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<Tom Dunlap>
posted
Cabling and bracing of trees is a practice that too many arborists are afraid to use. There is no good reason not to use this tool to aid trees.

I am very familiar with the installation of cabling and bracing systems. Has anyone ever developed a set of standards or guidlines to aid them in the descision of cabling or removing. How about when to even cable at all?

I am not looking for a firm "recipe" to follow, just some guidelines.

Thanks for any thoughts,

Tom
 
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<Russ Carlson>
posted
Reply to post by Tom Dunlap, on December 10, 1999 at 18:15:58:

I believe the ANSI* A-300 committee is currently workong on a set of guidelines for cabling and bracing.


*ANSI is under a new name now- anyone know what it is?
 
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<Scott Cullen>
posted
Reply to post by Russ Carlson, on December 10, 1999 at 18:15:58:

Russ,

1. ANSI A-300 Cabling Standards are in draft, maybe even ready for publication. NAA should be able to confirm. I'm not sure, however, that the standards go directly to Tom's query.... which trees to cable? I'll have to re-read the draft. I was fortunate to be trained in a company that did a lot of cabling and by a foreman who had done lots of rigid bracing and cavity work as well. I think experience is a big part of the decision process. Tom is right, there are probably a lot of arborists who don't have that exposure. I know I've sensed a real reluctance to cable among urban foresters who do not have tree care backgrounds where they get that experience.

2. As nearly as I can tell by a web search ANSI is still ANSI and publishes standards as such. It has two cooperative programs aimed at providing access to other national and international standards. They are NSSN and STAR.
 
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<Russ Carlson>
posted
Reply to post by Scott Cullen, on December 11, 1999 at 16:53:17:

For those seeking to know when a tree should be cabled, the best background is a basic high school course in physics. Understanding forces, levers and vectors is as close to a prerequisite as there is for cabling and bracing. Then you need to understand the tree's structure.

The physics is not high level stuff, just the basics of applied forces. It's mostly intuitive anyway- If you push here, it will go that way.
 
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<JPS>
posted
Reply to post by Tom Dunlap, on December 10, 1999 at 18:15:58:

I do a little bit of it but only if it is straght forward with only a few lines needed.

split crotch =recomendation for removal. if they want to keep the tree I contract for the C&B with the recomedation for removal in wrighting & statement that it will not prevent failure.

included crotch=same with out recomendation for removal.

if either of the above is noted and an intrecate system of lines is needed to proved the "harmoniouse" movement needed I recomed someone else.

how about "wolf limbs" or other a symetrycal growth paterns?
 
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<Russ Carlson>
posted
Reply to post by jps, on December 10, 1999 at 18:15:58:

There is nothing mysterious about cabling. It is not difficult to learn, but does take some study and some understanding of the forces involved with the tree, wind, gravity, etc.

The first part is the purpose of cables and braces. It is not (should not) be intended to hold the tree up or support the full weight of a limb, in most cases. Cabling of weak crotches (the most common application) is meant to reduce the forces applied to the weak point in the tree's structure. Those forces occur from gravity pulling the limb down, and/or from wind placing forces on the crotch in a way that will strain it beyond its capacity.

If the basic guidelines of cabling are followed, the likelyhood of breakage of the limb due to the cable itself is extremely small. Using eyebolts, proper spacing and placement of the anchorpoints, and making sure the hardware is not placed where there is decay, keep the risk low. Matching the hardware to the job is also very important- know the ratings of the hardware, and use the appropriate sizes of cables and bolts.

Weak crotches pose a second risk- while wind causes spreading of the cratch until it fails, it can also cauuse torque or twisting that will allow it to fail. This can be stabilized with one or more through bolts, and should be considered of the structure indicats that twisting or splitting could be a problem.

The techniques and guidelines are described in The Tree Climbers Guide and the Arborist Certification Study Manual, both available from ISA.

Next time you get a nice breeze, sit (in an open area) and just watch a big tree dance in the wind. Watch how the limbs sway in relation to each other, and how they move. As the close and spread, imagine how a cable might work on them, limiting the motion.

