Rigging Physics 101 -- Redirect Pulley

[SeanKroll]

There's a place for everything.

As long as you don't run your clutch, stranding you vehicle where it is, you're golden.

There is that problem of a learning curve.

I've had an employee be more than willing to use my clutch to learn.


The guy I mentioned, glazed his clutch down a steep, waterfront driveway. Slipped too much to get up the driveway. Expensive tow-bill on top of $3k for the clutch replacement. I have a hard time driving out of a lot of those driveways. I bet he blocked the lake-loop road a good while, not good publicity.

Having the skilled, experienced operators to do things well, makes all the difference.



Some gypo pulled a big old cottonwood for State Parks with his little Toyota, by chaining the frame to a tree, and using the winch. He knew what was solid, and what he could do (wedging, too, at least as a backup, if not obvious).

Similarly, when we had hard pulls, we butted a skidder tire into a tree, or chained the skidder in place. At least, without chains, the skidder winch would skid the skidder if not secured, and the tree/ lean was big enough.

 

[rfwoody]

Robert, in my experience, your truck (assuming top operating condition) is an excellent tool for the job. I drove one just like it for 7 years, over 80k miles, 80% on backwoods logging roads. A USFS rig.

As for the question of Warn vs. Harbor Freight. I have no experience with the latter. They may be wonderful...or for all I know, crap. There are other manufacturers out there too. But again, I have extensive experience with 3 different Warn models, and no other. To be clear, I am definitely prejudiced, but with no decent standing for comparisons.

But I do see the prices. A 12k Warn will run you about 400-500 dollars more than a 12k Badland (Harbor Freight). I'd spend that pissant bit of money more in the drop of a hat, for a tool I KNOW will work hard, and for a very long time. I'd go with Warn, myself.

Now if you can get positive feedback from real people with real experience with the Badland models, I say go with that info...I just don't know anyone among my friends and fellow woods workers who has gone that route.

Thanks and Thanks Mr. Burnham. That makes great sense.

 

[rfwoody]

Thanks Sean and all!

Johnny, I guess I would start with a Bowline.... for that reason that it can be untied after heavy loading.... it seems there were some other discussions about best way to tie a rope to a hitch, etc.(?)

But I am a little concerned about the loss of strength of a Bowline ..... however it has been said by some (?) that most of the time the rope breaks at some place other than the knot?

Hadn't thought about a gas winch...

Stumpshot -- why a double bowline instead of a bowline? ..... is your entire rope doubled? Thanks.

 

[treesmith]

I favor a Munter hitch (with 3-4 half hitches), as I often tension by hand as I'm tying off, and it always unties easily.

 

[rfwoody]

Thanks Treesmith. I need to research and try the Munter hitch

 

[SeanKroll]

But I am a little concerned about the loss of strength of a Bowline ..... however it has been said by some (?) that most of the time the rope breaks at...

Negative rigging is often done on a running bowline, or marl or half-hitch preceding the RB.


Be most concerned about cutting without certainty, or doing things when confused by the situation or frustrated.

 

[Mick!]

Agree with Sean, don’t worry about snapping a rope through the wrong knot.

 

[rfwoody]

thanks Sean and Mick .... very much appreciate you sharing your knowledge and experience.

 

[stig]

Unless it is a Dyneema rope.

 

[theTreeSpyder]

Winch will still only be as good as it's anchor/truck etc.
Crane is only good as ground it stands on!!
.
You can pull and not burn up clutch so much by just using pull in it's power band, not screeching redline.
To impact something can also run 15-20mph with clutch pushed in etc. when hit rope tension with weight of truck x speed

