enchant 1 weapon till u get a good number like +5+6+7
then try to enchant other weapons till get broken
the trick is get 2 broken one after each other then try the good one
and again repeat procedure two broken and then the good one
so that way u fit the 2/3 break rule :)
note: if 1 broken an the other dont doesnt count, HAVE TO BE 2 FOLLOWED BROKEN