Looking at timberpro harvester/processor machines, ive noticed the 8x8s use a telescoping stick with linkage cylinder on the cab side while timberpro tracked machines use a fixed stick with conventional style cylinder underneath on the tree side of the boom.
I realize a tracked machine can simply zig zag around the site to get to wood and does not need the [more expensive to build] 3 stage stick that a less maneuverable 8x8 needs in order to reach out from its more defined pathway.
What i cant figure is why the telescoping stick places the cylinder on the back with linkages. I see that it can fold up flatter and crowd in toward the machine tight.. And a few other minor pros/cons i can think of. What is better about the linkage setup? If the linkaged stick is better why do the tracked machines not have a fixed stick with a cab mounted link cylinder? It would be cheaper to place the cylinder on the wood side of the boom with simple mounts even on a telescoping stick, so what feature or characteristic makes it worth the trouble and expense of building dog bones and H link?
Just trying to understand the logic in the design. What am i missing?
I guess an easier question is what are the merrits of a 'buncher crane' vs a 'forwarder crane' ?
(https://forestryforum.com/gallery/albums/userpics/43722/1603116801883.jpg?easyrotate_cache=1603116616)
(https://forestryforum.com/gallery/albums/userpics/43722/2338484_3787_159_0001.jpg?easyrotate_cache=1603116618)
(https://forestryforum.com/gallery/albums/userpics/43722/TL765D.jpg?easyrotate_cache=1603116620)
(https://forestryforum.com/gallery/albums/userpics/43722/1603116778868.jpg?easyrotate_cache=1603116632)
The pictures answer your question. Usually a dangle head weights less. A fixed head or hot saw more. As far as the linkage prentice used that on there loaders yrs ago and all the fowarder cranes use them
Lift , Buncher booms simply have more leverage.
Ahh youre right snowstorm i wasnt looking at what type of heads were on them at all.
Its obvious the telescoping stick is delicate compared to a solid buncher stick. But it would still be cheaper to put the cylinder in front rather than produce the wrist joints. Perhaps they are orienting them this way to limit how much cylinder force is available to destroy the stick at extension. Maybe the wrist is an engineered fuse.
Quote from: mike_belben on October 19, 2020, 11:49:24 AM
Ahh youre right snowstorm i wasnt looking at what type of heads were on them at all.
Its obvious the telescoping stick is delicate compared to a solid buncher stick. But it would still be cheaper to put the cylinder in front rather than produce the wrist joints. Perhaps they are orienting them this way to limit how much cylinder force is available to destroy the stick at extension. Maybe the wrist is an engineered fuse.
With the stick cylinder on the bottom you can lift out but you can't pull in as tight. With have a squirt with the parallel style boom you gain reach most of those squirt style are 32' some out here are 36' vs that 765/775 it would be 30 maybe 32 with the harvester/shovel boom.
The red tracked Timberpro has the live heel to help pull the machine around the slopes. The dangle bar saw head, to bunch and shovel with, does not chew the felled trees up as much as a continuous disc saw head might, when shovelling.
In steep terrain, the 'fixed' felling heads with linkage are supposed to offer more tree felling control than dangle saw heads and dangle processors, which in turn resulted in better aligned trees for grapple cable logging and less breakage so more volume of logs hauled up faster.
John Deere 959M with aus fixed felling head (pulpmate & rosin which has become the Quadco/ Southstar head), JD tethered with the t-mar winch machine.
Mountain Logging expand their family of green machines (https://hitachicm.com.au/solutions/forestry/john-deere-fleet-adept-to-mountain-logging)
The tracked machines can have the squirt booms too. (Scotland TC LH845 with dangle head processor)
T-WINCH 10.2 in Scotland | Drone Video - YouTube (https://youtu.be/B_FRtAJClAY?t=17)