Major structural failure on L4610 - ouch !!
- Thread starter rbargeron
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slowzuki
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Re the new grand L's, if you look at the casting design, 3 point top link attachment, and the external lift cylinders, it is less likely to suffer a similar failure.
I suspect the change was made due to what we see in these pictures.
Ken
I suspect the change was made due to what we see in these pictures.
Ken
Bobm
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I’ve been silently observing the excellent banter pertaining to the unfortunate fellow who damaged his L-4610 while using a three point mounted logging winch. Having horsed around with Farmi’s, Norse, Igland, and other 3PH logging winches for the past 25+ years, I offer a few pointers for those who turn their utility tractors into junior skidders.
When the 3PH winch is in use (ie. tractor stationery, winch lowered onto ground, and drum under PTO power), forces transmitted to the tractor are minimal. In essence, the tractor sits there providing power. The tractor might get jerked around a bit, but the forces transmitted to the tractor are rather uniformly distributed over the three hitch points. The top link still takes a bit more force than the lower links though.
During actual winch use, the top pulley may be the best pulley choice (versus using lower pulley) as the higher the pull point, the greater the tendency for the winch to “dig itself in” via downward forces. The more the winch digs itself into the soil, the less force is transmitted to the tractor. At any rate, as I said initially, in actual “tractor stationery” winch use, the tractor plays a minimal role. Demonstrating this point well is the fact that some will use very large 3PH winches on very small tractors, but simply use that winch/tractor combo in a stationery position as a “bunching” tool (loggers call them “yarders”)… the tractor/winch never actually skids the loads… instead a much larger tractor, pro log skidder, or forwarder subsequently picks up the logs at the yarder gathering point, and then skids those logs to a final landing. Make sense? In this set up you can skid a lot of material within the radius of the cable length, and do so with little rolling stock investment.
However, things change dramatically when one lifts a three point logging winch, with log attached, thus lifting 50+% of the log’s weight plus the winch weight. As Dick Bargeron clearly pointed out, the top link will then approach a severe acute angle on most logging winches when that winch is fully raised. Basic vector analysis will soon betray that if one skids (winch raised, PTO off, log on, tractor moving) using the top pulley, tremendous force can be transmitted to the top link (at an inordinate angle no less), while the bottom links don’t proportionately share the load. If one combines that scenario with a likely dip or two in the road (ala the L-4610 event), sudden and greatly increased forces can be sent to that top link.
Anyone who has ever purchased a new Scandinavian 3 point logging winch will note that the instruction/safety manual that came with the winch clearly states to NEVER SKID (tractor in motion) WITH THE CABLE RUNNING SOLELY FROM THE TOP PULLEY. That is a pretty clear statement. Yep, I know lots of you guys do (I’m guilty too!)… but we all must recognize why that bottom pulley is present. I’m confident there are many good reasons (other than destroying your prized Kubota!) to religiously use the bottom pulley when skidding – here’s at least a few:
1.) Find yourself “steering” using separate brake pedals? (‘cause your front wheels are no longer on the ground!!)… Duh! Lower the pull point! Use the bottom pulley, and even consider lowering the entire winch via pin position and/or hydraulic position lever.
2.) Think about this one: If you pull from the top pulley, and the log is down on bash plate, you probably have about 10” – 30” of cable showing between that top pulley and the hook at the cable’s end. If that hook ever broke, came unattached from choker, or cable broke near the hook, the cable may react by coming up, over the winch and ROPS, and potentially onto the top of your head. Hardhats and fiberglass sunshades are not designed to endure this trick.
3.) Value your tractor? If you pull from the top point, and turn rather sharply, the log can easily slid to the side of the winch, and actually come forward to redesign your tractor taillights and/or fenders. Ask virtually anyone who has owned a 3PH for a long time (and skids from top pulley) – he’ll probably talk about the high price of taillight lenses and/or fender sheet metal.
4.) On larger 3PH winches, if you use the top pulley, you may be able to lift a log high enough to come above the “bash plate” section of your winch. As a log will not held securely to the top pulley, (remember the exposed cable length in #2?) the log can repeatedly ram the winch body. While most good winches can take this log bashing, a truly big log can bend the thick steel plate of even the best winch.
