If 5/8" line enough is 3/4" really better

[rfwoodvt]

If 5/8\" line enough is 3/4\" really better

Hey Folks!

We're getting ready to re-tool and replace our Bull ropes.

Most of our work pieces are 700 pounds or less and we have been using 1/2" and 5/8" successfully. So far using these sizes we have been able to maintain better than a 10:1 static SWL ratio.

Right now we are debating whether we should elimiate the 1/2 rigging ropes and use 5/8 and 3/4.

We've already listed pros and cons but we're interested in hearing what you folks think just in case we've missed something.

Any help you can offer would be appreciated!

 

[TheTreeSpyder]

Re: If 5/8\" line enough is 3/4\" really better

Well, without shockloading 10k Arbor-Plex/Plus 5/8" should be enough i would think; let alone going to doublebraid polyester 5/8" in the 14-16k range. Also, 5/8 fits more stuff and is lighter than 3/4".

What are forensic wear patterns on yur rigging lines? Burnt, busted, cut, worn etc.? Compare ages, uses, strengths. i try to wear out 1/2"; and save back wear/loss exposure on 5/8".

Jest my view....

 

[Axman]

Re: If 5/8\" line enough is 3/4\" really better

We recently retired our 5/8 Arbor Plex bull rope this spring.

I replaced it with 1/2 in. Blue Stable Braid. Has more tensile than the Arbor Plex. It doesn't seem to hold a bowline as good as Arbor Plex. Till it got broke in we were putting a stopper on the tail just for some security.

I also picked up a 5/8 Red Stable Braid for those special occasion large nasty removals that nobody else wants.

I would think these two size ropes would cover most any removal unless you are doing some really King Kong size trees.

If you change to 3/4 rope do you have 3/4 in pulleys to go with it. This is the main reason for our recent selection for bull ropes. We only have one 3/4 in sling block.

Couldn't justify more pulleys for one rope.

We'll just make two cuts instead of one if need be.

Ax-man

 

[tod_k]

Re: If 5/8\" line enough is 3/4\" really better

I carry 1/2", 9/16" ( my favorite) and 5/8" stable braid. The 1/2" is stronger than 5/8" arborplex. I hate dragging rope around that I do not need.

 

[klimbinfool]

Re: If 5/8\" line enough is 3/4\" really better

Half inch lines are very handy in my opinion. I use them a lot . Although, there are getting hard to find in the double-braid material.If alls you are doing is take downs , then yes 5/8 would probably be more suitable to buy. If you prunning and have to rope out an occassional limb, why use a 5/8 or 9/16 rope. 90% of my rigging is done with a 1/2 inch line, mainly because I trust my crew running the line .

If a 5/8 line such as stable braid, is comparable in weight rating to lets say 3/4 inch arbor plex then I would use Aborplex for the take downs . Especially if you know you are going to be doing heavy shock loading the line. The 3/4 aborplex will have more absorbtion strength then the 5/8.Not that I use aborplex , but just as an example .

Greg

 

[treeclimber165]

Re: If 5/8\" line enough is 3/4\" really better

Do a lot of people actually buy special 1/2" ropes for basic roping? I have always used 1/2" arbo rope, sometimes a replaced lifeline, sometimes bought specifically for roping. I've never met anyone who owned or used 1/2" double braid. I could not see the reason for not using the same type rope we climb on.

When buying a new lifeline, I tend to consider its servicability as a lowering line in the second half of its useful life. I try to get different colors so my lifeline and lowering line are never the same color.

I agree with above statements on the 5/8" double braid over the 3/4" ArborPlex. 5/8" rope will run in a 3/4" block but 3/4" rope will not work in a 5/8" pulley. For heavy roping buy the double braid and lots of rigging toys. I spliced an eye in mine and use a 63kN steel rigging pulley instead of tying knots. Double braid is easy to splice.

 

[Mahk_Adams]

Re: If 5/8\" line enough is 3/4\" really better

Rick;

What do you mean by "...a 10:1 static SWL ratio"?

What is the dynamic load that is imparted to the line? It seems that the dynamic load is more important because that will be higher than the static load.

Mahk

 

[NickfromWI]

Re: If 5/8\" line enough is 3/4\" really better

posted by treeclimber165...

"When buying a new lifeline, I tend to consider its servicability as a lowering line in the second half of its useful life. I try to get different colors so my lifeline and lowering line are never the same color."

This doesn't seem to make sense. I rope that you no longer trust to hold your less than 200lb self, you now drop logs on? If a life line is done, I see it as done. And as far as the half inch double braid, simply for the fact that the double braid is usually stronger than climbing line, that makes it more useful for rigging purposes. And, I like the feel of double braid going through a pulley and portawrap.

Regarding the original question of the thread, I think you answered the question yourself when you said that 5/8th is enough. The 3/4 is just extra weight unless you're actually gonna use it. I personally like a 9/16th (Yale Double Esterlon splices nice). Extra strength over 1/2 inch, and the weight difference is only slightly noticable.

love
nick

 

[treeclimber165]

Re: If 5/8\" line enough is 3/4\" really better

</font><blockquote><font class="small">In reply to:</font><hr />
This doesn't seem to make sense. I rope that you no longer trust to hold your less than 200lb self, you now drop logs on? If a life line is done, I see it as done.

