WTH? I mixed up a small 3" round x 1/2" pad of 3M Bondo and mixed it up with a 3" stripe of hardner as described in instructions. Mixed it for about 2 minutes and by the time I was slapping it onto the dent it was not even spreading anymore, just clumping and way harder than I remember it. Whats the official ratio of hardner to filler? I got a scale and will use about 3/4 the hardner called for next time for some longer set up if that works. Im putting it on a horizontal surface so I can have it a little runny as long as it gets into the screen. Im patching a 3" rust hole (double wall, top is rusted through) in my little beater truck.