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Guru

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Cross Bow Information

05/17/2017 1:20 PM

Hi, I know there is agent who makes bows and I now need to ask for his expertise, advice and possibly, (hopefully) his assistance in producing/procuring a cross bow.

I am in need of a cross bow to fire a blunted bolt, to a distance point of no more than 500m, and to carry with it, a kevlar line of approximately 4mm diameter, across that distance.

The need is for stringing transmission lines across dense forest where a drone cannot be used, (where I am now the drone is illegal to use), and line of sight for done use is very limited. It is also expected to utilse the crossbow for carrying the pilot chord across some gorges.

Once the string is across a larger diameter rope will be attached to the kevlar string and the kevlar string used to pull over the rope, until we can install the string rope for conductor stringing. The cross bow is consider as I should need to eliminate the archers paradox and hopefully set the cross bow up to fire automatically, and remotely via a laptop which would have a basic programme installed to allow for wind factor, setting up the correct trajectory angle in the possible hope that the bolt arrives at the next transmission tower and is captured in a collector circle, or V shaped collector, that the string can be easily captured on the next tower.

If the bow creator, or anyone else has any good input to this, I would be interested to hear from them.

Points of note:

1.Drones are not an option, for now.

2. Access by foot or vehicles between towers in most areas has much limitations.

3. Helicopter use is limited due to various constraints; sensitive regions, down wash from blades, cost, no fly zones etc.

4. Considered hellium and hot air balloon system using ContiTech HeliMax balloon material, however it cannot be controlled.

5. Cross bow is a possible solution so if he bow maker can add comment and advise if a cross bow will suffice at that distance, with a drag of a kevlar string, I should like to hear from him with a view to progressing a design and solution and a cost.

Look forward to any posts.

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#1

Re: Cross Bow Information

05/17/2017 1:27 PM

Our resident bow expert is Del, you should message him for advice.

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#4
In reply to #1

Re: Cross Bow Information

05/17/2017 1:53 PM

Cool Thanks. I forgot who it was but knew he was here somewhere.

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#7
In reply to #1

Re: Cross Bow Information

05/17/2017 2:22 PM

Done, thanks for the direction, appreciated. Cheers for that Mr. Nigh.

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#2

Re: Cross Bow Information

05/17/2017 1:35 PM

Did I read that right? You need to shoot a bolt dragging 4mm line behind it, half a kilometer?

I am no crossbow expert, as already stated, Del the Cat is our archery expert, but that seems like a stretch to me.

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#3
In reply to #2

Re: Cross Bow Information

05/17/2017 1:50 PM

According to this, 500 yards (or meters) is doable if you are not out to hit or kill anything.

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#6
In reply to #3

Re: Cross Bow Information

05/17/2017 1:58 PM

No intent on killing anything, just intent on hitting a target collector for the bolt and string and I hope no bird gets in the way of the bolt. Otherwise we wont hit the targeted tower. And that is a lot of kevlar string to pull back and coil on a 54m tower.

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#8
In reply to #3

Re: Cross Bow Information

05/17/2017 3:03 PM

Big difference between shooting that far and doing it dragging a cord.
I don't think is feasible except by building something very specialised and doing a lot of experimentation which would take time.
There are plenty of compound crossbows with impressive speed figures... but those speeds would drop off if you were shooting the heavy projectile necessary to drag the line.

I'd think a rocket, like the things they use to shoot lines to ships in distress would be better.

There was a recent article about a guy doing something similar with a Warbow, but it was much shorter range.
I'd think 200m would be a sensible maximum range.
Of course if the towers are 500m apart, it's a 250m shot from the middle to each tower.
Del

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#10
In reply to #8

Re: Cross Bow Information

05/17/2017 3:34 PM

I bet you're right, dragging line behind it would shorten the range.

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#17
In reply to #8

Re: Cross Bow Information

05/17/2017 7:50 PM

I'd think a rocket, like the things they use to shoot lines to ships in distress would be better.

Yes that is exactly what I was thinking also. Not sure where you buy these from though.

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#78
In reply to #17

Re: Cross Bow Information

05/21/2017 4:21 PM

I don't know that a rocket in a wooded area is a wise move...

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#79
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Re: Cross Bow Information

05/21/2017 4:46 PM

What I was actually thinking (and probably should have added) was the type which used some sort of cartridge to propel the projectile the line is attached to (not an actual rocket with a line attached).

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#80
In reply to #78

Re: Cross Bow Information

05/21/2017 9:15 PM

Yeah, better to shoot clear of the trees...well above.

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#20
In reply to #8

Re: Cross Bow Information

05/17/2017 11:58 PM

Del--Any way a catapult system could work? Especially with loaded projectiles? Or have I been watching too many "in the past. in the future" movies??

