I got to thinking yesterday(not my greatest skill) and thought about building a stump jack.I know some of you woodturners really love to use the burl on the stump end of the tree.Any thoughts? advice?
A Backhoe comes to mind.
You just scratch and claw at it, and it comes out.
When I was working in overhead, we had these super heavy duty cast iron jacks that would pull a power pole in areas you couldn't get a truck. Monsterous things! (And now I wonder why my disks are squashed. :P )
Just back from looking for a link for you. Didn't find one.
These jacks were pretty strong mechanical type mechanisms and had a chain grab on the top.
The were rated at 20-30 tons or more.
Ahh... the good old daze. :7
I have seen them in books and saw one in use on TV,some show about the Erie Canal.They are nothing more than two large wheels and a slightly smaller one in the middle.The one I saw on TV was an axle about 10 feet long.A heavy chain is attached to the axle and hooked to the stump.The axle is up on an A-frame at each end.A rope or cable is wound around the smaller wheel.When the rope is pulled it wraps the chain and pulls the stump out of the ground.The host of the show said they used mules to do the pulling but that one had 6 men pulling the rope.They pulled a Cherry stump about 2 or 2-1/2 feet in dia.like pulling a garden stake.I'm sure it helps to do the work in wet weather.
This is just a way of increasing mechanical advantage from a time when there were no portable hydraulics or powered equipment to do such jobs. Unless you are interested in creating it just for the nostalgic value, I'd suggest using a backhoe, frontloader, or similar piece of equipment. It will be faster and safer, plus you'll be able to pull much larger stumps. If you are planning on pulling several stumps to be processed for the wood at the rootball, it might even be worth it to rent or hire the equipment. You could do more in a day than with such equipment than you could accomplish in a week with a modern version of the stump puller in your illustration.
However, if you are set on making a stump puller then you might want to consider co-opting the idea of gaining a mechanical advantage then updating it with modern mechanisms. The first thing that springs to my mind would be to constuct a similiar trailer like device that straddles the stump. Mount a chain hoist or an electric rail hoist (my choice) to a center member set high enough to give the clearance you need. Attach chains to the stump, hook to the hoist and pull away. Voila! Same concept... less work. Just keep in mind that these hoists are capable of lifting several tons easily and the superstructure will have to be stong enough to stand thoses stresses.