12/12/06 Big Update - The Taternator II Aluminum Spud Gun

[Dumbascii]

Added this post just to draw attention to big update edited into the top of the original post.

[mark.f]

- Weather was cold, around 28 degrees F. I suspect that this robbed huge amounts of combustion pressure by limiting the theoretical adiabatic temperature.

Lower inital temperature actually leads to a higher molar count of reactants at atmospheric pressure, leading to a theoretically higher combustion pressure. You are not lowering the final combustion temperature that significantly by having the reactants at low temperature. So, I wouldn't worry about that, it's something else. Probably your tank pressure.

[drac]

Yeah, lower temperature would increase the density of the gasses if I remember chemistry correctly, so as Mark said, it may have been higher combustion pressure, although there would be a limit on it with cold weather.

EDIT: I also suggest that you post this on Spudtech. Join up and post it because there are many members who would shit themselves at this beast of a cannon!

[SpudStuff]

Did you have many parts already or buy them all for the 700 dollar price?

Every part was made by hand from raw stock.

Every part? Even the small brass fitings?

[drac]

Did you have many parts already or buy them all for the 700 dollar price?

Every part was made by hand from raw stock.

Every part? Even the small brass fitings?

Oh stop being nitpicky. It's an awesome cannon, stop being a sarcastic ass for once.

[GOLDLOKS76]

wow nice i love it is amazing i want it

[Brian the brain]

Amazing craftmanship!!
All I can think is:~WOW!!!

[Billy Bob]

Jesus 8) good work .. it looks evil awesome

Loud enough now to need hearing protection. Really makes your ears ring.

That must be a great feeling ! So it have to be !

What is MAPP i´ve never hear that before and find no informations in internet. Can you give me the chemical sign ?
Do you use pure O2 ? ( yellow bottle ? ) I have never seen a little O2 bottle like yours or is that not pure ?


Great work .... greetings from Europe.

[Dumbascii]

What is MAPP i´ve never hear that before and find no informations in internet . . . Great work .... greetings from Europe.

Here is a wiki entry about MAPP which is the yellow tank. I'm not sure about availability in europe, but since MAPP is a trademark of British Oxygen Corp (BOC), it is probably available. The oxygen tank is not pictured, but is a small green cylinder from a torch kit like this one.

[joannaardway]

Mapp is readily available over here in the UK. (Found it in my local hardware store).

In fact, it's barely more than propane for a bottle. Whereas, I understand that anyone in the US pays at least double, if not triple.

[turbohacker]

how much machine time do you have into that beast
I totaly agree with the guys, that thing is way cooler than the one on spudtech

[Dumbascii]

how much machine time do you have into that beast
I totaly agree with the guys, that thing is way cooler than the one on spudtech

It's hard to add up. I'm not a real machinist, so some parts were effed up and scrapped, some redesigned . . . Probably about 40 hours. To build a new one from scratch would probably take only 20 hours.

The spudtech SP9004 gun is smaller and of a different design, turned instead of milled. There's another turned gun that is much bigger and could probably compete with mine for extreme fuels and power capability:
http://forums.spudtech.com/topic.asp?TOPIC_ID=12971 it's really beautiful.

[beebs111]

you should mill a special penetrating projectile out of aluminum, or build some sort of dart made for distance

[Bluetooth]

Thats pretty funny. Your all discussing how to improve it and he has only posted 9 times !!

[thrasmussen]

I think it would be nice to have a breach block in the future.