Project: 10 gallon

[Technician1002]

With this gun rapid fire is the least of my concern.... lol I'll make that first shot count so I won't need to take many (if any) more. And I'll definatly know when it hit.

This gun has over 500cubic inches more volume than the "spudtech mega launcher" and also has over an inch extra effective porting area, meaning it WILL be effective lol.

That will be a serious cannon. One note of concern, the pivot support, would it need a brace to handle recoil forces? Low angle shots may stress the joints. With a heavier projectile, the force is strong. My cannon at less than 1/3 the size almost knocks me over when launching 20 oz bottles of gatoraid.

[thedeathofall]

I agree with what Tech says. Maybe you should try a metal housing and elbows. It will be more expensive but will be less likely to destroy itself.

[mobile chernobyl]

Yea TDOT - that's a good idea I think I'll just cut it up and make it all outta metal If this gun blows itself apart good riddance, however you probably can't see the support rib specifically for the "elbows and cross" clearly in the Cad drawing. Believe me - I've taken it into consideration.

I may just go with a different linkage design as well, I have a few idea's floating around in my head, it's just whether or not I feel like taking the time to make them lol. I just want to get this stupidly big monster outta my garage and to my friends house to start shooting through refrigerators again lol.

My next cannon will put more emphasis on metal, and will either be a floating piston Hybrid or higher pressure pneumatic like an SEAR avalauncher. Either that or I'm pursuing a detonation gun with like .75 to 1 inch walls and a smallish bore lol.

[thedeathofall]

Yea TDOA - that's a good idea I think I'll just cut it up and make it all outta metal

Okay, okay, so it wasn't my best idea ever.... still, it would suck to spend all this time and money, only to have it break on the third shot because of stress on a few joints which we warned you about. (I will say we told you so )

[mobile chernobyl]

TODA - Hey - I'm a mech engineering student, I know how to deal with stress This thing better not blow up, but just in case I'm more than prepared with a remote firing setup.

Here is the final iteration of the stand... Yea sorry I cheaped out and I just wanna get the thing done and move on! I went with a similar design to the good 'ol SWAT gun, only this ones a little more adjustable and... elegant? I drew it all myself lol (Solidworks FTW) - no Cad blocks, even the scissor jack which is almost an exact model of what I have so I know it'll work lol.






I purchased all the supplies to build it tonight, however will not start working on it till Thursday or maybe Sunday at the latest depending on how hungover I am after the concert on sat lol.

Damage shots will be a pleasing relief/end to this thread...

[boom_o_matic_2.0]

I really like the stand.

[mobile chernobyl]

yea I tried to keep it somewhat "aggressive" looking lol. It wont hit 45 degrees with the current jack pivot points and leverage ratio, but I dunno if I really wanna shoot this thing to it's full potential anyways lol (distance wise that is) at my current firing location... I'm not really sure how far it will go with a sabot'd piercing arrow round, and I don't wanna find out the hard way... So it's max angle as of now is more than enough for me, If i need more there's always shit to jam under the front legs... lol

[boom_o_matic_2.0]

could you maybe give a rough idea of how you made the stand? I'd really love to use that idea. its awesome

[mobile chernobyl]

It's just a solid model right now in solidworks, however I WILL be using that solid model to create the stand and since all my constraints (the gun which is made already, and the jack which I have) are corrected in the cad model post production - I have a pretty good Idea whether or not everything will physically work, and am pretty confident that I can just "cut stuff out" using printed dimensioned drawings from solidworks - and put it together like a lego set! lol

Another huge benefit of modeling something (or even thoroughly drawing it) is you can set up a list of procurement alot easier, and that way you can just buy stuff, and not mess around making up stuff in your head when your at the local "big box" home improvement store.

As far as how I made it? Learn solidworks, or obtain one of the free student versions they have now, and you too will learn the magic of a real parametric modeler. (not that alibre/rhino/sketch-up is bad, but solidworks is definatly a nice package to have on the comp, and one that will get you hired if you need a job and have experience in it)

[boom_o_matic_2.0]

is solidworks student version completely free or is it just a trial?

[mobile chernobyl]

it's free for 180 days I believe. By that time I'm sure you'll be able to "stumble" upon a longer copy, or you can just re-download the student version.

Just search for "solidworks student stimulus" or something like that, it's called there stimulus deal and it's basically a free download of the 2009 student version. 2009 is kinda cool, has a few compound features mine doesnt, but it also has the more bubbly vista-esk button's. It's still solidworks though, and if you look up tuturials you can even figure out how to run their single-part stress analysis program called "cosmosExpress". It's fun to get a rough idea if something will work... thats about it tho lol.

Just download it, and watch tutorials on Youtube - You'll love it.

[boom_o_matic_2.0]

I'll deff try it out. seems to be a great program. thanks alot man. so it dont have a briefing on how to use the program? if not its ok. I'll just do what you said and youtube the crap out of it. lol

[mobile chernobyl]

There are books on it, but I'm not aware of any included tutorials.

Youtube has alot of help tho, I use it for more complex features like surfacing ,compound lofting and what not, stuff you won't ever have to worry about with spudguns tho lol.

For drawing almost everything on a spud gun tube-wise you just draw the wall cross section and "extrude" it the length of the pipe you want. Fittings like 90's and 45's are a little more complicated, but you will find related tutorials on youtube.

Prolly the hardest thing I always run into in solidworks (or any 3D modeler for that matter) is relating "ok I want to make this shape, or feature, and I know how I want to do it, but what is it called in solidworks, and how does solidworks do it?" You need to think like the machine... be the machine... and you will slowly progress into a master draftsmen lol.

[Technician1002]

I guess I need to reply as I critisized the original stand. It looks great. Try to not make it too tall at the breech to keep recoil forces from imparting heavy rotational force. With the barrel strapped as shown to the chambers, is should not see much rotational forces on the elbows. I think the new design is fantastic. Can't wait to see the final result.

[mobile chernobyl]

Try to not make it too tall at the breech to keep recoil forces from imparting heavy rotational force.

lol it's hard with a 12 foot plus long cannon.

I tried to keep the pivot point low to the ground so as not to increase the moment arm too much when increasing the angle of the muzzle, but in the end I'll just limit the angle of the muzzle to control this... I can't really fire it at 45 degrees at my firing location anyways lol.

Oh and I got these pimp 4 pack of orange ratcheting straps for tying the tanks and barrel together on their blocks... go home depot.