Well this little giant is at least 2 years in the making. Here is the original thread to prove it - http://www.spudfiles.com/forums/project ... 15399.html . College can mess with your hobby schedule but alas - It's complete!
What started as this
evolved into this
and finally was fabricated into this
And this pic gives you a better idea of it's scale!
The cannon was dubbed "10 gallon" originally because the chamber volume was to be appx 10 gallons of air. I splurged a little later on and it is now appx 11 gallons of air. Originally the air tanks were to be 6 feet long, and now they are 7 feet long.
Primary ammo will be 20-24oz soda bottle's filled with whatever may end up in them. Also soda can's fit with a very light layer of wadding, the same goes for the 16.9oz water bottles that are ever so common these days.
The cannon uses a 4" cross where the normal "Tee" would be on all the t-valve cannons. This allows me to draw air in from twin straddling air tanks instead of one big air tank.
The valve is pretty much your typical piston valve, Only it's a hearty 3 full inches of porting. To make it I started with two 3" to 2" bell reducers, cut down quit a bit to reduce the overall length - Then for the sealing surface I used a trimmed down Suction Cup pick up device like they sell at Harbor Freight for $3 and it works GREAT! It's about 4.25" in diameter originally, and is made of a decent durometer rubber that is designed specifically for sealing in air (or creating a vacuum), so I thought hey why not? I took my time in fabricating it and ended up with this.
Piston weight came to around 1lb 4oz. To provide a sufficient bumper for this (a major concern of mine, as my last "large cannon" failed catastrophically due to a faulty insufficient bumper) I ended up using two 1" pieces of radiator hose for a car - with different sized slits in each piece to allow a "progressive" bumper effect.
Now this cannon weighs almost 150lbs or more (havent put it on a scale yet - haven't found a big enough "bathroom scale" lol). To allow myself to adjust the angle of firing this beast, I decided right away I WASN'T going to jamb stuff underneath the front of the cannon like oh so many people on here doing - mainly because I wasn't looking to lift all the heft of this beast every time I wanted to change the angle.
To solve this - I purchased a scissor jack like the kind they put in cars for changing spare tires.
Which I later modified into this to allow mounting points to attach it to the frame.
The pivot, lifting arm, and scissor jack are all best seen in action in this picture
So there you have it - from imagination - to completion... all in 2 years! I was able to draw this complete cannon up in SolidWorks, a CAD program and from there I was able to see what would work - and what wouldn't before I ever assembled anything. I will now work on painting it, and recording damage shots!
Posted: Sat Jun 20, 2009 10:53 am
by mobile chernobyl
First Carnage video
[youtube][/youtube]
First outing's planned ammo:
Of course we have the large supply of 20oz soda bottles, and 16.9 oz water bottles.
Then we have some canned food and other random containers I got from good ol Ollie's bargain outlet lol
Then we step it up to the more aggressive concrete filled 20oz soda bottles with fletched shafts for better "accuracy"
Then we get to the fletched 1" pvc arrows with the nosed filled with concrete for better balance - these are for distance testing. We also have the 3/4" metal piping with 1foot of 5/8" allthread and three 5/8" nuts up front for sheer weight and balance, and then they will be grinded to a point for penetrating ammo! they will be fletched as well.
HEAVY OLD SUUUUUPPPPER STRONG metal filing cabinet, the kind they used to issue as temporary bomb blast guards or so it seems. This thing seriously was built 10X stronger than any filling cabinet I have ever seen.
The concrete filled bottles, and the pvc darts with concrete in the tips.
And the venerable Mac 'N Beef. @ 69 cents it was cheep ammo and gave a whole new meaning to "fast food"
Damage shots
Bureau from the front
Bureau from the top (the top when its sitting on the feet like normal)
Old file cabinet from the back (cement filled bottle penetrated sideways)
Filing cabinet from the side (wayyy thicker metal on the side of this beast) Nothing really penetrated, but the concrete bottles did dent the hell out of it and the metal penetrating arrows kinda penetrated even though they hit almost completely sideways
Microwave from the back (cranberry sauce can just about penetrated)
Microwave from the front (Vienna sausage blew threw the front door and ballooned out the inside of it)
And the reason the shooting ended early
The piston front separated from it's shaft at the spot weld performed by the original manufacturer (that's right, my Tig weld connecting the shaft to the all-thread held up fine!!!)
A close up of the failure. I will be using a solid piece of all thread through the whole thing next time to avoid this, and that way I won't have to rely on the weld performed stock. This thing was only meant to hold a mild suction to pick up glass sheet, not 80psi differential over 7.36 sq inches lol - that equals about 590 pounds of force on the poor thing!!
[youtube][/youtube]
Posted: Sat Jun 20, 2009 10:59 am
by MountainousDew
mobile chernobyl wrote:Spot reserved for Damage Pics/Vids
When will they be available to see and watch...
We planned a play-date today.
Awesome cannon as you know. I've been watching the other topic for a long time and seeing it come together has inspired me to build one for myself, but maybe smaller...
Posted: Sat Jun 20, 2009 11:07 am
by mobile chernobyl
MountainousDew wrote:
mobile chernobyl wrote:Spot reserved for Damage Pics/Vids
When will they be available to see and watch...
We planned a play-date today.
