The Collings Forum

my warranty card say 12 to 53 gauge strings are required. is it dangerous to use 13/56 guage?

I think it depends on the type of bridge you have: a pyramid bridge is up to 12s and a belly bridge can go to 13s. Probably best to check with Collings though- consequences of too much tension could be nasty!

thanks, it is a belly bridge

Here's what the Collings website says -

"For small bodied guitars (Baby, OM*, 0, 00, 000, C10), we use:
J16s - light gauge (.012, .016, .024, .032, .042, .053).

For large bodied guitars (D, CJ, DS, SJ, Archtop), we use
J17s - medium gauge (.013, .017, .026, .035, .045, .056).

*An OM should be fine with medium gauge strings. Due to the footprint of the "belly" bridge, there should be plenty of glue surface."

Could use a mixed gauge set as I have done for years on my pyramid bridge C10. Medium plain strings with light wound strings such as Elixir HD Light .013 - .053. Good balance for fingerstyle playing.