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pennywise86
October 17th, 2005, 08:12 PM
I'm wondering how you would go about contructing a small raft in the woods to cross a river. Obviously you would need long pieces of wood, but what could you use to bind it all together? The way I have it right now is that the characters strip bark from saplings and soak it in water overnight for it to strengthen (I have no idea if this works or not, it just seemed like a good idea at the time) and use the lashes to bind the raft. Is this possible? If not, how else could I do it?

Snowie
October 17th, 2005, 08:29 PM
Let's BRANCH out a bit on your idea:

The bark is soaked to make it pliable and so that when it dries, it shrinks, thus holding the joined poles/planks more tightly. Fresh bark would likely not need soaking. Strips of leather were often used to lash rafts (after the soaking method you mentioned was used).

You might wish to have the river-crossers use a pegging method to hold the raft together. What sorts of tools do they have? They'd need something along the lines of a knife and an awl, at the least, for the pegging method. Notching methods would require the use of a knife and a plane (the knife could be used as a plane if long enough and with a non-serrated straight blade).

Splits can be made in the ends of green wood logs and a thinner plank forced in, for a temporary raft. Picture two sapling logs, with a split in each end, and two planks/thinner saplings, in a rectangular formation, with a few cross-pieces balanced on top. Very unstable. "Weaving" a raft with a variety of long branches/planks would also work.

A raft of ideas -- more than you ever wanted...

pennywise86
October 17th, 2005, 08:40 PM
wow, you really know your raft-building. As for what they have: an axe, strips of bark, and a coat they can shred apart if it comes to that, and a strong need to cross the river. What do you figure is the fastest way for them to build a sturdy raft to cross across? I could maybe see the peg idea working, but I need more details about how something like that would work.

Snowie
October 17th, 2005, 08:59 PM
No, no, the pegging would be laborious and take too long, if they're in a hurry.

They probably ought to sacrifice the coat and cut it into long strips. With the axe, fell a bunch of saplings, unless dry logs are nearby. Use the cloth to bind the frame of the raft, then lay logs/saplings crosswise and bind with more cloth, or if the cloth has been used up, the bark.

The problem with green wood is that it's not particularly buoyant. How hefty are these guys? They may have to pole across with the raft actually submerged underneath their feet! I don't know how familiar you are with boating, but with Lund boats, they can be filled with water, and they will sink to the gunwales, but they will not sink below that. They are still somewhat manueverable (sp) even submerged. It would be nice if there were two dry hefty logs for ballast under the raft. Or two bloated bodies of enemies to tie under there.

Expendable
October 18th, 2005, 12:54 AM
You could make rafts by making large bundles of reeds if you've got some rope or some good strong vine. Check this wilderness survival (http://www.wilderness-survival.net/chp17.php) site out for improvised rafts.

Or look at this corracle (http://www.quinnipiac.edu/other/abl/etext/irish/pictures203/p143.html), the Celts used this simple one man boat for years.

Or you could just find a large log and float across on that if the water's too deep to ford. But you'll need to dry off if it's cold.

pennywise86
October 18th, 2005, 11:21 AM
Thanks, Expendable, but the corrale looks as though it would take too much time to build. As for the raft and using dried wood. There's three of them that need to cross, two boys and a man. I'm wondering, would you be able to dry the wood over a fire? Anybody know the process?

Snowie
October 18th, 2005, 02:08 PM
I think it would take far too long to dry it over the fire. I'm talking greenwood here. If they have seasoned wood that is just wet, they wouldn't even need to dry it. It would have excellent buoyancy even wet. In most woods, there's plenty of seasoned wood on the ground. Just remember the physics of buoyancy, in that buoyant force minus weight of object = the net force upon it. When the weight of an object is greater than the buoyant force exerted upon it, it will sink. But the buoyancy is determined by more than sheer weight. Rather, the amount of water displaced by the object is also important. That's why a lump of coal that weighs 1 newton will sink, but a piece of styrofoam that weighs 1 newton will float. Thus, the size of the raft is not the absolutely most critical aspect, but rather the buoyancy of the materials and the "footprint" of the raft in relation to its weight.

Word of advice: Don't let your story be derailed by becoming so tangled in tangential details that you lose your momentum to write and create. ;)

pcarney
October 19th, 2005, 12:03 PM
Dunno how cold and wide your river is, but perhaps it would be easier (and faster) if your protags built a small raft to hold supplies, then swam alongside it?

BTW- I agree with Snowie- never let reality get in the way of writing!

Expendable
October 19th, 2005, 07:52 PM
Are you looking to make a birchbark canoe (http://www.squeedunk.com/building.htm)? Like the Native Americans? They'd cut the birch bark high and low and peel it off the live tree as a sheet.

But making a birchbark canoe or raft would take a while. It would be faster to lash some logs together.

You could ford the river instead. All you need for that is some good rope. Have the man tie it around his waist and wade/swim across the water, then tie the rope to a tree. Have the boys tie the other end. Then they can cross, holding onto the rope. Then the man can cross the river again, untie that end of the rope, then swim back holding onto it.

pennywise86
October 19th, 2005, 08:04 PM
the scene is already written, now I just wana make sure it's as believable as possible. In the end, I suppose I won't change that much, just perhaps have them use wood from the ground, though Expendable's suggestion of fording it could work also.

Thanks, guys!