Chopping up a pallet of sod is going to take a boat load of time. I would layout a bunch of pieces and cut it with edger, that will at least knock down the time spent whacking and hacking. FYI sod is usually only good on a pallet for about 3 days tops if it is in full sun as the inner pieces will start to bake, it will last longer if you lay it out sooner than later. The sod companies here use machetes when laying full pieces, larger bolo style ones, never seen anyone use a carpet knife lol.