yes, but you would need to take the guitar apart and install bracing. which would make it sound crap, due to materials/body size. just don't do it.
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you can put acoustic strings on, it jus sounds reallly sharp,
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Quote by AshDoro
you can put acoustic strings on, it jus sounds reallly sharp,

Didn't you just read anything above you? The increased tension of steel strings would snap the neck. Many classical guitars don't have a truss rod. At the very least, it would probably bow the neck pretty bad, and it be pretty unplayable.
^ That will cause the neck to bow like nobody's business.

A majority of classical guitars aren't build with truss rods, and at the very least have a strip of harder wood to act like a truss rod. This is because nylon strings have very little tension compared to the steel string acoustic strings.
 |Classical | Steel stinged |
E|  7.08 kg |   10.57 kg    |
B|  5.12 kg |   10.57 kg    |
G|  5.23 kg |   13.70 kg    |
D|  7.55 kg |   13.83 kg    |
A|  6.79 kg |   13.56 kg    |
E|  6.27 kg |   11.79 kg    |

Total (Classical, .28-.43)    | 38.04 kilograms of tension
Total (Steel String, .12-.53) | 74.02 kilograms of tension

Both are very standard guages of strings for each guitar.

EDIT: There's 35.96 kilogram difference in tension. Almost an 80 pound difference.
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Last edited by Will_Minus at Feb 21, 2007,
I have steel strings on my nylon acoustic.. It's holding up okay for about 6 months now. It has ZERO tuning stability though. It's only a 3/4 though so maybe since it's shorter that gives it a bit more strength.
It will cause a "bump" in the soundboard and the soundboard will tend to dip in towards the soundhole. Not to mention any problems with the neck

In short, not a good idea.