The cables do change the stress patterns within the tree. And you should have some basic knowledge of where those forces are redirected. And you need to understand the rest of the tree's structure. Cabling a high crotch may be futile of the lower truck is ready to collapse from decay, or if the crotch itself is badly decayed. But using a good support system can prolong the useful life of the tree by many years. Sure, there are caveats- inspect regularly, replace it periodically, etc. But apply a little salesmanship, educate the tree owner as to their responsibilities and those can become non-issues. Cabling is not difficult to learn, and should be a part of every good arborist's package. That's why it's part of the CA Exam.
 
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<Peter Torres>
posted
Reply to post by Tom Dunlap, on December 10, 1999 at 18:15:58:

First of all, no one who advises against drilling trees, or taking Pressler cores, should cable. These people must use the Cobra system.
Other than that, I am willing to cable trees if the weakest vector can be "dynamically immobilized" by one or more cables. In other words, you get a good angle or angles, in 3-d space.
I will cable a tree that I know can still fail in a sideways direction to the cable, to extend the utility of the tree, after discussing same with owner, and realizing that the eventual failure will at least be redirected, into a better place, and hopefully not catastrophically. I do not make a big deal about documentation, but I realize that many people do.
If there is decay in the crotch to be supported, I will not cable. Fungi rule. The addition of steel cable will not have any effect on active decay (pathogenic) or saprophytic (because the wood is all ready past tense). The cable can still redirect the failure, but not predictably.
 
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<Scott Cullen>
posted
Reply to post by Peter Torres, on December 10, 1999 at 18:15:58:

Peter, how frequently do you encounter trees with a potential for failure sideways to the crotch? As Russ noted earlier in the thread the most common application of cabling is to support a weak crotch.... most typically in my experience a typical "V" shaped crotch, with included bark... with the cable installed generally perpendicular to the crotch seam or included bark. That is the most common situation that gets corrected. The cable effectively corrects it because it stops the moment in the same vector as the system might otherwise fail.

What factors or characteristics would you use to identify a system subject to failure in a sideways vector.... i.e. not perpendicular to the crotch? Are there factors other than decay?

A secondary objective of cabling - as often cited in the past, I'll have to take another look at the new A-300, was to restrain the member relative to a target in the event of failure. The branch or leader breaks but the cable holds it in the tree. My intuitive sense was always that that was the reason the old cabling standard had guidelines for matching cable strenght to limb or leader weight. Stopping the moment to prevent failure only requires a small fraction of the total unsupported weight of the limb or leader.... the system is largely self supporting to begin with. Nature and proximity of tragets and the ability of the syatem to perform in this manner might also influence selection of candidates for cabling.
 
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<Mark Goodwin>
posted
Reply to post by Scott Cullen, on December 16, 1999 at 22:23:11:

As one who is not experienced at cabling/bracing, I have many questions about details not covered in the Arborist Certification Guide.
How often are the various types of cabling systems used (e.g. direct, triangular, box/rotary, hub and spoke)?
Having never seen a Cobra system, how is it attached to the branches?
How is cable tension determined and adjusted on a cable that is being inspected from year to year?
When 2/3 the distance from crotch to tip is many feet higher on one branch than on another, and a cable is installed between the two, does it matter much if the angle of the cable is not perpendicular to the axis of the branch?
In other words, should the cable be pulling straight away from the branch on a perpendicular angle?
Or is it O.K. to have the anchor installed on a diagonal through the branch, with the cable pulling in the same line with the angle of the anchor?
Is the final adjustment for cable tension made with turnings of the left and right hand threaded anchors?
 
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<Scott>
posted
Reply to post by Mark Goodwin, on December 17, 1999 at 07:43:25:

Lots of good questions Mark. I'll try to answer the ones I can... I hope somebody else out there pitches in. I should point out it's been 15 years since I was in the installation end of the business, so some of my recollections are musty.