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#25
In reply to #20

Re: Cross Bow Information

05/18/2017 12:13 AM

Yea, high voltage lines companies are all just dying to line up to add catapults to their purchasing cost centres.

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#30
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Re: Cross Bow Information

05/18/2017 3:13 AM

I think any manually cocked device will end up being too bulky or difficult to make.
Medieval siege engines were huge. Rubber cord catapults and crossbows will do it in theory, but you'd have to make V big one and the law of diminishing returns applies.
E.G a 100# draw weight bow doesn't shoot twice as far as a 50#

I reckon you'd have to make a crossbow with a draw weight of about 1000# with a reasonably long draw, say 24" and be shooting a heavy projectile to give it enough energy to drag the line.
Sir Ralph Payne-Gallwey refurbished a medieval crossbow which shot a heavy bolt over 1/4 mile and that was about 1/2 ton draw weight, cocked by windlass. But it had a steel bow which had huge inertia and limited the speed. Modern materials would be better.
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#11
In reply to #3

Re: Cross Bow Information

05/17/2017 3:55 PM

Ok, you learn something new every day, you can shoot a bolt 500m with a crossbow.

But there will be about 2lbs of string behind it, and it is being shot through dense forest. A single leaf, twig, or branch is going to significantly hamper that distance. The longer it flies, the more chance the Kevlar string is going to rub or tangle on something.

As I said, I am no expert in this but it still seems like a stretch to me for that distance.

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#22
In reply to #11

Re: Cross Bow Information

05/18/2017 12:00 AM

What about the new Spectra line being used for fishing and other systems? Many times stronger , much smaller diameter with less resistance...

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#34
In reply to #3

Re: Cross Bow Information

05/18/2017 4:16 AM

But in your link 500m is without a string attached. No chance with a 4mm line. The bolt dia probably isn't that much more. My guess is the mass of the bolt needs to be many times that of the string for it to work. Why not start with the thinnest line he can get hold of, use that for a thicker one and so on (the traditional method)?

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#5
In reply to #2

Re: Cross Bow Information

05/17/2017 1:55 PM

Yep, sure is correct, 500m max, as that is the span distance between some towers.

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#9
In reply to #5

Re: Cross Bow Information

05/17/2017 3:20 PM

You might think about taking that string down in size to spider silk size. Otherwise, you will never hit the 500 m mark in the circle.

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#12
In reply to #9

Re: Cross Bow Information

05/17/2017 4:12 PM

My thought exactly. 4mm Kevlar should be close to 1000lb tensile strength. If you shot 100lb Kevlar, .6 to .7mm, it would drastically reduce the drag. Then pull the 4mm Kevlar with that.

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#13

Re: Cross Bow Information

05/17/2017 4:16 PM
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#24
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Re: Cross Bow Information

05/18/2017 12:13 AM
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#28
In reply to #24

Re: Cross Bow Information

05/18/2017 2:36 AM

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#29
In reply to #28

Re: Cross Bow Information

05/18/2017 2:55 AM

This I think would work....50 psi 10 sec hangtime = 175 fps 1000 ft

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#41
In reply to #29

Re: Cross Bow Information

05/18/2017 10:11 AM

but we are talking 500 m, not 500 ft.

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#50
In reply to #41

Re: Cross Bow Information

05/18/2017 12:03 PM

Yeah so you raise the pressure to 100 psi....

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#51
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Re: Cross Bow Information

05/18/2017 12:11 PM

Flight angle of the trajectory has a lot to do with it.

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#14

Re: Cross Bow Information

05/17/2017 4:17 PM

One would hope that this device is for shooting down drones.

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#15
In reply to #14

Re: Cross Bow Information

05/17/2017 5:55 PM

Punkin'chunkin'!!!

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#16
In reply to #15

Re: Cross Bow Information

05/17/2017 6:51 PM

Punkin' Chunkin' is better then Chunkin' Punkins'.......ewe!!

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#37
In reply to #16

Re: Cross Bow Information

05/18/2017 9:28 AM

what does Punkin' Chunkin' have in common with female sheep? That's a joke, so you don't have to answer, I just hope you get the punch line.

In Russia (the Russia connection): Punkin' Chunkin' is called Pyunkin Chyunkin!

congrats to the all the participants. Now let's rest on our laurels while the impervious leader of the witch hunt finds no there, there. Godspeed to Sp. Counsel Robert Mueller in the quest to find or not to find, that is the question.

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#18

Re: Cross Bow Information

05/17/2017 11:34 PM

I shoot crossbows, and even compound crossbows will not do the distance you're talking about, and rockets in a forest ... could make for a hot time!

I think your best option would be to use a helicopter to run the pulling cord, then go from there.

