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Ash gun?

Posted: Sat Mar 01, 2008 5:37 am
by wannabie
Ok, I just got a phone call and i have been told i have a great responsibility...
Recently my great grandma died and got cremated so my family decided they wanted to shoot them out from the top of a mountain. My mum told me i have to make a spud gun to shoot them out of...

Now I'm in need of some idea's.
I need to be able to carry the gun up a mountain and make sure the ashes don't come back towards us... The ashes will be smaller then a tennis ball, I'm not sure on the specifics yet.

I also need a special casing so the disperse after they are far enough away?

Any ideas?

I was thinking along the lines of a modded sprinkler valve with a one inch barrel.

Posted: Sat Mar 01, 2008 5:42 am
by Carlman
sorry to hear about your grandma.

well you dont exactly want loads of power in this, umm, strange use :D

a simple 1:1 modded sprinkler pneumatic would suffice : 24" * 1" chamber and same for barrel.

Posted: Sat Mar 01, 2008 6:24 am
by wannabie
Yeah I was thinking something along the lines of that, although Im not sure about the cartridge thing. I dont really want the ashes coming back...
I'll have to do some testing when i get back to my mums house and my bits and pieces.

Posted: Sat Mar 01, 2008 7:16 am
by socoj2
I would take a cardboard tube pack it really tight, and include a small powerfull explosive device *m-80*.

now light it 1 second before you fire the pnuematic.

Posted: Sat Mar 01, 2008 7:21 am
by wannabie
Have you by any chance not read the rules? BTW these are my great grandma's ashes, I don't think i want to go blowing them up anytime soon...

Posted: Sat Mar 01, 2008 8:25 am
by Jared Haehnel
Sorry to hear about your gram...

I think Carl man's got it make sure you fire the gun with the wind so the ashes are carried away from you and your family...

Try taking a paper cup and poking tons of holes in it placing the ashes in. Then place wadding down the barrel... that way the cup will dispense the ashes further away from you instead of right as the gun fires. If you don't it would kind of like sticking a cup of flour down the barrel. I don't think thats the effect you want...

As the cup flips around it will dispense and dump the ashes over a longer period of time... at least thats the idea...

Posted: Sat Mar 01, 2008 8:29 am
by jackssmirkingrevenge
This is by far the most curious use for a spudgun I've ever seen, I understand you want to make it a solemn occasion. It's difficult to put in a time delay that will burst a container of ashes in a reliable manner, the best idea would be a sabot fired along the wind direction.

Posted: Sat Mar 01, 2008 9:27 am
by Ragnarok
jackssmirkingrevenge wrote:This is by far the most curious use for a spudgun I've ever seen.
Ditto.

This could be a difficult task, achieving all your objectives in a manner that is suitably respectful.

Firstly, as Jack says, you need to launch along the wind direction. You really need a high drag sabot, which you might want to make a little more ceremonial than just a plastic cup with lengths of string hot glued to the back - but that's the kind of drag you'll need, because you need the sabot to slow down fast, because the ashes will do the same.

So very light, with lots of drag, but strong enough to withstand the launch.
A sabot that fell away petal-like would be best, but those are more suited for... erm... rather more solid projectiles.

It's quite a challenge you've got here. I would advise that you might do a few test launches of whatever design you create with a few ounces of flour first to make sure your results will be sufficently solemn - you hardly want to mess this up, as you'll remember it for the rest of your life. Best to do it as something you want to remember, rather than a thought that makes you want to hide under the nearest desk.

Results that would have been mildly annoying for a casual launcher would hardly be suitable here.

Posted: Sat Mar 01, 2008 9:45 am
by Jared Haehnel
Check out the foam sabots I make for my cannon they are highly adaptable to a variety of needs and they really work well at pealing away in a nice petal like fashion...

http://www.spudfiles.com/forums/biuldin ... 13270.html

Ragnarock is right you need to make sure what you do is a proven science I.e. lots of testing... before you do it

Posted: Sat Mar 01, 2008 9:48 am
by D_Hall
One thought that pops into my mind....

A paper tube that is sealed at *both* ends. This should provide for a clean acceleration through the barrel.

At the end of the barrel, a knife of sorts is mounted across the muzzle. This cuts the tube in half, blah blah blah.

Advantage: Clean acceleration.
Disadvantage: Very early deployment, but given the clean acceleration this may not be a problem.

Posted: Sat Mar 01, 2008 9:59 am
by SpudFarm
thats so sad!
i would have waited for a windy day and use a simple sabot and shoot it straight up. the fine dust will spread nice with the wind and get away from the people that are on the sight.

just don't mess that up you will break tougheter! try like 100 shots with fluor and sabots (different sabots) and find out what is the best for your use.


im so sorry about your grandma!

Posted: Sat Mar 01, 2008 10:02 am
by rcman50166
Personally I would use a rocket. I think they are much more ceremonial than a gun. Model rocket engines come with a parachute charge that can easily be used as a media ejection system. If you are interested in how to make one let me know. I've done hundreds of high power launches with multiple applications, including dispensal units for things like fire works and tracking smoke. Technically, the top end of a rocket is a potential spud gun so posting here isn't off topic.

Posted: Sat Mar 01, 2008 10:22 am
by jackssmirkingrevenge
You could always tie the projectile to a length of string (tied securely to the launcher) that would tear it open and disperse the ashes a set distance from the muzzle.

Posted: Sat Mar 01, 2008 10:22 am
by Counterstriker
Thats a wierd design.. do you have any time limits.. like when you have to be done.

Posted: Sat Mar 01, 2008 10:42 am
by STHORNE
definitely pneumatic with a 1" sprinkler valve. for the barrel size, i would sick with 1-1.5".

for the design of the shell with the ash in it, i drew up a sketch of what i think would be best if you wanted it to disperse about 20-30 yards away from you (gun being at a low psi with a small chamber)
_______________________________________________________________
Image
Image

the end of the bag should be tied somewhat loose so it has a chance to implode, allowing the ashes to disperse. The end of the bag should also be facing the muzzle of the barrel, not the chamber of the gun. and just a layer or two of plastic wrap (saran wrap) should do the trick, but too much and the shell won't implode.

hope i helped 8)
--sthorne