What is required
The work can be done with a minitractor, the usual car traction is quite enough. For the tackle, a cable, metal blocks, a rope, tape slings or tugs should be prepared. The cable length and the number of blocks should be selected taking into account the necessary effort to uproot the stump.
First you need to understand what a chain hoist is. This device is assembled from fixed and movable blocks sequentially enveloped by a cable. Such a kinematic scheme allows to increase the pulling force at times, the more blocks - the greater the force. Each block doubles it, but the length of the cable increases. For example, the stump must be shifted by one meter, this requires a force of about 10 tons, and the minitractor has a traction of only two tons. It is necessary to connect five blocks, and the cable length without taking into account the tension of 10 meters.
In this example, a mini tractor with an output of 18 horsepower and a 35: 1 chain hoist are used. That is, in fact, the pulling power of the tractor will be increased by 35 times.
Throw around the hemp a ribbon sling of the appropriate length, with a metal link connect it to the ribbon cable and the first block.
Rope or metal cable go around the roller of the first block, put it on the second, then again on the first and so many times how many elements each block has.
Tie blocks to nearby trees, use ropes or cables. The main condition is that they must be durable and withstand the load. In our case, the pulley consists of seven rollers. All elements must be placed approximately in the same plane. The last block should be tied taking into account the direction of movement of the tractor.
Start a mini tractor and gradually pull the cable.
The system takes its place, taking into account the height of the blocks, the cable is pulled. If the final effort is enough, the stump will begin to break out of the ground.
Check the condition of the chain hoist, if everything is normal, then continue to uproot the stump. If there is no room for tractor movement, then fasten another block and change direction.
Disassemble the chain hoist, load the uprooted stump onto the trailer and take it away from the site.
Blocks set too low rise and damage the bark of the trees to which they are attached. It is possible to substitute between the tree and the cable trim boards, they will protect it from severe damage.