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#19

Re: Cross Bow Information

05/17/2017 11:35 PM

Speaking of chunkin'

I built a potato cannon back in the day that could launch the biggest spuds I could find well over a ?? Couple hundred yards. Scaling up and using threaded pipes with starting fluid instead of aqua net and PVC.. l bet you could core right through any trees in the way. .. (or not)

I fiber glass wrapped mine out of fear and paranoia.. .. but threaded pipe?

I'd like to try it. Whump!

... Local law may vary. But that is now.. this was then.

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#23
In reply to #19

Re: Cross Bow Information

05/18/2017 12:08 AM

In College, we would take a piece of heavy galvanized pipe, with the ID just slightly larger than a golf ball, dig a hole in the ground, fill it with 12" of water, insert the pipe, drop in a lighted M-80 , 1/4 stick dynamite charge, and then drop in the the golf ball..We could not find even a 10th of them.. They must have been the earliest handheld rocket launchers. You could guide them by holding the pipe. Amazing fun..

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#40
In reply to #23

Re: Cross Bow Information

05/18/2017 10:09 AM

amazing that you survived!!! My brother-in-law got in trouble in Norway on leave from an offshore rig once (with his drinking buddies). They had a drill pipe, beer bottle or coke bottle, red rage wadding, and oxy-acetylene in that welding shop, and they were all snockered.

It fired to just the other side of a major freeway in Stavanger, and the next sound was the local police sirens triangulating back to the source.

Your M-80 experience holding the pipe really has me scratching my head how most any of you and your fellows made to adulthood.

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#27
In reply to #19

Re: Cross Bow Information

05/18/2017 1:53 AM

Do you have a design for this or know where I can locate a basic design to fire a golf ball? I would be looking to fire this off from a tower top, and above the forest canopy so no twigs and trees will be in the path. We just need to hit a collector/receiver on the next tower peak. Thanks.

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#48
In reply to #27

Re: Cross Bow Information

05/18/2017 11:32 AM

Find a golf ball, and take it to a pipe supply house, and tinker with the size. THe end of the pipe must be put into water, as it is nearly incompressable, and all inertia will be out the front. Start with small charges, work your way up. And remember, if the charge fuse goes out, DON'T look down into the bore...!!!

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#56
In reply to #48

Re: Cross Bow Information

05/18/2017 1:05 PM

have you never heard "Keep your eye on the ball?"

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#58
In reply to #56

Re: Cross Bow Information

05/18/2017 1:29 PM

"You'll shoot your eye out!"

Water rocket is intrinsically safe for forested area launch. Others not so much, and black powder might be a really bad idea, since those are known to spew molten powder and sparks badly (at least some of them).

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#66
In reply to #27

Re: Cross Bow Information

05/18/2017 11:19 PM

Mine was like this one, but bigger.

I used an igniter for a gas BBQ. I also used long threaded 6-32 machines screws in an arrangement where I could adjust the gap for the juiciest spark.

I had removable barrels so I could adjust the length and diameter for different "experiments" ..

Going at it again or in your case I might think about making the main chamber adjustable in size by using a large diameter coupling and pipe nipples of different lengths. .. getting the air/fuel mix and ignition correct may take a couple of tension filled go rounds, but once you've got the gremlins out it's amazingly satisfying to fire.. even with nothing in the barrel. (warning- residual gasses may become flammable some time later and scare the heck out of you and others if you give it a click for no reason while it's laying around.)

If I were you I'd go spend $50 and a couple hours making a proper potato gun to learn a little theory. ANY opportunity to do little R&D feasibility study that involves making a potato cannon should not be passed up. Think about it.

And report back if you do!

..oh.. Also run down to the fabric store for some of these to add weight to your findings..

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#39
In reply to #19

Re: Cross Bow Information

05/18/2017 10:02 AM

A friend (unnamed here) has an air cannon potato launcher, but it usually vaporizes the potato.

I suspect with the proper projectile, you could easily launch 1000 m, and still deploy a find Kevlar string.

My uncle used to have a device for launching "D" cells that used carbide, water, and a spark plug - magneto arrangement. You have to be careful with the drip feeding into the carbide chamber, that you don't over do it, and wind up purging the oxygen out of the charge zone. He could fire a "D" cell over a mile, apparently within a radius sufficiently near the neighbors cow herd to send them packing.

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#57
In reply to #19

Re: Cross Bow Information

05/18/2017 1:17 PM

This is pretty cool used in law enforcement for non-lethal attitude adjustment....

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#21

Re: Cross Bow Information

05/17/2017 11:58 PM

What about a double box Kite? If you use two lines to fly it off of the target, you can steer it to the far end and connect your pulls. You may need to do some tree climbing but you sure can carry the weight and cover the distance with good control.

I once flew a 4ft x 4ft double box with a 35mm camera underneath and it lifted it easily in a 20MPH wind. With two lines like a stunt kite it was steerable and in a 35MPH wind I could lean back into it at 45deg! It held ME up!

