# Rope Cannon



## epanzella (Jul 18, 2021)

One of my favorite RC planes is tangled up in the top of a 100 foot tree. . That model plane is no longer available and I want it back. I decided to make a device to use black powder to launch a line up to the tree top to hopefully shake my plane loose. This is a total  _HAIL MARY _ but I can't just stand on the ground staring at my plane while doing nothing. I had an old hydraulic jack kicking around that I was just saving for stock and I turned that into a line launcher. Now if I can just get over the branch while NOT shooting a 3 inch hole in my plane this could work.


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## Reddinr (Jul 18, 2021)

I used a bow & arrow to do that years ago.  I lodged an arrow permanently in the tree on the first shot but got the plane down on the second shot (in a couple of pieces).  Good luck!   Stand waaay back in case something unexpected happens.


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## MrWhoopee (Jul 18, 2021)

A mini Lyle gun, I like it! 

OT: We acquired one of the real ones for our high school "spirit" crew. Solid cast brass barrel with a 3 in. bore about 30 in. long mounted on a steel platform. Paid $80 for it. We fired it whenever the team scored a touchdown. It only lasted one season before administration decided it wasn't a good idea. Can't believe they ever let us fire it at all.


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## RJSakowski (Jul 18, 2021)

Or you could use a drone to run a line up.  A lot more precise.  Use some light fishing line to pull a rope up.


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## epanzella (Jul 18, 2021)

RJSakowski said:


> Or you could use a drone to run a line up.  A lot more precise.  Use some light fishing line to pull a rope up.


This tree is thick with lots of branches around the plane. Very good chance of getting somebody's drone hung up there with my plane. I've had offers but I don't want to make this a bigger problem than it already is.


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## markba633csi (Jul 18, 2021)

How about a big hydrogen balloon to lift a piece of lightweight fishing line with a hook?  We used to use an old stainless fire extinguisher as a gas generator, with lye and aluminum foil. Gets hot, gotta be careful with lye too
Hydrogen gives more lift than helium- don't remember how much more
Welding shops have tanks of hydrogen also
-Mark
ps be careful with the "cannon" idea-


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## talvare (Jul 18, 2021)

I don't know how successful you will be with the cannon, but it should certainly be a lot of fun trying 
Good luck.

Ted


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## randyjaco (Jul 18, 2021)

I like the cannon, but you might want to check your local laws. You might have some problems with John Law


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## Nutfarmer (Jul 18, 2021)

For lower levels of putting a line in a tree , try what the aborists do. Find a small cloth bag ( like the ones part used to come in) ,fill it with sand ,and attach a line to it.  You should be able to clear a limb up to sixty or seventy feet with it. The plus side being when it comes down it won't hurt some one or the tree. We use this type of line thrower to install insect traps in the orchard. Hope you can retrieve your plane with no damage.


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## pontiac428 (Jul 18, 2021)

In my RC bag, I keep a spool bright colored of grading string and a wrist rocket slingshot.  I make those little monkey fists out of paracord and a ball bearing as a delivery system.  The key really is to shoot the string up there over a high branch and then shake the tree until your prize falls out.  Good luck, and be safe!


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## epanzella (Jul 18, 2021)

This plane is 100 ft up. I have to shake a 4 inch branch. I have a slingshot. I have a crossbow. They're not gonna do it without using fishing line and then trying to fish some real rope up there which means the fishing line has to come back down to the ground on the other side of the branch. . I've tried casting sinkers. They instantly get tangled and lost.  Guys in our club have been trying all these remedies for years without success except on the lowest hanging fruit.  I need to launch a 3/8 inch rope up into the treetops. Besides, What's more fun than doing it with a cannon?


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## tq60 (Jul 18, 2021)

A friend used a potato cannot launch electrical pull string about 100 ft over the top of the branch of a euculytus tree.

Used that to pull guy wire over branch to attach to bobcat to guide it down.

Sent from my SAMSUNG-SM-G930A using Tapatalk


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## Firstram (Jul 18, 2021)

I don't mean to be rude but I would not do that! I work special effects in the film industry and have seen quite a few destroyed mortars. The tubing looks heavy enough but the bottom will more than likely blow off with a charge large enough to reach your goal. Contained explosives are not to be underestimated!

When we build mortars we plug the tube with heavy plate thats beveled for 100% weld penetration. Then the bottom foot is welded on, usually 3/8" or thicker. I have seen them opened up like a frozen soup can! 

Use an air mortar or a spud gun, less likely to kill someone!


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## Shootymacshootface (Jul 18, 2021)

For RC boats we use a surf casting rod with a tennis ball. I dont see why this wouldn't work for you. I would probably tie a 3/4" hex nut on instead of the ball.
Definitely not as fun as what you have planned!


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## rwm (Jul 18, 2021)

I always thought this was WHY they made RC helicopters?



Robert


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## Dhal22 (Jul 18, 2021)

epanzella said:


> One of my favorite RC planes is tangled up in the top of a 100 foot tree. . That model plane is no longer available and I want it back. I decided to make a device to use black powder to launch a line up to the tree top to hopefully shake my plane loose. This is a total  _HAIL MARY _ but I can't just stand on the ground staring at my plane while doing nothing. I had an old hydraulic jack kicking around that I was just saving for stock and I turned that into a line launcher. Now if I can just get over the branch while NOT shooting a 3 inch hole in my plane this could work.



