mind you, that covers about 4 years for me.... many guitars+non acidic sweat= strings go dead far before i break them.

[Gibsonman63]

Sure, rub it in!!!

I am lucky if I get four gigs out of a set of strings. I did seven outdoor gigs last July here in Houston. I was changing strings weekly on my main guitar and every other week on my back-up and my tune-down guitar.

That being said, the fingers do move better in warm weather than inthe cold.

[axpro]

I am lucky if I get four gigs out of a set of strings. I did seven outdoor gigs last July here in Houston. I was changing strings weekly on my main guitar and every other week on my back-up and my tune-down guitar.

That being said, the fingers do move better in warm weather than inthe cold.

Waitasecond, you southern boys MOVE your fingers?!?!?!?



Like i said, LOTS of guitars, non acidic sweat, and currently not gigging. I had 5 guitars at my band practice space so i wouldn't have to play one all night lol! But sincei am a guitar tech, i tend to play heavily customized guitars i build myself.... rebuilding a horrible garbage guitar into somethign sweet only costs time, since i have lots of pickups and parts laying around....

[Gibsonman63]

Kind of funny, really. If you watch closely, the Reverend Billy G never seems to move his fingers. But between the open tunings and the hybrid picking, he has a lot going on that's hard to see.

[David Schwab]

I think smallish saddle points give better tone. I don't like PRS's wrap-around stoptail thing where the strings go into big grooves for about 3/4", I think it dulls the tone, and they make dark-sounding guitars already.

It's the pickups. I play in a band with a guy that has two PRS guitars, and they sound nice and twangy unplugged. The pickups are dark sounding.

The material the bridge is made from will alter the tone, but not the way the strings are anchored. Lighter bridges made from aluminum sound brighter than something heavy like brass. Brass is dull sounding.

I'm lucky that my hands don't sweat ever, so I can keep strings on guitars for almost a year. But I like fresh sounding strings better.