1. My experience was direct was most common. Triangular next. Box and hub & spoke much less seldom, except perhaps in large shrubs or small clump trees like white or gray birches.

2. I've only seen pictures, but I think Cobra is attached by an eye splice of sorts.

3. In my experience, cable inspections are primarily for condition of cable and hardware (are they rusted, nicked, frayed, broken?). I have installed very few systems with a turnbuckle or other tensioning device which allows adjustments. I can't seem to locate the draft A-300 right now to check on the current standards.

4. I think we need to clarify the "perpendicular" issue. In my post above I used perpendicular to mean the lateral direction of the cable relative to the line of the included bark in the crotch. I think you're using it here to describe a cable which is level end to end. I think the 2/3 rule of thumb is intended to minimze the flexible, unsupported stem above the anchor point, minimizing the chance of breakage above the anchor point while staying in a portion of the stem that provides support in the cabling system (let me know if that makes sense). The ideal is if both stems are approximately the same height and diameter. If one is the "lesser of two equals," i.e. the crotch is likely to fail in either direction but one side is smaller, I think I would position the anchor point as near as possible to the 2/3 point in the larger side and try to minimize slope down to the other side. But a strong attachment point at a relatively stiff point in the smaller side seems more important. So, to answer your question slope is OK. The anchor hardware is probably OK installed level if the angle is not too great and the weight is not likely to bend or break the hardware. If using a through bolt you'd want the eye up tight to the bark so you're not pulling at an angle to an extended shank. If using a lag hook you need to be sure the hook is not left open if you're on an angle. If there is great weight you might want to drill on an angle, all the way through for a bolt, but that's a longer hole, longer bolt, more work, more damage. If the cabled stem is much smaller and it's the breakage of that stem alon that's being avoided, the larger stem is merely an anchor point and you could come way down below the 2/3 point on the larger side.

5. I can't answer this as you've posed it. I've never used L & R threaded lags. I have always preferred through hardware (drop forged eyebolts). Final tension is usually achieved by drawing in on the bolt by tightening the nut. If the cable length has been estimated properly both eyes should wind up pretty close to bark without much exposed shank.... but exposed shank is not a big deal IF the cable does not pull up, down, left or right of the axis of the hole and bolt. With a long cable or interfering growth it's sometimes helpful or necessary to take up the bulk of slack with a come-along attached to the cable with a cable grip. This is also the way I was taught to tension the cable to be slipped or spliced onto a lag hook.

I'd be interested in other perspectives out there.
 
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<JPS>
posted
Reply to post by Russ Carlson, on December 13, 1999 at 20:39:35:

I did not mean to imply that I use capling as a system to suport tre parts.

I understand that C&B is used to releave stress in a weak part of a tree, in the situations where i will use it is when there is a simple weak crotch. The system is used to cause the stems involved to move together in the wind.

I also understand that when one puts the hardware in one changes the dynamics of the plant.

I tied (and failed again) to get across that I understand the basics, but was looking for thoughts on other things I have seen.
 
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<JPS>
posted
Reply to post by Scott, on December 17, 1999 at 12:21:45:

As I have stated, I only do "easy" jobs so I only have used direct and triangle methods. The way I was taught is that the system is not used for support but to cause the stems involved in the weak spot to move in sympathy. Hence no real tension is needed and if installed in "leaf off" some slack should be used.

Or am I once again only seeing part of the picture?
 
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<Russ Carlson>
posted
Reply to post by jps, on December 14, 1999 at 22:43:49:

Didn't mean to question your understanding of cabling, John. I guess I was writing more to the underlying questions than a direct response to your post. Sorry, if I offended.

You did ask about the odd structure, such as wolf limbs (the stray that got away, and outgrew the rest of the canopy). This is where the physics lessons help the most. Still, there are many cases where cabling just won't work. If there is no place to tie the limb to with adequate support, then alternatives must be explored.
 
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<Russ Carlson>
posted
Reply to post by jps, on December 17, 1999 at 16:45:30:

Like most things, there are no absolutes, so some cases may vary. But your perspective is correct for most cable jobs.