Awesome cannon as you know. I've been watching the other topic for a long time and seeing it come together has inspired me to build one for myself, but maybe smaller...
The damage vid's and pics should start next week, next weekend I've got a bike race pretty far away, so no shooting will be done then, So it may take a little while till I get any quality shooting time at a place I can use full power and penetrating projectiles.
I had planned on using today as a "fun day" but it turned out to be stormy and miserable... lame. Perhaps I will make my 3" sch40 barrel, and some pykrete ammo and penetrating rounds for the next shooting date.
Oh well the hard part is done - It is made lol.
Thanks for the kind regards, go build yourself a big cannon, but just make sure you have a place to shoot it, and you can transport it first lol
Posted: Sat Jun 20, 2009 11:21 am
by MountainousDew
Mine will only be about 5 feet long, but with a design similar to yours.
-Cross instead of a Tee for piston housing.
-Two 18 inch long chambers.
-2.5 SDR sch 21 barrel.
-And one kick@ss stand! (Mix of yours and Joel's Mega Launcher)
And I have a big trailer that my family uses to transport our ATVs and Dirtbikes...
Posted: Sat Jun 20, 2009 11:26 am
by Carlman
HOLY SHIT!!!
*cough cough, erkrrrmmm*
Umm dont know what to say, hows about...that is one Mother F'ing nice gun!
Hurry up and shoot something for christs sake!
Posted: Sat Jun 20, 2009 12:12 pm
by jeepkahn
Nice peashooter there kiddo... BTW, what type of racing do you do, and what region...
Posted: Sat Jun 20, 2009 12:53 pm
by mobile chernobyl
I mainly do DH MTB anymore. I guess with the new classes I'm a Cat 1- to Cat 2 racer (basically the old 19-29 "Expert" class).
I race primarily Mid-Atlantic area, WV being the lowest state, and VT being the highest state I travel to.
Posted: Sat Jun 20, 2009 12:56 pm
by MountainousDew
West Virginia! That's where I live! Yayyy!
Sorry, to get off topic...
Posted: Sat Jun 20, 2009 5:48 pm
by mark.f
+20 INTERNETS TO mobile chernobyl!!!
Seriously, the detail you've put into such a huge beast one wouldn't imagine required such detail is astounding. The scissor jack is a very nice touch (even if I would've opted for pneumatics/hydraulics ), and will really reduce some of the strain from your shooting sessions, although maybe not time...
Very good design, and even better finished product. Good work!
EDIT: also off-topic, but nice lawn...
Posted: Sat Jun 20, 2009 7:43 pm
by mobile chernobyl
Thanks for the internets! lol
I was seriously considering a longer stroke hydraulic ram from the mighty harbor freight, but they are slow to extend, where as the scissor jack isn't, allowing me to put it at max inclination alot faster if need be lol.
I also was trying to get a 1.5" to 2" bore by 12-18inch stroke pnuematic cylinder, but that wouldn't have had the balls to lift this thing now that I have it built and realize the leverage ratio in person. Keep in mind I typically only have 100PSI on hand at any volume, since I didn't want to use an HPA setup for just a pneumatic ram lol. 100PSI times even a 2" bore cylinder would only result in 600 lb's of lifting force.
I wouldn't doubt if there's over 750lbs at that point due to all the weight being forward of the wheels, and the high leverage ratio I created by only using a stroke of 11.5" inches on the jack to move the barrel tip over 6 feet
just a rough estimation - if all the weight is forward of the rear wheels - for sure - and the cannon weighs around 125lbs. My leverage ratio would be (barrel travel divided by scissor jack travel) 72"/11.5" = 6.25"ish. That means the jack must lift (leverage ratio times weight forward of pivot point) 6.25 X 125lbs = 781lbs. Now that was QUICK AND DIRTY, and not precise, but it does give you an idea of how much it could actually be lifting.
Oh and the lawn cut mention thanks will go to my mom. She's into nice lawns lol.
Posted: Sat Jun 20, 2009 7:45 pm
by Hotwired
Intimidating ^^
Considered capping off the ends of the wooden stand?
Posted: Sat Jun 20, 2009 7:45 pm
by starman
Nice and beastly!!! Congrats on its completion Mobile.
I must say though, I think the sissor jack implementation is beautiful. I've considered using one before but not in such an elegant way. You know, if you had a little bigger wheels and trailer axle on the rear, you could just about install a hitch on that front ground point, hook it up to a ball and tow that baby.
Sumpin' to think about... Now let see some damage.
Posted: Sat Jun 20, 2009 7:52 pm
by mobile chernobyl
starman wrote:Nice and beastly!!! Congrats on its completion Mobile.
I must say though, I think the sissor jack implementation is beautiful. I've considered using one before but not in such an elegant way. You know, if you had a little bigger wheels and trailer axle on the rear, you could just about install a hitch on that front ground point, hook it up to a ball and tow that baby.
Sumpin' to think about... Now let see some damage.
for the longest time I had been working on a howitzer trailer like the 105mm'
s design. I would have made it too, but I got ancy and just made a wood one, because I didn't really feel like spending that much more on this project lol.
Hotwired - Capping off the ends? do explain further
Posted: Sat Jun 20, 2009 8:11 pm
by thedeathofall
Nice!! I'm glad you finally finished it. Maybe later, when you have free time, you can design a different trailer/carriage.