Silvey Tree Jacks
The high value of today's timber makes broken logs expensive. Logger's also demand accurate falling so their machines can move the wood efficiently. Even increasing environmental requirements has made the faller's job more difficult. Fortunately, they have a tool that helps them meet these challenges. That tool is a Silvey Tree Jack.
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This tree is being cut by Nick Minahan on a job site in Oregon. Notice the rams he's placed in the back of the tree. This jack lifted the tree and allowed Nick to fall it exactly where he wanted it. |
Tree Jack History
The
first tree jacks were simple hydraulic "bottle" jacks. These jacks are
still used today in truck shops and anywhere a high lifting force is
required. Early on, hydraulic jacks to help direct where trees fell
was effective, but timber fallers didn't like lugging around
these
heavy jacks. It was especially difficult on rough ground.
Using conventional bottle jacks presented other problems. For one, the surface area on the top of the ram was small, so lifting a tree usually required the used of jack plates. This caused the faller to carry even more heavy tools. The people at Silvey (the people who invented the chisel chain grinder) had a great idea. They would build a lightweight tree jack out of aluminum. This jack needed the lifting capacity of an iron bottle jack, but would be a fraction of its weight. It would also have a small jack-plate attached to the top of the ram with springs -- eliminating the need for separate plates in most cases. The Silvey tree jack was born. Today's jacks can be easily carried from tree to tree, yet are powerful lifting machines.
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Single Unit Jack
| Jack Type | Hi-Jacker |
| Lift Capacity: | 45 Tons |
| Lift Height: | 4" |
| Cylinder Diameter: | 3" |
| Weight: | 26 lbs. |
| Oil Capacity: | 1 pint |
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This is a Silvey Tree Saver jack setup. It consists of two rams and a pump/pack unit. The two rams fit sit on a small shelf on the pump/pack unit. Rubber straps hold them in place so the whole jack set can be carried on a timber faller's back -- leaving his hands free for additional tools or stability. |
Pack Style Jack
| Jack Type | Tree Saver | Little Feller |
| Lift Capacity with Two Rams: | 124 Tons | 70 Tons |
| Lift Capacity of Each Ram: | 62 Tons | 35 Tons |
| Lift Height: | 5 5/8" | 4" |
| Cylinder Diameter: | 4" | 3" |
| Pack Weight with Two Rams: | 59 lbs. | 39 lbs. |
| Oil Capacity: | One Gallon | Two Quarts |
| Hose : | 10' Standard | 10' Standard |
| Optional Hose Lengths: | 25', 50', & 100' | 25', 50', & 100' |
Overview
Silvey tree jacks come in two styles: A back
pack unit (with two separate rams) or a single unit with the pump and
ram combined.
Back Pack Jacks - Back pack jacks come with two rams and a pump/pack frame. The pump/pack has shoulder straps on the front panel and serves as a pack frame. Rams nest on ledges in the frame and are held in place with elastic straps for "one trip" carrying. When its time to use the jack, the elastic straps are removed and the rams separated from the pump/pack. For small trees, the jack can be used with one ram. When setting up to lift a larger tree, the second ram is used for full capacity lifts. Up to four rams can be powered by a single pump.
Once a jack "seat" is cut in the base of the tree, the rams are placed in it. The rams are then connected by hoses to the pump with quick-connect fittings. Once connected to the pump, the rams are activated by a pump handle in the middle of the pack. A pressure gauge helps the faller monitor the lifting pressure on the tree and in the hoses. Colored lines on the ram also help the faller monitor the lifting height. A blue line indicates the ram is nearly at its full height. The next line is red indicating the ram is at maximum height.
After the tree has fallen, a valve on the pump is opened and springs on the rams return them to their starting height. The rams can be decoupled from the main hose and each other. They can then be placed back in the pack for travel to another tree.
The Silvey Tree Saver and Little Feller are the two current models of this type of jack.
Single Ram Units - The single ram unit is a self contained tree jack. The ram, pump, and oil reservoir are contained in one unit. One benefit of this compact design is there are no hoses to maintain or fittings to keep clean. Without hoses, this jack can operate at higher internal pressure and this high pressure is the secret to its super-lifting power. As a result, on a pound per pound comparison, the single ram unit is the most powerful jack on the market.
The Silvey Hi-Jacker is the current model of this type of jack.
All Silvey jacks have a pressure gauge. This allows the user to monitor the lifting force being applied to the tree and the internal pressure on the jack. This is important because if the jack's capacity is exceed, a safety bleed-down valve will open reducing hydraulic pressure and the jack's lifting force.
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This big tree is being cut by Sea Forest Enterprises on a job site in California. It is being lifted by three Treesaver rams. The combined force of the rams is 194 tons. In addition to high lifting forces, using more than one ram helps spread the force over a larger area. |
Our Advice
Today, the self-contained Hi-Jacker is out best selling jack. Most
fallers find it is ideal for working in smaller trees. It
offers plenty of lift in most second growth trees, yet its all-in-one
design makes it light, compact, and easy-to-carry. It is also less
expensive than the pack style jack sets, too. We still sell a
few Silvey
Tree Savers. Its big rams have the
most lifting capacity and it lifts higher than other jacks. These
are key features when jacking big wood.
For prices and more information, please call us.