The concept is to limit the tension at the weak point. Since the tree obviously held to the date of installation, it should be able to tolerate some amount of tension on the crotch. This means that the cable does not have to be bow-string tight- just taut enough to limit excessive movement. In fact, there are many who argue that the cable should be a bit slack, to allow the movement that will encourage development of response wood growth.

Tightening the cables is best done by using a cable winch or come-along to pull the limbs together a little, then installing the cable, finally releasing the cable. Tightening the eyebolts or lags under tension can lead to significant bark damage around the holes.
 
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<Russ Carlson>
posted
Reply to post by Mark Goodwin, on December 17, 1999 at 07:43:25:

>>When 2/3 the distance from crotch to tip is many feet higher on one branch than on another, and a cable is installed between the two, does it matter much if the angle of the cable is not perpendicular to the axis of the branch?<<

This will depend on the relative sizes of the limbs, as Scott suggested. You want the most support for each limb. Placing the cables higher on the limb provides the better reduction of forces to the fulcrum point (crotch).

If a larger limb is not likely to break, but is providing support to a smaller limb, the placement of the cable on the larger limb is not as critical. It can be much lower on that limb, and in fact, it may be better to place it lower, and reduce the strain on that limb. The limb being supported should have the cable higher, if it is supporting a weak crotch.
 
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<Scott>
posted
Reply to post by Russ Carlson, on December 17, 1999 at 20:38:00:

Using a come-along to pull the limbs together has a lot of merit. And certainly if there is a lot of tension on the system taking up the slack by tightening the nut might cause some damage. But why so much tension? if the limb needs to be taken up under tension maybe this is a non-typical installation.

For the minimal tension - or even a bit slack - installation tightening the nut should not cause much bark damage. In fact some recommendations call for removing the bark under the washer with a gouge. Other (anecdotal) sources talk about that compression of bark effectively being as good as countersinking with the gouge.

BTW, if the nuts are not brought up reasonably tight it becomes even more important to peen over the threads at the cut bolt end (should be standard practice) so the nut can't vibrate off.

As always it comes back to understanding the system experience with methods.
 
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<Scott>
posted
Reply to post by jps, on December 17, 1999 at 16:45:30:

I think "moving in sympathy" is descriptive... but maybe only partially. As Russ describes, it the two stems are already standing there they are largely self supporting. The cable is not intended to support their dead weight. When a crotch fails it is because the stems move apart more than normally - say in a wind storm or under ice or snow load - and the wood fibers below the included bark fail under tension or shear (they are pulled apart which is the opposite of being in compression or squeezed together). When that happens the system is no longer self supporting and the weight of one or both stems continues to split the stems apart. As a stem bends over the effective weight on the bottom of the stem gets much greater and the stem fibers fracture, like snapping a pencil in two.

The purpose of the cable is to prevent movement of the stems beyond the point where the shear failure would occur leading the the complete failure. It's called "stopping the moment" of force. So it's not just that the stems move in sympathy, movement is limited.

I think one of the reasons for some cable tension is to prevent "snap" in cable movement. If you try to slowly stretch a string till it breaks you probably can't. Bring your hands together and pull them apart quickly and you can easily snap the string. A slack cable - and the attaching hardware - are subject to the same sort of forces. So I think some tension, or at least minimal slack, is necessary for that sympathetic movement to prevent "snap."
 
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<Mark Goodwin>
posted
Reply to post by Mark Goodwin, on December 17, 1999 at 07:43:25:

Thanks for the replies. Here are a few more questions:
1) Are Tree-Grips as strong as a cable "splice"?
2) Are cable clamps (2or3) as strong as either of the above?
3) Which method of attachment do people prefer, and why?
4) What tools do you generally use when doing cabling?
5) How would you handle a case where a bit breaks off inside a branch or trunk?
6) When using the come along, are slings used at the ends to protect the cambium?
7) If a generalization could be made, what size of common cable would be used generally with what size limb? How is the weight of the supported limb calculated? And is the rated weight strength of the cable allowed to be used only up to a certain percentage of the calculated weight of the limb?
8) If bracing rods are used at a close junction of three scaffold limbs (silver maple), and the rods will be at close vertical proximity but crossing, does the vertical spacing matter as much as if the rods were parallel? (It seems to me the rods need mainly to be aligned with the attachment points of the limbs.)
9) Do the rods need to be driven in, if the holes are 1/16" larger, or do they slip right in?
 