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#26
In reply to #21

Re: Cross Bow Information

05/18/2017 12:19 AM

Wouldn't the control of the kite become increasingly difficult as the line length increased?

Probably the cheapest solution if you could get it to work (but I forsee plenty of problems).

Dibs not being the one to have to go into the forest or down the gorge to collect the downed kite.

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#59
In reply to #21

Re: Cross Bow Information

05/18/2017 1:35 PM

I see what you are talking about:

two guys stradding the right of way of the overhead XMT lines, one control string each, kite downwind between them spooling out, and also carrying the primary stringer line.

Brilliant, now if we just knew about this jungle, and how many days in a row it remains becalmed...

I am back to thinking controlled balloon. Problem there is the same, unless you install a fan motor on it, to force it to move down range. Is it a drone if it is tethered? Will it still be prohibited?

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#31

Re: Cross Bow Information

05/18/2017 3:25 AM

What country does not allow drones in a forest but crossbows?

Which one is more dangerous to life and nature?

Must be lots of low flying planes above the forest to make these rules.

Who sees drones in forest anyway?

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#32
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Re: Cross Bow Information

05/18/2017 3:31 AM

Crossbows don't catch on fire...

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#45
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Re: Cross Bow Information

05/18/2017 10:45 AM

Hmm, drones normally do not either.

But I guess gunpowder is not an option then.

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#33

Re: Cross Bow Information

05/18/2017 4:10 AM

Almost everything is possible, but the sort of cross bow you probably need, is called a Catapulta if I remember correctly.

Anything a human can carry will never do it!!

The good point is that it can also fire steel/stone/lead balls (attached to the line of course) such distances, and could be fitted in the back of a pickup truck for mobility. See here:-

https://www.google.de/search?q=roman+ballista+jpg&rlz=1C1PRFI_enDE717DE717&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwiS7uPt6fjTAhUPfFAKHdn7CAIQsAQIJQ&biw=1242&bih=636

In the Royal Navy years ago, we used the "Costin gun line Rifle", which shot a steel rod, attached to the thinner line, many hundreds of yards, but 500 meters? Sorry no idea....but possibly. It had to work between when moving at speed, in even stormy weather.

It was based on a modified Lee Enfield .303 service rifle.

Are those pylons so high that you need 500 meters????

My personal take would be to use a rifle (even one with a worn barrel would work fine. Get some rods made (brass would probably do less damage) that fit "almost", between the rifling. several inches longer than the barrel, so "blow by" will not burn the attached line..

Blank cartridges of a type where you can vary the amount of propellant as needed. Ver accurate powder scales will be needed.

With plenty of good wadding to seal the gases and push the rod out at high speed, with minimum leakage.....

The thin line usually needs to be coiled down, in a lip-less basket, to give as little resistance as possible, though fishing line on a fixed spool reel I find attractive....

I would make tests without that line attached, and aim to achieve at least 750 meters before adding the complexity/weigh/resistance of the line.

Mount the gun very firmly and have a way of protecting yourself from accidents!

Rather than using modern smokeless powders in the cartridge, you might want to start with relatively slow burning high quality black powders. They will accelerate the rod slower/safer even if there is a big puff of smoke from it, you do not want to stress the barrel too much.

If you have a choice, pick a heavily built rifle with a cartridge of high volume (black powder is less powerful than modern ones), one with a long barrel, to allow more powder to burn effectively.

Start with small loads first to get an idea of possible range. Remember, a doubling of range, generally needs 4 x more explosive......as a crude guide...

Do the height tests (vertical) once you have the experience of the "distance" shots....

I don't know if nylon fishing line is adequate or not, but I do feel that it will snap if you try to use it on the reels, too much inertia. Start with stuff rated at at least 30 Kg. breaking strength. Learn to use correct nylon knots, as normal knots can reduce the line strength....dramatically. It usually breaks at the worst knot!!

It is smooth, which should reduce the air resistance considerably, by the way.

Having it on large fixed spool sea fishing reel, or similar, might work as the resistance is then relatively tiny (if the reel is " aimed" correctly), especially with the spool filled to max, as any angler knows! A short fishing rod may be of good use too, but

You will need an area large enough to allow recovery of missile easily, by sight at first, till you have the line attached. Plan for losing most of them I feel......

Observe stringent safety rules....cabin/dugout, eye and body armour if not.

Someone in say a moveable hut with thick walls as "spotter" maybe...

Don't do any of this in a "half hearted" maner, as it could be very dangerous.

Weight of rods to be be very exactly held to.....or your test values will be useless......

If the correct length of rod is too heavy, you might need to thin out the rod in the middle, reducing weight but leaving lengths at the top an bottom of the width of the "caliber" of course, for sealing and guidance of the rod. The front leave heavier than the rear I feel....

