The Behemoth revisited

[biggsauce]

Hey yall this is the last cannon I had built before the SGTC forum shutdown. Its the biggest cannon I've built, but theres always room for improvement

Its a coaxial barrel sealing piston valve. The piston is 2 3" endcaps with a rubber washer bolted to one end. It seals a 1.25" x 20' barrel, perfect for d cell batteries. The camber is 4" x 8' and is exhausted by a blowgun actuated 1" sprinkler valve.

on the trailer is a generator, compressor, and the days victim: a microwave

overall, it measures 24' and packs one hell of a punch

[Jared Haehnel]

Thats a nice cannon. What is it capable of distance wise and damage wise?

[Maniac]

Whoa that thing is amazing hope to see some damage soon. What do you pressurize it to.

[scottcrete]

better than what i built... nice job

[biggsauce]

thanks guys

as far as distance i really have no clue, but damage wise, it will puch a clean cookie cutterhole through 1.5" plywood at 60 psi. i also tried to puncture that comprssor tank you see on the trailer at 60 psi, but large dents is all it will manage. When i find the pics i'll post em. At 90 psi it put a nice hole in an old car doo though, ido remember that!

[Jared Haehnel]

Up it to 120 or 150 PSI and depending on what your using as a projectile I'm sure you'll put a round into a compressor tank...Plum Bobs make nice ammo for that...

[jackssmirkingrevenge]

I remember this one, when it comes to power bigger is always better

In this age of youtube, are there any videos handy for sharing?

[biggsauce]

I just might have to break this one out of storage to get some videos for you guys as i never took any when i was using it.

And Jared, i'm not too confident on taking the pressure up above 100 on those diaphram valves arent they rated for 115? i'm really not surem but if they are, then i'll just have to turn my regulator up a tad

and thanks for the plumbob idea, hadnt thought of that

what i had thought of trying was welding on a washer to the back of a 1" bolt and sharpening the end, but finding the time for all these projects just gets harder and harder

[Jared Haehnel]

100 on those diaphragm valves aren't they rated for 115?

It would depend on what valves you bought...you should be able to look it up online but I have a couple that are rated to 150 psi... and didn't pay more then 20 bucks as piece for them...

[jackssmirkingrevenge]

Most sprinkler valves I've seen are rated to 10 bar, roughly 150 psi, so I'd be comfortable taking it to that pressure - and on a launcher of this magnitude, a few extra psi translates into a substantial gain in muzzle energy *hint hint*

[biggsauce]

Ah alright, I believe its a watermaster? I really don't remember, but I'll have to look into that. What brand are those valves you mentioned?

[Jared Haehnel]

I bought Rain Bird I believe..basically the cheapest ones I could find that were rated to 150 PSI...I'm going to use them to bleed of the pilots on my 4 inch piston valves for the cannon I'm building...

[biggsauce]

Whoah 4"?

A barrel sealing tee type? That sounds like a nice project and the makes of one mighty pwerful cannon!

Shoot for the moon brother, literally!

[Jared Haehnel]

I my goal was to launch full soda cans a long long ways...its been a work in progress for a while... while the design is sound my income isn't...

That is one heck of a co-axial you've got probably the biggest I've seen any idea how fast does it sends a "d" cell?

[biggsauce]

Pretty darn fast! Honestly I dont know, I whish chronos were a tad cheaper. It has the full 20' to reach its muzzle velocity, and with the piston and plenty of air, I can only imagine. I have thought about the poor man's chrono with 2 sheets of paper a certain distance apart and measuring the time from when it passes throught the first sheet to the next, but I doubt I can get anything near reliable, or being able to hit a stopwatch that fast

i hear ya on the income, looking forward to seeing that beast!