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<Russ Carlson>
posted
Reply to post by Scott, on December 18, 1999 at 00:29:30:

My point was not that there should be much tension, but at the same time excessive slack is not desirable either. The slack needed simply to install the cables may be too much. A little tension with a come-along will provide the slack needed to install, without putting the cable under great tension when released. As you said, experience matters.
 
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<Russ Carlson>
posted
Reply to post by Mark Goodwin, on December 17, 1999 at 12:21:45:

Let's take them in order.

1) Are Tree-Grips as strong as a cable "splice"?

Properly installed, the Grips will hold as much or more weight. The key issue with the Tree Grips is proper installation of the thimble. DO NOT USE the grips without a thimble. They will flex at the bend, breaking within as little as a few months.

2) Are cable clamps (2or3) as strong as either of the above?

Clamps can slip under shock loading, which is why they are not included in most recommendations for tree cabling.

3) Which method of attachment do people prefer, and why?

Eyebolts are considered to be the strongest and best attachment method. Lags only hold from one side, and can pull out if there is any decay in the stem. Eyebolts are anchored on the back side of the limb by the nut and washer. Make sure the threads are peened to prevent the nut from backing off, too.

Eyebolts are stronger than hook bolts. The latter can bend and straighten, allowing the splice or Grip to loosen and maybe slide off the hook. Drop-forged eyebolts are also higher rated than bent eyes, even if welded. In short, donÂt cut corners on the hardware. The extra cost means a better job.

4) What tools do you generally use when doing cabling?

Aside from the cabling supplies, you need a drill bit to extend through the limb, and a machine to drive it. The old hand brace is the stock-in-trade for this, but the various power drills make the job much easier. The size of drill will depend on the size of limbs and the frequency you do it.

5) How would you handle a case where a bit breaks off inside a branch or trunk?

Start a new hole, preferably about 12 inches above the first, and perhaps offset slightly in vertical alignment.

6) When using the come along, are slings used at the ends to protect the cambium?

Yes. Use a Havens grip (cable-grabber) makes it easier, since you donÂt have to return to the first side of the job to retrieve slings and winches.

7) If a generalization could be made, what size of common cable would be used generally with what size limb? How is the weight of the supported limb calculated? And is the rated weight strength of the cable allowed to be used only up to a certain percentage of the calculated weight of the limb?

There are published standards for the cable/limb size match ups.

Calculating the weight of the limb is difficult. One approximation is to calculate the weight of a pole the same length and diameter of the limb being cabled. IOW, take the diameter at the base of the limb, determine the cross sectional area, multiply by the length of the limb to get the volume. Green wood weighs in at about 65 to 70 pounds per cubic foot (this can vary a lot, depending on species, etc.)

8) If bracing rods are used at a close junction of three scaffold limbs (silver maple), and the rods will be at close vertical proximity but crossing, does the vertical spacing matter as much as if the rods were parallel? (It seems to me the rods need mainly to be aligned with the attachment points of the limbs.)

There are several reasons for not placing rods/bolts in vertical alignment. Decay columns can form more readily when multiple injuries are vertically aligned. Lateral torsion also places stress on the fibers. Offsetting the rods will spread the torsion along different lines with in the wood. This is most important on those species that split readily. There must be a compromise in placement to achieve the desired goal and maintain adequate spacing and alignment of the hardware.

9) Do the rods need to be driven in, if the holes are 1/16" larger, or do they slip right in?