5.) Even large tractors with skidding winches will occasionally complain loudly that one is exceeding the 3PH hydraulic lift capacity. What is likely happening is that due to the cable pull point, length of exposed cable, log weight/length, and uneven terrain, the winch is binding as it is literally trying to lift too large a percentage of the log. It’s akin to a fulcrum (winch) with a long lever (log) … only the lever portion is short (less than a foot), but is connected to the rest of the log that may be tree length. Just can’t do it!! Lesson to be gleaned: Listen to your hydraulics ALWAYS. If you have a loader, watch your bypass hose. If the whole affair is groaning, bypass hose stiff as oak, then comply and reduce the lift height. Personally, I think this scenario could have contributed to the L-4610 trauma.
In short, the “bash plate” section of a three point winch is there for a reason. Ideally, one should winch straight back from the tractor using the top pulley. Be aware of the tractor’s front wheels at all times… if the tractor rears up like Silver hearing the Lone Ranger’s whistle, consider using the lower pulley even when the tractor is stationery. Once the log is close to the tractor, run the cable through the lower pulley, and then S-L-O-W-L-Y bring the log close to the bottom pulley and set the cable brake. DO NOT cinch the cable hook/cable clamps real close to any pulley as that situation can introduce tremendous forces when skidding over uneven terrain. Lastly, lift the winch high, so that the bash plate portion of the winch approaches a horizontal plane and allows the log bottom to ultimately contact the nearly horizontal bash plate. In this manner a portion of the log weight is transferred to the bash plate, reducing cable stress, and simultaneously lowering the tractor pull point. Never use a 3PH winch without a loader or equivalent front weights.
When the 3PH winch is in use (ie. tractor stationery, winch lowered onto ground, and drum under PTO power), forces transmitted to the tractor are minimal. In essence, the tractor sits there providing power. The tractor might get jerked around a bit, but the forces transmitted to the tractor are rather uniformly distributed over the three hitch points. The top link still takes a bit more force than the lower links though.
During actual winch use, the top pulley may be the best pulley choice (versus using lower pulley) as the higher the pull point, the greater the tendency for the winch to “dig itself in” via downward forces. The more the winch digs itself into the soil, the less force is transmitted to the tractor. At any rate, as I said initially, in actual “tractor stationery” winch use, the tractor plays a minimal role. Demonstrating this point well is the fact that some will use very large 3PH winches on very small tractors, but simply use that winch/tractor combo in a stationery position as a “bunching” tool (loggers call them “yarders”)… the tractor/winch never actually skids the loads… instead a much larger tractor, pro log skidder, or forwarder subsequently picks up the logs at the yarder gathering point, and then skids those logs to a final landing. Make sense? In this set up you can skid a lot of material within the radius of the cable length, and do so with little rolling stock investment.
However, things change dramatically when one lifts a three point logging winch, with log attached, thus lifting 50+% of the log’s weight plus the winch weight. As Dick Bargeron clearly pointed out, the top link will then approach a severe acute angle on most logging winches when that winch is fully raised. Basic vector analysis will soon betray that if one skids (winch raised, PTO off, log on, tractor moving) using the top pulley, tremendous force can be transmitted to the top link (at an inordinate angle no less), while the bottom links don’t proportionately share the load. If one combines that scenario with a likely dip or two in the road (ala the L-4610 event), sudden and greatly increased forces can be sent to that top link.
Anyone who has ever purchased a new Scandinavian 3 point logging winch will note that the instruction/safety manual that came with the winch clearly states to NEVER SKID (tractor in motion) WITH THE CABLE RUNNING SOLELY FROM THE TOP PULLEY. That is a pretty clear statement. Yep, I know lots of you guys do (I’m guilty too!)… but we all must recognize why that bottom pulley is present. I’m confident there are many good reasons (other than destroying your prized Kubota!) to religiously use the bottom pulley when skidding – here’s at least a few:
1.) Find yourself “steering” using separate brake pedals? (‘cause your front wheels are no longer on the ground!!)… Duh! Lower the pull point! Use the bottom pulley, and even consider lowering the entire winch via pin position and/or hydraulic position lever.
