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Very new to the guitar. I borrowed an Oscar Schmidt OC11 nylon-string classical guitar, without an E-6th string and I bought a heap load of different weighted strings so I could try different types. However, the strings I bought are for guitars with bridge pins.

I just broke a string trying to make it work and I am even more worried about breaking the guitar.

Should I return the strings or can I make them work?

marked as duplicate by Bradd Szonye, Shevliaskovic, Dave, Doktor Mayhem May 16 '14 at 15:40

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

  • (This question came first, but the other one is asked more clearly and serves as a better signpost for the problem.) – Bradd Szonye May 16 '14 at 0:04
up vote 14 down vote accepted

Just to be clear, what you have are ball-end nylon strings, right? Because if you're planning on putting steel strings on a classical guitar, I'll have to advise you against moving forward. The instrument is not built for steel string tension.

If they are nylon strings, on a standard classical guitar, has a tutorial on the right way to restring your classical guitar, if you have the right strings. But, if you're just putting in a ball-end nylon string, you should be able to run it through the hole in the bridge just fine and get your classical guitar on without doing tying.

That's if it's ball-end nylon strings. If not, stop and get other strings.

  • 8
    Big fat +1. DO NOT attempt to put steel strings on a classical guitar (as the Oscar Schmidt OC11 is) unless you're performing an experiment testing the playability of a guitar that has folded like a cheap card table. – Alex Basson Dec 22 '12 at 3:56
  • Well, they are definitely not nylon. The package says phosphor bronze. Here are they are:… From the Amazon page, it looks like two of the six are steel. – plntxt Dec 22 '12 at 14:54
  • 1
    Those are not the strings for this instrument. – Dave Jacoby Dec 22 '12 at 22:57
  • 2
    I promise you, those strings are steel at the core, with phosphor bronze wraps to add mass without much affecting flexibility. It is neat stuff, but you have to build the instrument to account for it. Heavier bracing in the body and a truss rod in the neck. The tension between the bridge and neck on an electric guitar is about as many pounds as you are, so they need it. It'd probably sound amazing for the few moments before it falls apart on you. – Dave Jacoby Dec 22 '12 at 23:15
  • 1
    An acceptable acoustic guitar starts at $100. Strings start at $4. Match the strings to the guitar, not the other way around. – Dave Jacoby Dec 23 '12 at 13:57

Remove the steel strings immediately. They will permanently damage your guitar.

Do not use light-gauge steel strings either. You should only use nylon strings on this guitar.

Steel strings put much more tension on the neck of a guitar compared to nylon strings.

Guitars designed for steel strings have very stiff, strong necks with a metal truss rod inside the neck designed to counteract the additional tension from the steel strings.

Classical guitars designed for nylon strings generally do not have a truss rod in the neck, and the neck is built only to withstand the lower tension of the nylon strings.

Furthermore, the top of the classical guitar and the bridge are braced underneath only to withstand the much lower tension of the nylon strings.

If you keep those steel strings on your guitar, the neck will permanently bend and warp, the top of the guitar will "belly up" and warp, and the bridge will eventually rip loose from where it is glued to the top of the guitar, taking a good deal of the wood of the top of the guitar with it. When these things happen, then your guitar will be ruined. It will not be feasible to repair the damage.

Never, never put steel strings on a classical guitar built for nylon strings.


I did the maths based on data from string sets at the D'Addario string company web site.

A typical set of regular-gauge steel acoustic guitar strings puts 179 lbs (81.3kg) of tension on a guitar.

A typical set of nylon strings puts 83.6 lbs (37.9kg) of tension on a guitar.

Therefore if you put steel strings on a classical guitar, you are more than doubling the amount of tension and strain that the classical guitar has been built to handle.

  • This is a repeat post of an answer I made on another question on this site, but I thought it important enough that I duplicated it. What the questioner was trying to do, not knowing any better, is very dangerous. – user1044 Sep 1 '13 at 11:12
  • What information did you find about nylon strings and tensions? As noted on another question, I'd like to find some nylon strings that would work well for a 2+4 bass/treble split [with the fourth string being an unwound "D"]. Also, out of curiosity, what sort of string gauge were you assuming for the steel strings? I would expect that a set of 8/38 strings would probably only require about half the tension of a set of 12/56; there may not be any overlap between the lightest steel strings and the heaviest nylon strings, but I wouldn't be surprised if they were close. – supercat Dec 26 '14 at 22:22
  • I have referred to this string tension reference PDF from D'Addario many times on this site. It covers steel-string and nylon, and more. Check it out. – user1044 Dec 28 '14 at 0:42

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