i built this since my brother does masonry (rock work) on houses, buildings, and yards. all the time he needs a rock saw with two saws in one. so i built it like i was going to build a tiller but put on saws instead. this would be a good sellers at the lego store.
About this creation
it would be a powerful engine to power this machine. its hard to beleive but they make giant saws for excavators in the rock mines. then they just pull the rock out of the ground.