i think of frame as truck, that rides on 2 axle spindles, all rope pull force goes to frame,
>>i don't route that force to ball, THRU BUMPER to frame,but rather direct to frame.
>>pulling thru un-re-enforced bumper is back to pulling the Clock Hitch tightened to tree scenario of pulling like wrench across, but wanting support
>>half load force traces thru each half of bumper from ball to frame and acts as wrenches trying to bend bumper
** The 'Arch' in Architecture is literally meant for no such flat pulls(or pushes) across lengths for support!! **
** Across a device pulls/pushes are for wrenching to turn or bend, to deform or break, NOT support!! **
.
i've often wondered if you(rfWoody) remove refuse off site?
>>if not i wouldn't lift an MF'ing thang, drag all to burn pile etc. after minimal cutting.
Truck as a mule can be best friend! Might even clean it (i never did)
.
i'm big advocate about re-direct pulley betwixt truck and upward line so as pull forward don't pull back and UP on truck reducing traction just when needed!!
>>weight in back of truck on good ground, tires,with gas, working fuel gauge etc.
A Shawn notes try to grab low on tree, even preferable if tree leans away from pull.
.
Something to chew on, not necessarily use, but absorb.
i always say numbers in ABoK aren't knot numbers, but lesson numbers of forces. Present knot is just example.
Racing thru ABoK to see how many knots can tie is destination goal, but real knowledge is in journey of how works etc.so can carry to other things.

Clean, simple,caveman basics can give clues to many things as minimal required framework
Basic Army Rigging Manual.pdf
.
i favor carrying fight directly to frame, NOT FROM BALL THRU BUMPER TO FRAME.
(If in electrical imagery sense another slanted BEAM goes from ball to frame to carry force flow is generally ok, but not thru bumper as only 'electrical' force path from ball to frame).
.

Bowline is good,but as purist find it deforms Standing Part much more, same as Sheet Bend, Bell ringer Sheep Shank all have same 360 deformity to Standing Part.
.
Usually can find friendly hole on bumper for screw link.
>>i consider a screw link as a dual leg support device like link or clevis
>>as opposed to a single leg support device like hook,i classify a carabineer as single leg support
>>with good 'mousing' for more strength and security, but totally different than 2 solid legs of support as a device.

.
Knot strength is TOTALLY to Standing Part as most intense loaded part before frictions
>>then just like metal or wood where most loaded part deforms most is weakest link in chain that thereby dictates strength.
Most PURE INLINE /least deformities wins every time as capacity of line, all else is degradation (unless add another leg of support) against potential strength.



Reverse view to see better thru this maze(well maybe eventually): if wanted speed or distance increase, would take power decrease.
>>In original pic would take red arrow and tie back to anchor tree, leaving bight towards truck pull
>>put pulley in bight and mount to truck
>>1 leg of pull dead ends to anchor tree and is 'wasted' other goes to target tree when truck pulls
>>so half pull to target, as other half is to anchor,but pulling 2 legs with truck and target with 1 leg
>>this will make faster pull 2xSpeed, 1/2 as strong.
>>simply reverse strategy of putting 2 legs of pulley pull against target to divide the load for 1/2 Speed 2x as strong
Pulley on output against target is 2xPower, but inverse if pulley on input against efforts
3 possible pulley positions:
>>Pulley on load output, gives 2 legs of pull against for more power
>>Pulley on effort input have to pull 2 legs to get one movement, so pulls faster but weaker
>>Pulley on non-moving part\anchor is 1:1 breakeven point, but change in direction

 

[Stumpshot]

<1 word response

 

[Tree09]

Just make sure to get locates before pounding in any anchors!

 

[CurSedVoyce]

Amen...

 

[Burnham]

tru dat.

 

[Bermy]

We call those 'picket holdfasts', WE use them for making an anchor for our rooftop system for storm damage work in the SES. They work well.
Ha, read the small print, you call them the same thing...

 

[Marc-Antoine]

How tall they are and how deep they have to be pounded to get the numbers showed in Kenny's pic?

 

[DMc]

The number of pounds that the first stake can hold will always be variable and dependent on site conditions. It is just understanding the multipliers that the technic provides that is important.

 

[Marc-Antoine]

OK, thanks to point that.

 

[rfwoody]

Unless it is a Dyneema rope.

Thanks for the clarification, Stig

 

[rfwoody]

Kenny, that makes 2 info packed posts of yours I'm going to have to come back to to try to digest.
Thanks a lot for taking the time to share your detailed knowledge.

ha, bought a hard copy of that very Army manual (it is a large version... not the little WWII smaller size manuals) a while back off Amazon... probably after I saw you, or somebody reference it .... and was looking at that very page(s) a few nights ago.