Theoretically, the rear part could even be a bullet, suitably drilled to accept the rod/tube? Careful rod insertion from the other end to find that hole. Maybe with a small area to fit the bore as guidance. Just an idea....no need to even glue them together!

The Catapulta is also effective, but dangerous, and not so portable!! And I feel, even more dangerous to the user, than the enemy!!

Enjoy!!

See here on this video, they are very happy with just over 300 meters from such a huge thing!!:-

Catapulta

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#49
In reply to #33

Re: Cross Bow Information

05/18/2017 11:33 AM

So he needs to rig up a Ballista so that he can fire it remotely. He might be able to hook himself up at the Renaissance Fair.

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#35

Re: Cross Bow Information

05/18/2017 8:48 AM

Have you looked into getting an exception for the "one-time-use" of a drone?

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#36

Re: Cross Bow Information

05/18/2017 9:03 AM

See this: https://en.wikipedia.org/wiki/Lyle_gun

"A line-throwing gun is a short-barreled cannon designed to fire a projectile attached to a rope to a boat or victim in distress"

"Lyle Gun could shoot the projectile about 700 yards (640 m)"

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#60
In reply to #36

Re: Cross Bow Information

05/18/2017 1:37 PM

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#61
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Re: Cross Bow Information

05/18/2017 1:59 PM

Oh yeah, that last 15 seconds made me chuckle. Gotta love that.

Thanks SE.

This video reminds me of my Dad who was a gunsmith/machinist/inventor and always seemed to be making things like steam engines, cannons, custom machinery etc. He also built many custom bolt action rifles, muzzleloader rifles and pistols, and a few odd experimental single shot pistols.

I learned a lot from him.

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#64
In reply to #61

Re: Cross Bow Information

05/18/2017 5:02 PM

Yeah that guy left in a hurry didn't he....lol I guess they used that as an anchor to keep the distance uniform,, somewhat.....

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#62
In reply to #60

Re: Cross Bow Information

05/18/2017 2:35 PM

Good videos, thanks for posting.

Particularly this one I feel, is pertinent to here:-

Line firing guns

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#65
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Re: Cross Bow Information

05/18/2017 8:20 PM

I really didn't need his plumber crack

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#72
In reply to #65

Re: Cross Bow Information

05/19/2017 8:56 AM

guess he never heard of Duluth Trading Co. plumber crack-less shirts.

I supposed a Frolicking Llama could teach him a lesson or two about the Hind-Lick maneuver.

His mother never told him to pull up his pants??

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#38

Re: Cross Bow Information

05/18/2017 9:36 AM

Every transmission line through forests that I've seen has the forest below it cleared so that maintenance can get access.

If you're going to eventually have to clear the forest below the lines to provide maintenance access, then do it now and you can walk your string to the next tower.

When it comes to crossing a gorge you would have line of sight for drone use and you may be able to get permission for drone use in that case.

To your point 2 where you say that access by foot or vehicles between towers in most areas has much limitations: - don't you have to create an access to the tower sites in order to construct the towers in the first place?

Once your first tower is in place then clear cutting your way to the next tower fixes your access and your line hoisting problems and you can sell the felled timber too, as you would then have a timber extraction route as well.

It sounds like you're in a nature park where restrictions are high but running transmission lines does require compromises and when I look at the footprint on the forest floor of clear cut paths that are cut below transmission lines for maintenance purposes, they are a miniscule percentage of the whole, and how are you planning to conduct maintenance if it's not by drone or helicopter when you don't have clear cut avenues below the transmission lines?

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#42
In reply to #38

Re: Cross Bow Information

05/18/2017 10:17 AM

The answer is in front of us. They should clear the forest in the right-of-way, sell the lumber, etc. In lieu of that, use a robot that can carry the pilot line across the spanned distance, either by climbing up and jumping from one tree to another, or when required, climbing down and up ravines. It might be a mess at first, but eventually the pilot line will be in the clear, and then you move forward.

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#43

Re: Cross Bow Information

05/18/2017 10:28 AM

I think you should contact PSE Archery and ask them. I have crossbows, both Barnett and one of them is the Ghost 410, which is one of the most powerful crossbows made. However PSE also makes a crossbow that is just as powerful but PSE also does other things with crossbows that the other manufacturers don't, they have a crossbow that is an attachment to an AR-15.

http://pse-archery.com/

It might be as simple as just using an attachment that is used for fishing, just change out the line.

But contact a manufacturer. They can tell you better than just an avid archer because the rest of us use them for archery and hunting, you're looking for a special application that they can better answer your questions.

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#44
In reply to #43

Re: Cross Bow Information

05/18/2017 10:34 AM

How and why would you put a crossbow on an AR-15 rail? Is this in addition to, or in lieu of the usual barrel?