[/ QUOTE ] As discussed a hundred times before, my lifelines get delegated for roping duty when the old lowering line gets retired. My current lowering line only saw duty as a lifeline for about 2 months. I never once claimed or implied that I would ever consider using worn out, unsafe ropes for rigging. You are a pain. F.U.

 

[Mike_Maas]

Re: If 5/8\" line enough is 3/4\" really better

Nick, you are questioning a guy who has never used a rope larger than 1/2", much less a double braid rope.
Why he even posts on a thread like this is wierd.
Using an old climbing line for a bull rope...hehehe...what a dork. I can hear him in court, "Your honor, I know'd it ain't right...but I saved durned near 100 dollars U.S., almost every year, using them cheap old used ropes."

 

[joe]

Re: If 5/8\" line enough is 3/4\" really better

Hi, Rick;

I think you're like many of us and read industry material. Reread Don Blair's book, Arborist Equipment. You'll notice he recommends a line such as double braid for tasks that require little drop of a load due to the line stretching. A line which stretches, even though the line may be weaker, will be a better choice for general tree work since these lines will absorb energy by stretching more than double braids.

If you're estimating your loads to be 700 lbf, I'd go with the 3/4" line since you're not seeing motion as part of your load. Double braid rope is good stuff,
but it's better to think in terms of how the line will be used that you need a line which stretches little. Arborist Equipment discusses this issue.

Joe

 

[TheTreeSpyder]

Re: If 5/8\" line enough is 3/4\" really better

I try not to shockload at all; even using slow hinging/hand off to rigging line to pretension the line automatically to the load before tearoff. i look at putting 3-500# max per leg of 7k line, that i might have had used for a life line just a month, just to take wear off my lifeline. Also, sliding something new in helps to re-access wear on 'old' line. Sometimes, jsut because i need a longer line than usual for climbing etc., then some more wear, then let it rig. Anything bigger comes along, keep 5/8" ready to go, so ya don't get squeezed into trying to use 1/2".

i place wear on older lines to save back my 5/8 St.Br. and 1/2" Static from wear unless there strength and other charachteristics are really needed. i try to keep a short lifeline in the mix, just to keep that much wear off a longer, newer line. Less weight and storing too. Short rigging line etc.

Eventually they might become lines for dragging, or practicing knots. Arbo line is tough, especially when you really try to care for it, and know it's history.

IMLHO

 

[Roger_Barnett]

Re: If 5/8\" line enough is 3/4\" really better

I use retired climbing line for rigging all the time. And some of them are a few years old at the time. The key is to only use them for light rigging, such as lowering small conifer limbs, or pulling over a smallish tree.

Here's our current arsenal:

1 1/2 inch NE Treeline, about 300 feet long, for long light work, such as speedlining or lowering small, high tops.

1 1/2 inch white Yale 16 strand, 150 feet, bought new only for lightrigging, as it was cheap

1 220 foot 1/2 inch double braid, bought specifically for a 10,000 lb tensile line for the Simpson Chain saw capstan winch. But we use it all the time. It is now 150 feet long.

Brand new 283 foot Puget Sound Ropes 9/16 double braid, about 13,000 tensile.

Brand new 3/4 PSRopes 200 foot. To replace my years old 3/4 inch Wall double braid.

Plus numerous old lowering lines or retired climb lines, as short as 15 feet for tieing plants back, etc.....

I want the 3/4 inch for it's extra safety margin, so have no need for 5/8th. The 9/16th is great---I've never had that size. already used it twice, once to rig leaning alders in one piece with the Hobbs, from over a fence. Today, we used it to straighten an alder that had been forced into another alder by a huge rotten hemlock that fell. Used the chipper winch to pull the alder up a few feet, then tied it off with the PWrap, and climbed the tree.

Greg, and all others. I can get any size of line you can imagine, and at less than 50 % of retail. Just drop me a line. But I'm not sure if I'd have the time to pick it up and ship it to ya.. However, for the favor, Greg, I'll trade ya fer a set of Liu Bars...you know the low calorie ones..

Check out this rather formidable old codom failure on this mature 125 foot tall Western Red Cedar. Well, thank to this ole topper, it's now 75 feet tall...I'll post story/pics, maybe, or you can check em out at Asite....

 

[Roger_Barnett]

Re: If 5/8\" line enough is 3/4\" really better

Hi again Joe,

Check out my post on page 2 of the "lanyard length" thread.

Arborist lines in normal use, be they 12 strand, double braid, climbing or bull, have little significant load absorption qualities. All have much less stretch by a factor of 1.5 to 3, than static line, normally used for rescue, caving and top roped rock climbing.

So, while you can't call them dynamic lines, they do have just enough stretch to slightly reduce peak shock loads, as compared to a synthetic high tech line like spectra, which stretches under 1.5% at 40% load.

Stretch under loads of ~3-10% tensile, for Samson Arbormaster, is 1.1% to 2.7%, if I recall the stats correctly. And polyester double braid has similar stretch characteristics, 4% at 10% tensile, 8% at 40% load. Nylon, however, is very dynamic, stretching 8% at 10% load and 17% at 40%. And true dynamic rock climbing line will stretch up to 70% before failing. Puget Sound Ropes has a graph of stretch at various loads for most of their lines. http://www.psrope.com. Also, go to the Samson website for their new very nice catalog. Samson's double braid spec sheets show less stretch than PS Ropes, the lines I just purchased.

Attached is a pic of an old previously topped Doug fir that we spent about 17 man hrs total giving it a thorough branch lightening.