Kyle, what are "locates" .... call utility company(s) for any underground conduits, etc.? thx.

Bermy, it seems that's what the manual called them too.... I think that is in the Boy Scout -- the original Boy Scouts -- manual.

Thanks Marc, DMc for additional clarifications.

 

[theTreeSpyder]

That small manual is chock full of using minimal tools, in most basic concepts.
>>many scenarios are these basic skeletons with more fluff of this or that skin make-over; but all the same underneath if you squint right.
i've never done the pickets per se, but have assessed many things by that concept, and built some towards, but never exactly as Bermy lends.
.
i got a different army code manual( i think about keeping footlocker tidy) @Christmas with GI Joe (as we were all being preened for either college or 'Nam in a time when every voting age male seemed to disappear at 18 to these paths),then a decade later found this small manual in library(that i pedaled 1 way 5 miles to very often, on a good day continue another 5 to Grandma's before turning ship around) as a teen. Always liked knots and such!
.
Still needs some work,but might try this medium again:
<iframe width="560" height="315" src="//www.youtube.com/embed/jw5PiCKJr_s" frameborder="0" allowfullscreen></iframe>

 

[Tree09]

Yup. There's a ton of stuff buried where you least expect it, and it's illegal to even stick a shovel in the ground without calling 811, and giving them 2 business days to come and mark everything. It's free of course. You wouldn't believe the stories I've heard, entire families dying over stupid stuff.

 

[rfwoody]

wow. Thanks Kyle.

Kenny, thanks for the time and detail.

(ha, my introduction to army manuals was from my next door neighbor friend growing up -- his dad's -- WWII manual "Combat Training of the Individual Soldier and Patrolling" -- it was part of our inspiration for playing and clubs based on Combat, Man from U.N.C.L.E, Wild Wild West, etc. .... but I digress...)

i think of frame as truck, that rides on 2 axle spindles, all rope pull force goes to frame,
>>i don't route that force to ball, THRU BUMPER to frame,but rather direct to frame.
>>pulling thru un-re-enforced bumper is back to pulling the Clock Hitch tightened to tree scenario of pulling like wrench across, but wanting support
>>half load force traces thru each half of bumper from ball to frame and acts as wrenches trying to bend bumper
** The 'Arch' in Architecture is literally meant for no such flat pulls(or pushes) across lengths for support!! **
** Across a device pulls/pushes are for wrenching to turn or bend, to deform or break, NOT support!! **

If in electrical imagery sense another slanted BEAM goes from ball to frame to carry force flow is generally ok

IF my truck's hitch is somehow attached directly to the frame (vs. attached to the bumper)
-- then would that eliminate the need to attach the screw link directly to the frame for pulling?

i've often wondered if you(rfWoody) remove refuse off site?
>>if not i wouldn't lift an MF'ing thang, drag all to burn pile etc. after minimal cutting.

Usually -- but thankfully not on this job... so far (another story)
.... just drug all brush to burn pile and cut wood into ~20" lengths and more or less left in place.

Truck as a mule can be best friend!...

good point... if yard isn't too wet/muddy

....i always say numbers in [Ashley Book of Knots] aren't knot numbers, but lesson numbers of forces [expansion and emphasis mine]......

..."lesson numbers of forces"(??)............What means this, please? thx.

also... please, what do you call that knot in your illustration?

>>Pulley on load output, gives 2 legs of pull against for more power
>>Pulley on effort input have to pull 2 legs to get one movement, so pulls faster but weaker
>>Pulley on non-moving part\anchor is 1:1 breakeven point, but change in direction

What about this, Kenny (and/or Anyone)? .... and does this go along with what you were suggesting, earlier, above (pulley on load)? ........ did I calculate my forces correctly?



thanks!

 

[Bermy]

Something doesn't look right...but I gotta go to town, someone else will pipe up I'm sure.

 

[rfwoody]

Thanks Bermy .... much appreciate your experienced "gut" on this!