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#47
In reply to #44

Re: Cross Bow Information

05/18/2017 11:27 AM

You break down the AR-15 and mount the crossbow on the AR-15 action. Probably designed for people that like to do both. It cuts down on storage space.

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#46

Re: Cross Bow Information

05/18/2017 11:16 AM

Why not use a maritime line gun?

http://www.navalcompany.com/

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#52
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Re: Cross Bow Information

05/18/2017 12:11 PM

That is a reliable tool, but the range appears about 1/3 of that needed.

Then there is this (only uses .22 blank):

still no where near the needed range for a single shot bridging over 500 meter.

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#55
In reply to #46

Re: Cross Bow Information

05/18/2017 1:03 PM

Thats quite near to what I envisioned, even to using black powder, which is to reduce the back kick and the acceleration of the rod.....The thick smoke tells a tale!!

Many thanks for your post!

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#53

Re: Cross Bow Information

05/18/2017 12:15 PM

It appears that a small rocket would work better than a crossbow.

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#54
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Re: Cross Bow Information

05/18/2017 12:19 PM

Now you just need a rocket that is not propelled by fire. I.E. a water rocket with a heater that instantly generates steam pressure, or maybe just use air pressure to shove the water out the nozzle.

I bet with 2000 psig air ballast above the water, that thing would really scoot. I would not want to be the fellow with the catch cone, though.

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#63

Re: Cross Bow Information

05/18/2017 3:46 PM

Whether using a rocket or launching a projectile with a giant cross bow, you should consider carrying the bulk of the line with the projectile to be spooled out behind.

Attempting to spool out from the launch point, causing more and more drag as it goes would make things much more difficult.

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#67

Re: Cross Bow Information

05/19/2017 12:04 AM

FYI

WWII German wire guided bombs used spools of piano wire to fly (steer) the bombs from aircraft up to 15kms to their targets (ships).

The reason I mention this is that it is useful to know the spools were hollow and fed from the inside, giving lower drag.

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#69
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Re: Cross Bow Information

05/19/2017 12:34 AM

The same as the TOW wire-guided anti-tank missile if I am not mistaken.

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#71
In reply to #67

Re: Cross Bow Information

05/19/2017 8:51 AM

Good call, and precisely to the heart of the conversation! I think they also used with some guided rocket munitions, although some of those were guided wirelessly using a "TV" monitor, and the bombardier used something like a joystick to control the flight.

(The Valkyries song plays in the background....fade to black.)

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#68

Re: Cross Bow Information

05/19/2017 12:14 AM

Consider using a kite. You could wait till the wind is favorable or there are also kites that allow a fair amount of control.

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#70

Re: Cross Bow Information

05/19/2017 8:40 AM

This line build is partially over the Himalayas and in the foothills and plains on both sides of the mountain range. Different regulations, different states and laws, and very different rules to western ideas, rules, and accepted practises. No drones are tolerated in any way, not even to own one. Two lads were jailed just last week for bringing 6 in from Dubai.

Cant even use an Erricson Skycrane over a dwelling area. So the chopper has occassional long routes to fly to drop of materials, another to drop of some crew. Choppers are not allowed to fly over houses, cattle, nor people here.

As for making access roads, HA Ha! As for clearing trees and bush, another Ha HA! Not allowed in any way whatsoever. The access road becomes a dwelling site over night and they can do that here. I have a line that a market has sprung up below the towers, and the only access is by foot and carrying each item we need for the lattice tower, including bolts by hand. the tower leg is about 1m from the shop owners counter and this is a busy market, full of people daily and I cant even get in to change insulators. And this is all live line refurbishment work, insulators, hardware and conductor and OPGW.

In the new line the towers are built around the trees where possible with little tree cutting as possible. That is the rules. And mid-span sag is 8.3m to the tallest tree along the route, so towers are taller than normal.

But thanks to all for the input and we now have a few ideas to work with and see what we can get away with using here without causing upset. Thank to all, IQ.

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#73
In reply to #70

Re: Cross Bow Information

05/19/2017 9:18 AM

IQ: one last idea to throw out there to you.

Have you considered falconry? One good trained Mongol bird, and you should be easily able to carry a threader line from one tower to the next with the operator launching the bird from one to the other operator waiting at next tower. The falcon arrives, perches on the operator's leather covered arm, and gets his treat, what could be simpler!

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#74
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Re: Cross Bow Information

05/19/2017 11:57 AM

They might not like it, but let's face it, they could never catch you....haha

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#76
In reply to #74

Re: Cross Bow Information

05/20/2017 5:06 AM

Would be most handy indeed and most convenient to get to the office as crossing a street here is Life and Death in any city.Road rules? They have never heard of them at all. It is a total free for all.

