Romotre said:How long would it take ... to build a raft?
That depends on a lot of things. What resources are available? Are you on a beach, and there is a lot of driftwood available? Is it dry? Are you in the woods, and there are trees around? Do you have rope? Nails?
Let's just say for saying's sake that you need a small raft, 5 feet wide by 10 feet long. You're in the woods, and you run across a stand of 25-year old lodgepole pine really close to the river. Barak, the party's dwarven fighter, can have a tree fallen, limbed and cut into two usable 6" diameter, 10 foot long logs in five minutes, accounting for a short rest break at the end.
Six trees need to be fallen, and one of the 10 foot logs need to be cut in half for the crosspieces. We'll call that 30 minutes overall, with one tired dwarf at the end.
Now, with all those flying wood chips and falling logs, the rest of the party had to stay out of the way, and couldn't do anything while Barak was cutting trees. Now they go to work.
They lay the two short logs (5' long each) about eight feet apart, near the river, parallel with each other. They put one of the long logs across the ends, and tie it on with hafts of the ubiquitous 50 feet of rope that every first-level adventurer buys. They repeat this step until all logs are tied on. Two guys are good with rope, and do the tying; two other guys are hauling the logs over, and so each log only takes about four minutes to attach. Ten logs make a five-foot wide raft, so that's 40 minutes.
Total time for raft building, 70 minutes, assuming great resources and no stubbed toes. Stretch it out from there.
JD