If you make a hole 1/16 inch larger than the rod, you may be able to slip it through easily, but will probably need to drive it in with a mallet. A sharp bit makes it easier. Put a nut on the end of the rod, in case some of the threads are damaged in the process.

I hope this helps. Fire away with more questions, if you have some.
 
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<Scott Cullen>
posted
Reply to post by Russ Carlson, on December 18, 1999 at 18:11:33:

Russ has pretty well covered the bases on the questions. But here are a few additional comments.

RE: 4. Tools will vary by method, but assuming you may use various methods as best suits the situation, a full kit would include them all. Here are a few of them.... if you use lags a suitable too to turn them in. You can use a pipe wrench, pliers, a pielc of cut off bolt; but the best is a specialty tool thta's in the catalogs made of cast aluminum (I think) with a pointed and bent end to get into and grab the hook while you turn. If you use bolts you need a wrench to thighten the nut. You can use an open end (fixed or adjustable) but they tend to slip off the nut. You can use a box wrench, it won't slip off as easily. Best of all is a "through" socket with a ratchet handle. They allow you to slip a long bolt end through the socket and grip the nut... the ratchet saves a lot of time/effort if limb alignment noes not allow 360 deg. rotation of the handle. The ones we had years ago I think were designed for iron workers, can't find them anymore. The ones that you see in the late night TV infomercials don't go up to the sizes need for tree work. There is a line made for the utility industries I think by a company named Lennox but I can't find the catalog. If you use bolts you'll need a hacksaw to cut the ends off. Make sure the type you use does no have a handle that falls apart (1/2 goes to the ground) if the blade snaps. Spare blades. A metal hammer to peen over bolt ends as Russ suggests (but if you cut 2/3 through with the hacksaw and then bend the rest of the way when in breaks it will usually squeeze a thread and prevent backing off). If you hand splice, good linesman's pliers (Kline is the standard from an electrical supply house). If you do a lot of cabling, cable cutters to cut a length from the reel. They look like pruning loppers. Greenlee makes them. Save a lot of time compared to hacksaw or pliers and leaves a clean cut. A tool bag to take them all up in the tree. Kline makes a good one with a leather bottom (ever spear a groundsperson when the sharp end of the drill bit goes through the bottom of a cavass bag?) May sound obvious, but a spare assortment of nuts and thimbles. Nut falls out of your hand and lands in the snow, whole job shuts down while somebody goes off site to get a nut. Russ mentioned slings, cable grips, rubber mallet. They are hard to find these days but a rubber-composition mallet is better than the soft cushiony kind. Proper size bits (both diamter and length) and whatever drill you think you need. The hand brace is still very useful and for reasonable size holes may wind up quicker than rigging the power drill and lugging it around the tree. Shop the catalogs for a brace with a large off-set in the handle. More leverage = less effort. They too are hard to find. You may find that if you use both hand brace and power drills you'll need bits with different pattern shanks.

RE: 5. Relates to 4. Buy good bits and try to avoid extensions. Retract the bit frequently to clear the chips and reduce friction-torque. Don't reverse the bit out, keep the drill turning forward as you pull it back out. Keep the bits sharp (which mostly means avoid getting the dull).

RE: 7. Russ, I don't see the weight tables in the draft of A-300. Do you know if they've been dropped? I don't know if the old NAA standard is still available including the table. In practice, I can't say that I ever did a weight calculation. It's an inexact business anyway; the real purpose of the cable is to "stop the moment" not to support the dead weight. I think we studied the tables at first and then settled on size threshholds for 1/4, 5/16 or 3/8 cable but I can't recall them. I should point out those were all soft cable sizes.

RE: 9. It will depend on the length of hole and how much the bit wandered. Best never to count on an easy slip through. As an alternative to knocking it through you can chuck the bolt in the drill and wind it through. You can make up an adapter (if the chuck dia is less than bolt dia) using a nut with a smaller shank welded to it. This, BTW, is the typical method of installation for "screw-rod" which is inserted in a 1/16 undersize hole and relies on thread grip in sound wood rather than washers and nuts for holding power.
 
