Wraps on Port a Wrap

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sal b

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in this pic would that be considerd 3 1/2 wraps or 2 1/2. one guy at work says its one thing and another guy says something different.:dizzy:
 
three wraps.....1/2 wraps come off the top post as stated.....Definitely too many to let most pieces run....I rarely tell the guys to take more than two wraps...
 
I use 1 wrap for loads under 500 lbs , 2 wraps over 500lbs and the only time when I have used 3.5 wraps is when the piece was well over 1000-2000 pounds . I have seen ropes break because there were too many wraps , not allowing a little bit of run needed to overcome the initial shock load
 
I would call that 3 wraps. As Dan just pointed out there is an extra bit of contact constituting about 1/4 circle but that is "normal". The way the rope needs to be threaded we always wind up with a bit extra on the initial wrap.
 
I would call that 3 wraps, I don't count the entrance rope going up the tree, or the exit tail coming off the tube. I would only count the actual rope that is on the tube as being part on the friction device and I see 3 wraps.
Of course, it could be on the metric system and then it would be completely different. :)
 
Some might say 2 wraps and some might say 3. Who really cares. It all comes down to experience. If you are working the porta-wrap and you look up at the piece your buddy is going to cut, you should know how many wraps to take so that you can handle the weight. It is what ever you feel is right and safe.....
 
agreed

Dadatwins said:
I would call that 3 wraps, I don't count the entrance rope going up the tree, or the exit tail coming off the tube. I would only count the actual rope that is on the tube as being part on the friction device and I see 3 wraps.
Of course, it could be on the metric system and then it would be completely different. :)
i will not count the entrance as a wrap either
 
Double RoundTurn; 3 wraps. Then plus that final bend as a seperate consideration.

Noting if the pull direction on tail was up; i'd 'rate it' 3.5. But here, i take the change in direction as breaking off to another mechanic type; to be recognized and accounted for seperately. Similarly, i take a RoundTurn (2) as 4x or so better than a Turn(1). i think of a Turn as some friction, some slip; but a RoundTurn more as an empowered stop/ lots less-Zer0 slip. Hence, i think of a RoundTurn as worth 3 Turns. i think of 4 turns as a 'Coil', to make our friction hitches; then a single Turn mechanic maid separately as a some slip/some grip mechanic to precede the coil. So, the preceding Turn/Hitch of Distel etc. is separate mechanically from the 4 Turn coil/ does a separate job/ is not a continuation of the Coil.

You really have to watch this power mechanics i think, because at high loads especially, simple changes make pivotal changes in the mechanics. Like, a CrossedTurn pulled 1 way slips, with the Standing Pull under the Bitters. But the same exact lacing pulled the other way, so that the Standing Pull on top of the Bitters; is a Hitch formation and can seize.

Lots of stopping power none the less, mebbe too much for a lot of things; without allowing some run or elasticity to re-lease 'steam' from suddenly high loaded system. We have the pressure X surface area contact; but then for every real complete choke around (a good choke being really more than a Turn); we get this gripping choke folding back into itself for awesome grip power that a Turn just ain't got! Of course; i think that the real power in anything is capturing the equal and opposite forces to fold back on itself (so it runs towards the work along with your efforts and not running away from work!) back into the work!
 
TheTreeSpyder said:
Double RoundTurn; 3 wraps. Then plus that final bend as a seperate consideration.

Noting if the pull direction on tail was up; i'd 'rate it' 3.5. But here, i take the change in direction as breaking off to another mechanic type; to be recognized and accounted for seperately. Similarly, i take a RoundTurn (2) as 4x or so better than a Turn(1). i think of a Turn as some friction, some slip; but a RoundTurn more as an empowered stop/ lots less-Zer0 slip. Hence, i think of a RoundTurn as worth 3 Turns. i think of 4 turns as a 'Coil', to make our friction hitches; then a single Turn mechanic maid separately as a some slip/some grip mechanic to precede the coil. So, the preceding Turn/Hitch of Distel etc. is separate mechanically from the 4 Turn coil/ does a separate job/ is not a continuation of the Coil.

You really have to watch this power mechanics i think, because at high loads especially, simple changes make pivotal changes in the mechanics. Like, a CrossedTurn pulled 1 way slips, with the Standing Pull under the Bitters. But the same exact lacing pulled the other way, so that the Standing Pull on top of the Bitters; is a Hitch formation and can seize.

Lots of stopping power none the less, mebbe too much for a lot of things; without allowing some run or elasticity to re-lease 'steam' from suddenly high loaded system. We have the pressure X surface area contact; but then for every real complete choke around (a good choke being really more than a Turn); we get this gripping choke folding back into itself for awesome grip power that a Turn just ain't got! Of course; i think that the real power in anything is capturing the equal and opposite forces to fold back on itself (so it runs towards the work along with your efforts and not running away from work!) back into the work!
ah ok
 
As far as frictional surface contact perhaps 3.25 - 3.5; but as far as the extra friction force obtained from a choke collar pressing towards itself mercilessly; to increase friction beyond just the surface contact numbers; perhaps not...

i think direction as a force is overlooked a lot. This elemeant is very important in considerations. A few degrees off can make something balanced, into leveraged etc.

Force is the only thing that can overcome distance; but must always have direction; or it doesn't exist. For, if the force doesn't seek to pull, push (or twist) in a specific direction; the force doesn't exist/ there is no pressure/ no force.

A Distel maid with a Double Round Turn(3) on top; and not a Coil (4), then followed by the hitch under the Double Round Turn; is not the same as just a Coil with no hitch under; even though the same amount of turns. i see the hitch under as a separate mechanic/consideration.

In the Porty example, i see the Double Round Turn(3); then the extra bend and friction as separate mechanic. Like i said the frictional contact surface may be the same; but not the force on the line increasing the friction by another 'choke ring' because of the change of direction breaking ranks.

Similarly, a single turn pulling up would place a pull on Porty of 2x - friction. But pulled to the side as shown (with only single turn) might give same friction contact surface area, but not same pull up force on Porty; because of the change in direction. In a Round Turn etc.; the extra force of the proper direction can increase the friction power (i think) by increasing the force into the friction multiplier; as the first turn pulls up, and the second 'catches' that and presses back for the choke. Ignoring friction for a second; The single turn would pull up at 2x; the round would press back down 2x towards the previous 2x; to give this choke of 4x. Then add friction in, the choke 4x would increase the friction relevancy beyond just simple contact.

Orrrrrrrrrr something like that.......i think!
:taped: (We are now returning to normal programming)
 
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mini portie

TreeCo said:
But the direction of pull on the tail is not up! It's horizontal.

It makes almost exactly 3.25 turns.

The Port-a-wrap is a great tool. I've got two of them. Aside from a great friction device.....I like the way it can be locked off so easily.

Dan
didya try the mini portie yet accepts a halfinch line
 
That is clearly two wraps. That about all you need. Stand in close. The farther away the less control you have on letting things fly when you need to. Sure if something breaks your right there but what the F thats what those ground guys get paid for. I haven't killed one yet.
 

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