2.) Think about this one: If you pull from the top pulley, and the log is down on bash plate, you probably have about 10” – 30” of cable showing between that top pulley and the hook at the cable’s end. If that hook ever broke, came unattached from choker, or cable broke near the hook, the cable may react by coming up, over the winch and ROPS, and potentially onto the top of your head. Hardhats and fiberglass sunshades are not designed to endure this trick.
3.) Value your tractor? If you pull from the top point, and turn rather sharply, the log can easily slid to the side of the winch, and actually come forward to redesign your tractor taillights and/or fenders. Ask virtually anyone who has owned a 3PH for a long time (and skids from top pulley) – he’ll probably talk about the high price of taillight lenses and/or fender sheet metal.
4.) On larger 3PH winches, if you use the top pulley, you may be able to lift a log high enough to come above the “bash plate” section of your winch. As a log will not held securely to the top pulley, (remember the exposed cable length in #2?) the log can repeatedly ram the winch body. While most good winches can take this log bashing, a truly big log can bend the thick steel plate of even the best winch.
5.) Even large tractors with skidding winches will occasionally complain loudly that one is exceeding the 3PH hydraulic lift capacity. What is likely happening is that due to the cable pull point, length of exposed cable, log weight/length, and uneven terrain, the winch is binding as it is literally trying to lift too large a percentage of the log. It’s akin to a fulcrum (winch) with a long lever (log) … only the lever portion is short (less than a foot), but is connected to the rest of the log that may be tree length. Just can’t do it!! Lesson to be gleaned: Listen to your hydraulics ALWAYS. If you have a loader, watch your bypass hose. If the whole affair is groaning, bypass hose stiff as oak, then comply and reduce the lift height. Personally, I think this scenario could have contributed to the L-4610 trauma.
In short, the “bash plate” section of a three point winch is there for a reason. Ideally, one should winch straight back from the tractor using the top pulley. Be aware of the tractor’s front wheels at all times… if the tractor rears up like Silver hearing the Lone Ranger’s whistle, consider using the lower pulley even when the tractor is stationery. Once the log is close to the tractor, run the cable through the lower pulley, and then S-L-O-W-L-Y bring the log close to the bottom pulley and set the cable brake. DO NOT cinch the cable hook/cable clamps real close to any pulley as that situation can introduce tremendous forces when skidding over uneven terrain. Lastly, lift the winch high, so that the bash plate portion of the winch approaches a horizontal plane and allows the log bottom to ultimately contact the nearly horizontal bash plate. In this manner a portion of the log weight is transferred to the bash plate, reducing cable stress, and simultaneously lowering the tractor pull point. Never use a 3PH winch without a loader or equivalent front weights.
Cliff_Johns
Elite Member
What a terrific treatise! Thanks for putting the thought and time into it and posting.
Cliff
Cliff
grandad
Platinum Member
Thanks for a great explanation! You may have only hooked on (no pun intended) to TBN recently, but you obviously know plenty about those logging winches. Welcome!
Poppa
Gold Member
Grandad, take a look at BobM's Reg date. He is member number 25. Not sure the title "New Member" really applies here.
That was a great explanation Bob and thank you.
Mike
That was a great explanation Bob and thank you.
Mike
DAP
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Bob ... that was a nice offering. Here's an even more important question.
What was your FIRST post, this being your 2nd as member #25?
/forums/images/graemlins/grin.gif
What was your FIRST post, this being your 2nd as member #25?
/forums/images/graemlins/grin.gif
Bobm
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You're welcome to all!
Doug. actually I have posted many times more than twice. I used to contribute regularly - most of my ranting pertained to chippers, 3PH winches and related woods stuff.
However, when TBN changed format sometime ago, I lost access to my newer name (Tree Guy Bob), and resorted to using my original user name which dated back to the toddler days of TBN.
Doug. actually I have posted many times more than twice. I used to contribute regularly - most of my ranting pertained to chippers, 3PH winches and related woods stuff.
