DIY Air Cannon for tree (and roof) work (1 Viewer)

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How are you learning the ins and outs of tree climbing? Any reading/videos or just working with a crew and learning on the job?
 
just watching tons of training videos. Too old to work with a crew. It's really a young man's game. The problem with vids is that it is very easy to underestimate how difficult a specific task is when you see an expert doing it. This weekend I decided to practice limb walking and cutting a big limb. Well, turns out limb walking is not that easy if your tie in point is in line with the limb. Obvious, of course, since you have no leverage, but still unnerving when you need to balance on there. I guess nobody does videos of that specific issue, so I was not mentally prepared. Then I wanted to see if I could just hang from the limb itself to cut it. Well, actually doing it (vs watching somebody doing it) was very physically uncomfortable and not going to be easy at all to maneuver. Stuff like that. It really is quite a difficult set of skills to acquire. And gravity is a b@tch. Of course, it does not help that I'm doing it on the cheap. Using knots instead of mechanical devices. All the gear is very expensive, I'm guessing because only pros use it and it's therefore tax deductible for businesses and at the high rates they are charging they don't care. You can do all of it with knots, but it's much harder. Having said that, it's very enjoyable to learn and quite interesting skills. As stated earlier, the knots aspect is really fascinating. Never knew there was a world of knots out there with very specific and generally contradictory requirements to achieve. Doing just recreational tree climbing would be great too and maybe better to start with, but it's great to save a ton of money by doing tree work yourself (although at considerable risk admittedly).
 
I would imagine that climbing/spelunking/rescue knots would be the most applicable knots. What knots are you using and what type of line?
 
yes, all those sports/disciplines use similar knots. Although one type very important for tree climbing -if you don't use mechanical devices- are friction hitches. Those knots allow one rope/knot to move up or down another one under light or no load but will "lock up" immediately if there is any significant load. It does help a lot with climbing up a dangling rope especially, which you don't need to do as much with rock climbing etc. Picture a rope hanging from a tree that you need to climb. Contrary to what people may think, arborists don't usually climb a tree by climbing up on wood from branch to branch, at least near the ground, they normally climb up a rope. So you need to climb up that rope. If you are a superathlete you could climb just by pulling up with your arms but most of us can't do that. And I sure can't with another 20 lbs of gear on my saddle (belt). So typically you'd pull up (possibly with some leg assistance) a foot or so, lock yourself to the rope with a friction hitch, stop/rest, and do it again, till you're all the way up. That's where the friction hitches come into play. Also when moving around the tree, you need to constantly adjust the length of the rope, which you can do with a friction hitch. But you still want to be sure that if you fall, the knot will tighten asap and you won't plummet down. Yet, after it tightens down, you still need to be able to move it again at will. Tricky. It does indeed work if knotted correctly, but sometimes not that smoothly. One of the better known friction hitches is the Prusik knot. Some situations in rock climbing or rescue where you may want to use that sort of hitch would be self-rescue from a crevasse, or climb back up a rappel rope if it's too short (no fun). In fact, one of the most awkward bad situation in tree climbing (or rock climbing, spelunking etc) would be to be halfway up a rope and be stuck there. Exhausted or flat out locked tight to the rope under your own weight. Not good. So I always take up a bit of extra rope, and maybe an ascender and a descender with me. With those you can hopefully move up or down. It would never be forgotten if my SO has to call the fire department to get me down ... :)

As to the climbing rope, you normally would want to use a static rope (i.e. with no stretch) to conserve energy climbing. This is normally OK as far as falling because in tree work you won't freefall much at all if you use proper technique, you always want the life support rope to be fairly tight. This is very different from rock climbing when you may routinely fall several feet if you do lead climbing, and you absolutely need a dynamic rope with a lot of stretch. If you fall several feet on a static rope you will probably get badly hurt (like broken back etc).
 
Sounds like Prussics and similar then. Very much an Aid Climbing situation, I suspected as much. A decent set of Jumars* would be easier......

Kern-mantle static lines then. A Prussic isn't going to work well on a laid rope.

*likely dating myself using that name, probably not even close to current equipment but they're what I have.

EDIT: Went looking to see what's out there in ascenders. $100/pair for these doesn't seem too bad.
 
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Yes, Jumars used to be the state of the art some time back. Turns out I scored several for free on Craigslist so I'm set with those. Ascenders are great but many will damage the rope when you use them, so I try not to. Still I usually take one up with me in case of an emergency. An ascender alone will not solve it all to climb up, though, you'll likely want to have some rope for a foot assist (although conceivably you could use the dead end of your life support rope for that instead in a pinch).

What I really want is a mechanical Prusik like a Petzl ZigZag. Dang, those are nice. But at $300 or so, I'll keep using knots for a bit longer.... The basic problem with Prusik knots, though, is that they sometimes tighten up so much that they become hard to move even with no load. Especially if the ropes material and/or diameters are not ideal. That's an issue when limb walking especially.

Added: NT, since it sounds like you know a lot about this, I should add that some of the issues I've had with Prusik hitches may well have been due partly to my using an old-style 12 strand rope rather than the newer 16 or 24 strand ropes.
 
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I've still got my caving gear from the late 80's / early 90's... It's been awhile since I've used any of it. I wouldn't trust the rope anymore, but the ascenders and such is in good shape.
 
I started rock climbing in 1979 when I took a Basic Mountaineering Training Course. I've climbed on and off ever since. My use of the gear in the last ~20 years has been more for exploring mines than climbing. I may know a lot about the topic, but I haven't kept up so I'm sure that big chunks of my info is out of date.

My ropes are not safe any more either. I know one of them has to be 30 years old. Even though it's been kept in a cool, dry place most of it's life I'm sure it is beyond done and needs to be cut so it can't be used. The "goldline" is probably OK given that they are what they are (think that I'll move it to vehicle etc. use), but both kern-mantles (one each static and dynamic) should be retired. My climber tenant would be appalled that I even still have ropes that old.

I've only ever used Prussic loops for self-belays, never for actual Aid Climbing. Those that I have (which should probably also be retired) were made from 9mm kern-mantle line.
 
there are videos out on YT where folks test old ropes. I remember one where they got ahold of a 40 year old caving rope found underground and put it on a tester. Not sure, but I vaguely remember it showing less strength than a new (same) one, but not dramatically so.
Be that as it may, it's all about how many chances one is willing to take. It's certainly one of those things where you want to be extra careful, but it's also easy to be paranoid for little or no gain. But the main life support rope, that one I'm paying attention to... If I start having doubts, I'll just retire it to non life support roles.
I think it's fair to say that in general metal hardware is likely just fine being plain old but soft stuff like ropes and webbing, that's different.
 

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