Alvarez mf60OM.

they use a different bridge which purports to increase string tension.

I’ve been doing a lot of classical with nylon strings and my parlour with 13-53 silk and steel but I’ve had 12-53 and 12-54 on another OM with no problems.

this Alvarez comes with D’Addario EXP16 12-53. 
practised maybe an hour and my finger tips are grooved and sore.

Is this unusual. Just down to a new set up ?

I have some 10s and 11s which I’m just going to have to try on this guitar until I get some mileage in.

Dave L

edit 12-53  156.4lb. 11-52 151.8lb   
11s do feel better on my fingers