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#75
In reply to #73

Re: Cross Bow Information

05/20/2017 4:52 AM

This was a serious consideration as Black Kites are in abundance in all cities in India, and as most things like cows, one cannot utilise certain things. I.E. If I buy a cow and the seller stipulates I cannot slaughter it for food, all I can do is milk it. If I slaughter it for food it is a jail term. So one buys a cow and not bull!

But what has been offered here to date is helpful and was passed the aviation team to follow up with. The spud gun piping was sourced yesterday and we are in touch with the army and naval corp to see what they can assist with that is laying around unused in a store. I shall let you guys know what works and what we finalised on utilising.

I am trying to contact these to lads next week as a possible help.

http://www.audubon.org/news/in-india-two-brothers-are-saving-black-kites-surprising-foe-paper-kites

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#77
In reply to #75

Re: Cross Bow Information

05/21/2017 11:44 AM

Sounds like you're on your way. Another reminder for ventilation of the chamber between use or if non firing because it's​ too rich.

A ball valve/s and blower would speed things along and provide a consistent chamber condition. .. I found that after a few shots residue could gas into a very nice air/fuel mixture and remain so for hours. .. a safety switch might not be a bad idea.

Anything compressible (like a Nerf rocket) has been of little use.

I'm wondering about silly putty plugs? It (sp) can be home made in large batches and while it's soft when stationary, it should (under percussion) solidify into a hard weighted projectile capable of holding a string wad? (Maybe). I'd drop a large down the tube after a smaller potato and let them bond a few moments. if all goes well they will go the distance together.

As for the cone shaped thread bobbins above.. I'd pull the center tube out and allow them to unfurl from within as suggested to reduce friction.

Silly putty? Why not.. you already have a spuds gun.

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#81
In reply to #77

Re: Cross Bow Information

05/22/2017 10:29 AM

If they used combined electrolysis gas, no need to worry about lean/rich fuel ratio. Stoichiometric hydrogen/oxygen should fire every single time!

Just disconnect the gas hose between charging and firing, and move it away some distance.

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#82

Re: Cross Bow Information

05/22/2017 1:08 PM

One thing I considered today is a spear fishing gun. With a standard elasticated mechanism I was informed that 170m is achievable quite easily, so we are now hunting down a spear fishing gun with reel and an upgraded elastic firing mech' to trial. I think we will end up with an arsenal to trial in the coming weeks.

Cant rotate pic here, however, this was the last works in Ethiopia and I used a traction machine on the line to pull in ropes on the existing conductor, to restring new conductor, so that was an easy fix. (Across a gorge from tower to tower was approx 950m) The spot on the conductor is a traction machine weighing 48kg towing a rope and cradle block rollers fixed every 5m on the rope. This is all live-line at 220KV.

I shall feedback what worked and what didn't work on this new project. Thanks so far for the input. Cheers.

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#83

Re: Cross Bow Information

05/22/2017 1:27 PM

Hello IQ

I have been read this thread with great interest.

Your problem is one many of us face, in terms of constraints .

I would suggest a Balloon-Kite Hybrid [Possibly Blimp Shaped]

With 3 lines

1- the drag line [ it can be very light] which you will pull other lines across until you have your Trolley line in-place to carry your transmission lines.

2 - 2 Guide lines, Right and Left [I suggest Kevlar kite string] to guide the Hybrid to location.

I might I also suggest you attach a flashing LED light to it of the type used on bicycles

If you can have the drag line deployed from a spool on the Hybrid rather than drag it along so much the better.

Also as an alternative you can deploy secondary balloons to keep the line elevated if needed.

This has the advantage in that it will work is the lightest wind conditions and should be fairly cheap. You can probably use a modified advertising balloon.

Take a look at https://www.publiclab.org/wiki/kite-balloon- hybrid for some ideas

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#84
In reply to #83

Re: Cross Bow Information

05/22/2017 1:35 PM

I have to say, I was not at first envisioning live work in this manner. I suspect you will have all types of troubles if bumping into the live conductors in any manner.

Anything with guide lines off to the sides may not allow the "device" to approach the tower near enough for a "clean" lift into place.

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#85
In reply to #84

Re: Cross Bow Information

05/22/2017 1:43 PM

Hello

I thought this was a new installation?

If it was an existing system they could use one of the Cables to run a line dragger or some other form a trolley across.

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#86
In reply to #85

Re: Cross Bow Information

05/22/2017 1:47 PM

Live and under load? Are you serious? Maybe you are, what sort of materials. You want to go first, and grab the new line being dragged, once it reaches next tower?

Sounds pretty sparky to me. No thanks.

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#87
In reply to #86

Re: Cross Bow Information

05/22/2017 2:04 PM

It not some thing I recommend, But it is done

Working Hot: Life at 765 Kv

http://simson.net/ref/1988/IEEE_Working_Live.pdf

They can also Denergizer the line. To install a guide line.