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<Russ Carlson>
posted
Reply to post by Russ Carlson, on December 18, 1999 at 18:11:33:

Forgot to finish the toolkit:

Wrenches to fit the nuts.
Pipe wrench, for turning in rods, tightening nuts, holding rods while tightening, etc.
Pliers, heavy-duty with wire cutters. Essential if splicing maleable cable.
Cabling tool- for turning in lags, separating cable strands.
Hacksaw, for trimming excess bolts and rods.
Bolt cutters, for cutting the cable to length.
Mallet, wood or hard rubber, to drive rods in.
Ball-peen hammer, to peen the ends of rods and bolts.
Bandages, required if do much splicing of cables (I always manage to scrape the fingers at least once[g])

Don't forget to have plenty of thimbles on hand. It is ESSENTIAL that they be properly installed on ALL cable assemblies. Improper installation or lack of thimbles is (IMO) the #1 cause of premature cable failure.
 
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<Tom Dunlap>
posted
Reply to post by Russ Carlson, on December 18, 1999 at 18:11:33:

A few years ago I bought a set of 18 volt DeWalt tools. I use the half inch drill for shorter bolt holes and all pilot holes for lags. The reciprocating saw is great for cutting bolts off. Be sure to put a lanyard on the cordless tools and attach it to your saddle or the tree.

I have read for years this line of peening ends of bolts. I don't buy that for a second. Think about it, how is the cable, bolt, or nut going to turn? No way! For neatness I will peen once in a while. One guy peened bolts that were close to the ground so no one could unscrew the nuts. That doesn't hold water because the wrench that is going to be needed to unscrew the nut will straighten out the threads. Besides, a season of rust will lock the threads pretty good even on plated hardware.

To pound the hardware you might look into a dead blow hammer. They look like a big plastic mallet. The head is filled with shot so that the impact does not allow the hammer to bounce, hence the name, dead blow.

I bought a gas powered, reversing drill for long through bolts.

All of this talk of tools reminds me how much I like to use Cobra. The bummer is that I still ike to use tools!

Tom
 
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<Scott>
posted
Reply to post by Russ Carlson, on December 19, 1999 at 01:27:19:

I forgot the pipe wrench, good addition. I have to suggest a cable cutter is better for cutting cable than a bolt cutter which tends to squash and flatten the cable before actually cutting through. (Maybe that's why you need all those bandages. Now I found them much more usefule after bashing my hand with the ball peel hammer.)

Plenty of the RIGHT SIZE thimbles. At least be sure not to use under sized thimbles. Many people use one size over to get a good seat for the cable and if you're careful it doesn't seem to be a problem.
 
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<Scott>
posted
Reply to post by Tom Dunlap, on December 19, 1999 at 01:27:19:

Sorry, I have to disagree here Tom. I have definitely seen nuts back off (not on my own installations of course). It is precisely becasue the bolt and cable assembly don't turn that vibration can cause the nut to turn. It's more likely with very little tension on the system and there should usually be enough tension to prevent it, but it's still possible. Galvanized (rather than plated) hardware will take quite some time to rust and the cut end doesn't rust enough to prevent the nut backing off, so that's not a defense.

I think I mentioned it in the other post, but peening is really an extra step. If you cut only 2/3 or so of the way through with the hacksaw and bend-break the bolt the rest of the way you'll usually deform a thread enough to prevent the nut backing off. Either way it's a minimal extra step that's just good insurance.

It's OK, even if you use Cobra for all your cables you'll still need the neatest tools for the bolts and rods.

18v cordless recip sounds perfect for large bracing bolts. Do you find it's worth the effor to lug around the tree for the 1/2" eyebolts? What's your battery life been like with the 18v? My 12v DeWalt's 1st set laset about 2 years. The 2nd set seems to be degrading faster... they don't hold a charge as long. I'll upgrade to 18v when they come out with the 18v Dustbuster for the shop and jobs around the house.
 
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