How to Make a Log Raft

Gather or cut 10 logs or timber (spruce trees are best) about the same size, 12 feet works well. You'll need four shorter logs, about 7 feet long. If you don't have access to this much wood, you can scale down the size of the raft and use as many logs as you can for the deck.

Place 2 of the shorter logs on the ground about a foot shorter than the length your log raft will be. So, if you have 12 foot logs, you'll lay the shorter ends about 11 feet apart, marking the ends of your raft. When you lay your deck logs on, they will be perpendicular to these.

Use an axe or knife to carve off the curve of those shorter logs and make the tops flat so that when you lay the deck logs on top, they will rest squarely on them. In other words, you are creating a long notch that the group of logs will fit into to make your deck.

Put down the rest of the logs, stretching from one of the shorter, notched ends to the other. These will form your deck. They should hang over the notched end logs a little, not stop evenly with them. The logs should fit together tightly, with no wiggle room.

Carve down one side of the 2 remaining shorter logs, and lay them carved side down on top of the deck, at the ends, directly above the first carved logs. You've sandwiched the deck logs between the 4 carved logs, to ensure a good, tight fit.

Secure the logs with rope by tying the 4 supporting logs to each other at a few points on the raft. You should also pick various spots to tie the deck logs to the supporting shorter, carved logs that lay perpendicular to them across the raft. In a survival situation, you'll probably have to find vines or flexible bark, or cut up some of your clothing to use in place of the rope.