Thursday, December 10, 2009

Felling

I appreciate drawings like this the way other people appreciate fine wines. (Large scale drawing here.) I can stare at them for a long time and inevitably I will start dreaming about making something similar.

Also, this sure looks like a clever contraption. Due to some nutty concept of ritual cleanliness I do not use a chain saw to obtain firewood, but this machine would pass my fundamentalist views on what is sylvian kosher and what is not.

But surely the blade would get stuck in the kerf? Saw a horizontal cut and the weight of the tree will normally pinch the blade until it can only be coaxed out with brute force and very foul language. I am skeptical about whether this device was ever used in the real world.

(Illustrations lifted from the always interesting notechmagazine.com.)

9 comments:

Andrew said...

pair it with a tensioned rope or cable opposite the kerf?

i, too, love these kinds of drawings. jan adkins has some good books that might be up your alley

Andy in Germany said...

I concur with Andrew- orperhaps wedges in the kerf? (I haven't a clue about this sort of thing) mind you, I know a man who does. Maybe I can ask him?

Oldfool said...

If the tree is properly notched on the side opposite the saw cut then the kerf should open as the cut is made and the tree should fall away from the saw. Should is the key word as shape of the tree and wind influences the outcome. Should work as good as a two man saw and I have seen many tree cut down with a two man saw.
Things didn't always work out as planned.
This is still a two man saw and as a labor saving device I see no advantage except that it could probably be operated by two boys because of gearing. A two man saw is really hard work.

dave said...

the same mechanism which pushes the saw deeper into the cut is also pushing the structure above the saw against the tree, which should prevent the saw getting stuck, I think.

Oldfool said...

Oh yeah, I forgot to say thanks for the notechmagazine.com link. Now I have something to waste away the rest of the day with.

Northmark said...

Thanks for these comments! I wonder if everybody here might be right. There is a tensioning mechanism. And wedges and notches could come into it, but if you need that, you might as well fell the tree the old fashioned way instead. I think David is right about the mechanism that's supposed to push the tree, but is that an accident waiting to happen or what.
Still, those guys back then sure knew how to draw.

I have never used a two man saw. I have no rhythm and imagine I would make any partner extremely angry.

Lynn said...

I have never seen anything like that for felling, but turn the cutting blade vertical and you have what is called a drag saw and was used for bucking logs. They are usually powered by one of the old fashioned large flywheel, low RPM stationary engines.

skimbo said...

I am just wondering, though, would it not be easier to carry an axe or a saw around in the forrest rather than this machine?
It looks a bit heavy.

Northmark said...

Skimbo: Certainly! To quote Theodore Roszak in his "Where the Wasteland Ends" (1972):

"How much of what we readily identify as 'progress' in urban-industrial society is really the undoing of evils inherited from the last round of technological innovation?"

Thing is: If it's got gears and is human powered, it always seems interesting to me no matter how useless and cumbersome.