The mechanical tree jack!

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ChrisF

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Not sure if this deserves it's own thread, but it gets one anyway.

My boss ordered a mechanical tree jack for us last week, the swedish-made Granfors Stalpen, and today I got to test it for the first time.

While it might seem silly or unneccessary, it's perfect for what we do and the size of trees we get. There's no room for a hydraulic jack in the trees we cut, and wedging them against such severe lean as we're up against over the next week isn't something we're inclined to do.

My impression of this thing is that it's very well built, sturdy, and makes my job a heck of a lot safer and easier.

Here are some vids of me using it. The last one makes me wince just watching it, the tree was a total pig and my ridiculous half-hearted attempt at yanking it loose from the tree when it started to go is embarrasing, but you live and learn.

[video=youtube;OT0jGmo4Vng]http://www.youtube.com/watch?v=OT0jGmo4Vng[/video]

[video=youtube;TMhDIxk2pDM]http://www.youtube.com/watch?v=TMhDIxk2pDM[/video]
 
The last two vids:

[video=youtube;E2iCFdrbVy0]http://www.youtube.com/watch?v=E2iCFdrbVy0[/video]

This is the embarrasing and scary one:

[video=youtube;znjHdFpK3Dc]http://www.youtube.com/watch?v=znjHdFpK3Dc[/video]


And ofcourse the all-important tree-kill-pose, relieved after a nervous and tense session of jacking, cutting, and jacking some more on that last one:

img1497zt.jpg
 
how does that thing work? i think if i can figure that out id be inclined to build one myself. seems to work really well. it looks like it would be well suited to my timber in the area.
 
Not quite sure how to describe the mechanism in english, so I'll just steal the description from the website of Gransfors Smide, the manufacturer:

STALPEN is a rack-and-pinion based mechanical jack intended for use as a mechanical aid in tree felling. STALPEN can be used to support trees or other objects that need to be stabilized or felled in the right direction. STALPEN has a safety crank consisting of lamellae with friction members. A ratchettype freewheeling clutch prevents the crank from backlashing and makes it possible to turn in both directions without the need to touch the ratchet that holds the clutch.

There you have it.
 
The last two vids:



This is the embarrasing and scary one:




And ofcourse the all-important tree-kill-pose, relieved after a nervous and tense session of jacking, cutting, and jacking some more on that last one:
attachment.php



Thanks for the video on that !
Always wondered how effective a tool it would be .
I think I'd still have a rope on the tree if I was felling in risky areas .
 
Hey good movies Chris! Its interesting to see different tools in action. Yeah the one by the electrical deserved a line in it though with your camera man tugging on it. Otherwise not bad and your scary one looked fine to me. The first two I thought, hmmm I've pushed over bigger ones than that by hand. The second two were a little meatier. I could see where that thing could come in handy on small snags where you don't want to shake stuff loose from the top by pounding wedges. Good show!
 
So how many trees have you done so far? Every tool I have ever used, I had some regrettable outcomes early on. I have survived them all, but not always as a consequence of wisdom. Yeah, it looks like a good tool. I could have used it on one tree. I ended up with far too little hinge before it went down.
 
I have worked with Brothers that could stand on the hood of the TJ and hump over 20'' poplars like they where nothing. . .

My good buddy Doug, an old timing black boy that clean jerks 500 lbs in the morning like light butter on crepes. he puts the rest to shame. 7 years older than me and tha boy grew up in a house with no running water. . .
The man is tough, like me. . .




We counrty. . .
 
It looks like a nice and handy and very controlled tool, now I can say something productive since I've now actually watched the videos....
 
cool l;ooking tool, for years now I have been using a 6ft long tube of steel we made to fit over the shaft of my jackall bumper jack. we welded a v shaped teeth to the top to penetrate the trunk safely. I throw a chain around the base of the tree to prevent the jack sinking into soft earth , or kicking out. the jack will push 4000 pounds. works just fine but it is a little heavy to carry around, however it is cheap and easy to make.
 
Chris, If you ever need to buy a jack your own, check out "Stalpen". I have got one, made by our beloved neighbours in Sweden.

IMG_3379.JPG


The mechanism is different, it is cable-driven. It means the tool needs more maintenance and spare parts, but: 1. The foot is different, it does not sink into the soft earth so easily and 2. the crank is lower, so you can use your legs spinning the crank. Unfortunately Granfors's jack, if you are using it a lot, makes bad things to your right shoulder and elbow.

IMG_3382.JPG
 
Samlock, it's the Stalpen we got, but not the cable-driven one you describe. Huh, weird.

Haven't had a need for it so far this week, but out it goes again tomorrow.

I'm in love with this piece of steel though, it absolutely rocks.
 
Did I say Stalpen? I meant to say RH-pusher. That is what it is. Oops.

Maybe I should quit being sober.
 
Funny guy Sam.
When I saw mechanical jack, I remembered the old screw jacks or even worse, the geared ones that looked like they were made from a truck differential.
 
Funny guy Sam.
When I saw mechanical jack, I remembered the old screw jacks or even worse, the geared ones that looked like they were made from a truck differential.

Have you read the book, "Somtimes a Great Notion"? Great descriptions of those nasty screw jacks....I thought of the same thing when I saw the vids. Nifty tool.

ps- the book is better than the movie....Ken Kesey is good stuff
 
Have you read the book, "Somtimes a Great Notion"? Great descriptions of those nasty screw jacks....I thought of the same thing when I saw the vids. Nifty tool.

ps- the book is better than the movie....Ken Kesey is good stuff

I aspire to have a tenth of Kesey's talent.

paccity lives near that old house, I gotta see it.
 
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