O-200's in Cessnas and A-65's in Cubs are great ice generators. Nothing to worry about but a good blast every 15-20 minutes will keep you flying.
I flew through a light rain shower in my Cub with a wooden Evra prop. Fortunately it had brass leading edges so it was just the varnish that was stripped off! I heard of a chap who flew F1 racers who fitted a wooden cruise prop to fly to the races. He flew through some reasonably heavy rain and lost 1/2" depth off each leading edge from the boss to the tips.