However, when TBN changed format sometime ago, I lost access to my newer name (Tree Guy Bob), and resorted to using my original user name which dated back to the toddler days of TBN.
grandad
Platinum Member
If that qualifies as one of your "rants", I really want to see one of your more serious messages /forums/images/graemlins/laugh.gif /forums/images/graemlins/laugh.gif /forums/images/graemlins/laugh.gif
polecat
Platinum Member
THANK U SO MUCH !!!!!!!!...(TREE GUY BOB)!!!!!!! /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif
NOT ONLY for yer eloquence ...but 4 yer intelligence and true mastery of a subject that i hav ebin wrastlin with as to how to delicately put an end to this foolishness!!!......PLEASE do not git me wrong!!!!..we have seen no pic's on the cause of this whole entire string!!! jist the outcome!!!! and with my (limited in respects to yers) experience in this field someone wasn't tellin the !!!!!"REST OF THE STORY!!!!" accordin to MR. PAUL HARVEY!!!!...any one who uses a cut to pull must evaluate the amount of stress that he/she is puttin on ....thines one cut!!!!!....I HAVE TO PERSONALLY SAY THAT U DID NOT ONLY A SUPERLATIVE !!!! BUT A JOB !!!!!!
!!!!!!!!!!!!!!!!!EXTRAORDINAIRE!!!!!!!!!!!!!!!!!!!
And may it b said by me that u should git an " HONORARY VETERAN'S MEMBERSHIP""""..AS u lost the ability on yer first handle to do so!!!!!!! JUST SO U KNOW !!!!!! I WOULD GLADLY GIVE U ALL OF MY POST'S TO GO TOWARD'S THAT AND WILL GLADLY BE REVERTED BACK TO (WILL GLADLY TRADE WITH U )!!!!! A NEW MEMBER!~!!!!..JIST 2 keep someone as learned as yerself on board permanently!!!!
May we please c yer presence more often ......!!!!! /forums/images/graemlins/cool.gif /forums/images/graemlins/cool.gif
......................"TREE GUY BOB"..........!!!!!!!!!!!!!! /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif
/forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif
TODD HALL....from liddl ol maine!!! /forums/images/graemlins/cool.gif /forums/images/graemlins/cool.gif /forums/images/graemlins/wink.gif
NOT ONLY for yer eloquence ...but 4 yer intelligence and true mastery of a subject that i hav ebin wrastlin with as to how to delicately put an end to this foolishness!!!......PLEASE do not git me wrong!!!!..we have seen no pic's on the cause of this whole entire string!!! jist the outcome!!!! and with my (limited in respects to yers) experience in this field someone wasn't tellin the !!!!!"REST OF THE STORY!!!!" accordin to MR. PAUL HARVEY!!!!...any one who uses a cut to pull must evaluate the amount of stress that he/she is puttin on ....thines one cut!!!!!....I HAVE TO PERSONALLY SAY THAT U DID NOT ONLY A SUPERLATIVE !!!! BUT A JOB !!!!!!
!!!!!!!!!!!!!!!!!EXTRAORDINAIRE!!!!!!!!!!!!!!!!!!!
And may it b said by me that u should git an " HONORARY VETERAN'S MEMBERSHIP""""..AS u lost the ability on yer first handle to do so!!!!!!! JUST SO U KNOW !!!!!! I WOULD GLADLY GIVE U ALL OF MY POST'S TO GO TOWARD'S THAT AND WILL GLADLY BE REVERTED BACK TO (WILL GLADLY TRADE WITH U )!!!!! A NEW MEMBER!~!!!!..JIST 2 keep someone as learned as yerself on board permanently!!!!
May we please c yer presence more often ......!!!!! /forums/images/graemlins/cool.gif /forums/images/graemlins/cool.gif
......................"TREE GUY BOB"..........!!!!!!!!!!!!!! /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif
/forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif
TODD HALL....from liddl ol maine!!! /forums/images/graemlins/cool.gif /forums/images/graemlins/cool.gif /forums/images/graemlins/wink.gif