I probably own 50+ rc airplanes, they're all my favorite.  Watcha got in the tree?


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## epanzella (Jul 18, 2021)

Firstram said:


> I don't mean to be rude but I would not do that! I work special effects in the film industry and have seen quite a few destroyed mortars. The tubing looks heavy enough but the bottom will more than likely blow off with a charge large enough to reach your goal. Contained explosives are not to be underestimated!
> 
> When we build mortars we plug the tube with heavy plate thats beveled for 100% weld penetration. Then the bottom foot is welded on, usually 3/8" or thicker. I have seen them opened up like a frozen soup can!
> 
> Use an air mortar or a spud gun, less likely to kill someone!


The bottom is not welded. The bore stops 3/4" short of the bottom. Black powder will not blow this up.


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## epanzella (Jul 18, 2021)

Firstram said;
_I probably own 50+ rc airplanes, they're all my favorite. Watcha got in the tree?_

It's a Tech One Yak 3D. I love that plane!


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## KevinM (Jul 18, 2021)

Shootymacshootface said:


> For RC boats we use a surf casting rod with a tennis ball. I dont see why this wouldn't work for you. I would probably tie a 3/4" hex nut on instead of the ball.
> Definitely not as fun as what you have planned!


I have successfully retrieved RC planes this way and gained some knowledge along the way: 

When casting into trees with 2, 1/2" nuts and the line gets snagged.  Do not, repeat do not, pull the line really hard until it comes loose and the nuts hit you square in the chest.


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## RJSakowski (Jul 19, 2021)

I drilled a rubber ball and ran a 30" steel leader to it.  I use 30 lb. nylon braided line.  I can easily lob it some 50 - 60 ft but my accuracy stinks.  For use around the building, I will toss a 1/2 l. soft drink bottle filled with water.  Less chance of damaging the building.  If a bow and arrow are your weapon of choice, they make reels for bow fishing which pay out line smoothly.  There is a type of arrow called a flu flu which is used for hunting game in trees.  It typically has a blunt tip meant to stun game and the fletching is designed to limit the travel.


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## Janderso (Jul 19, 2021)

What could go wrong?


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## savarin (Jul 19, 2021)

make sure you video it


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## pontiac428 (Jul 19, 2021)

Here's a classic.  The "high angle crowd pleaser".


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## epanzella (Jul 19, 2021)

savarin said:


> make sure you video it


Didn't even think of that. I will!


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## epanzella (Jul 19, 2021)

I have a mixed bag on the rope cannon. Proof of concept is 100% with the line going right to the plane. The bad news is, despite moving the plane back and forth about 10 feet I could not shake it loose. I had to leave but I think if I could hook the branch just below the plane I could break it and release the plane. I had to leave for an appointment but maybe next time. I welded the cannon to a base plate and put a piece of angle iron underneath to square up the plate with my truck bed and make it repeatable. I also put a threaded rod on the other end to control elevation. I used the side rails of my truck bed as the gunsite. The system worked really well and I was within 20 feet of the plane right and left on the first shot but way too high. I started out at 90 grains of GOEX black powder by volume and ended up at 40 grains. The lighter load put the line carrier right over the top of the plane. If you look close you can see the plane right under the yellow line as it lands in the tree top. This was my eighth and final shot. Here's the video.


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## rwm (Jul 19, 2021)

That's freaking awesome
R


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## mmcmdl (Jul 19, 2021)

Janderso said:


> What could go wrong?


Absolutely nothing ! Here , hold my beer .


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## Firstram (Jul 19, 2021)

Well done!


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## Superburban (Jul 19, 2021)

triple post, sorry


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## Superburban (Jul 19, 2021)

distracted by the dog, and somehow posted in auto fire mode.


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## Shootymacshootface (Jul 20, 2021)

That was freaking awesome sir!


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## Eddyde (Jul 20, 2021)

Way cool!
What are the approximate dimensions of the cannon, bore, length, etc?


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## epanzella (Jul 20, 2021)

Eddyde said:


> Way cool!
> What are the approximate dimensions of the cannon, bore, length, etc?


The OD is about 1 7/8".  L = approx 8" .  Bore is 1" with a step down to 3/4" at the very bottom to form a powder pocket. Fuse hole is .125". Most of the dimensions were just convenient to the stock I had which was an old, defective, 12 ton hydraulic jack. The base plate is a hunk of an old
 rusty snow plow mount. I never throw away metal.


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## rwm (Jul 20, 2021)

I get it now. I did not initially get that you had a metal weight attached to the rope.
Such a great show! Thanks
Robert


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## epanzella (Jul 20, 2021)

rwm said:


> I always thought this was WHY they made RC helicopters?
> 
> View attachment 372609
> 
> Robert


WoW! Quite a chopper! You could probably bring me up there.


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## Flyinfool (Jul 20, 2021)

Try talking nice to the fire department about their ladder truck. They are often looking for places to practice .


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