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#89
In reply to #87

Re: Cross Bow Information

05/23/2017 9:07 AM

https://www.youtube.com/watch?v=t4faphX7thY

Looking to purchase these as by-pass lines for the existing lines over houses. Re-conduct the old towers by sections while the ERS towers take the load, then swing the ERS towers back to the original towers with a new conductor installed. Then move the ERS towers along the route to the next section. Very cool and nifty system but has a large footprint due to the guys and pricey. Around US $3.4m we need to budget for ERS towers only and about a week to train the crew on erection.

Now here is a cool toy:

https://www.youtube.com/watch?v=2h6UPMcy8-o

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#88
In reply to #86

Re: Cross Bow Information

05/23/2017 8:52 AM

Perfectly safe if done correctly and if the crew follows procedure. I have two projects here I am looking at that the conductor will be replaced live. 220kV at 2500A loading. First we need to replace a few towers and many foundations before new (HTLS) High Temp Low Sag conductor is replaced. I did one in RSA, upgrading an 88kV to 132kV, and all conductors were done live at 88kV until we swung the transformers over to 132kV and that was a 3 hour shut down for the droppers to the Tfx bushing connectors fixing.

It is actually safer than crossing a street in Delhi.

http://www.ameu.co.za/Portals/16/Conventions/Convention%202011/Papers/Live%20Line%20transmission%20line%20upgrade%20projects%20First%20in%20Africa%20P%20OHalloran%20Aug%202011%20rev%201.pdf

The LineMaster rig is cool to work with. The boom is insulated to lift three phases of the tower under live line, while insulators are changed and reconfigured for HTLS conductor. All remote controlled but very expensive.

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#92
In reply to #85

Re: Cross Bow Information

06/12/2017 1:23 PM

Brand new line and no existing conductor to use a traction machine on. The spud gun I do believe will work and carry the kevlar line to the next tower. We should know by next week how far it travels using a golf ball and tennis ball. My money is on the golf ball.

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#93
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Re: Cross Bow Information

06/13/2017 4:08 AM

If you're going with the golf ball, the longest drive ever recorded was 470m. Perhaps you just need to perfect your swing.

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#95
In reply to #92

Re: Cross Bow Information

06/13/2017 3:57 PM

In my experience the tennis ball is to soft and fuzzy allowing the explosive gas to blow by. A potato with a golf grown in the middle might be nice.

.. stubby spuds are nice because they don't cartwheel through the air.

.. Maybe a little canola oil for the barrel.

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#96
In reply to #95

Re: Cross Bow Information

06/13/2017 4:33 PM

We talkin' flinch fries or hashed browns?

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#97
In reply to #96

Re: Cross Bow Information

06/13/2017 10:26 PM

"...flinched fries or hashed browns...'

'...french flies or bashed browns...'?

'...launched-byes or fast browns.'?

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#101
In reply to #96

Re: Cross Bow Information

06/14/2017 7:01 PM

It depends on the wire you shoot through. 1/4" or 1/2" heavy chicken wire would make nice fries. A brick wall for smashed browns.

Crash n drown in oil boil. Salt and​ snack after the toil.

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#98
In reply to #95

Re: Cross Bow Information

06/13/2017 11:02 PM

I know with my black power rifle, I use patches soaked in bear grease or just veggie oil to make the seal. Which also insulates burning gases from the pilot line.

Wouldn't do much good to spend a lot of time in R&D only to smoke your pilot line before it leaves the barrel (Unless it's only compressed air) but patches will still give a better seal

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#99
In reply to #98

Re: Cross Bow Information

06/14/2017 11:28 AM

Patches? We don' need no stinkin' patches!

Well, yes, actually Arturo, you do need patches!

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#100
In reply to #98

Re: Cross Bow Information

06/14/2017 6:48 PM

Ha.. you just remindered me of the most dangerous projectile shot from the spud gun. It was stupid fun with an emphasis on stupid so I won't give details on the method. After some dangerous trial and error I got pretty good at launching mortars while simultaneously lighting the crazy fast wick. The fun was not knowing how far the mortar would fly before it went off and then what direction it would take when it did. The ones that would come back in your general direction were the most exciting.

Mind you these were very small mortars and there may have been a fifth on the fourth to provide some level of protection.

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#102
In reply to #100

Re: Cross Bow Information

06/15/2017 10:46 AM

Obligatory reminder....

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#103
In reply to #102

Re: Cross Bow Information

06/15/2017 12:04 PM

Man oh man, that looked like he was running with the right hand not much more than a bloody stump, the real blood loss not flowing yet. That is too bad, but yes, it serves as a reminder to all, to never do that.

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