Need Help - First Cannon

Boom! The classic potato gun harnesses the combustion of flammable vapor. Show us your combustion spud gun and discuss fuels, ratios, safety, ignition systems, tools, and more.
User avatar
tsb
Private 2
Private 2
Posts: 35
Joined: Mon Oct 08, 2007 8:58 pm
Location: Spudville

Thu Oct 11, 2007 1:32 am

@Ammo
Thanks for your sympathy, i appreciate it...

@Nova
Thanks too, nova, i never really liked my pa, and then when he was gone i missed him so much,

And yes i did have troubles with my cap, the cap went further then my spud, it got around 25m, and the spud got around 20m.
I am going to build a meter that measures the gas so i can get exactly 40cc everytime...


TSB
User avatar
tsb
Private 2
Private 2
Posts: 35
Joined: Mon Oct 08, 2007 8:58 pm
Location: Spudville

Thu Oct 11, 2007 2:43 am

Hey,
1. Does anyone know why my edit button isnt showing up? Is it happening to any of you guys?

2. Need HELP! I installed the chamber fan and hooked it up right, it's 12v and its wired to a 9v battery, i got my potatoe in, and it was a nice fit.
I then put 3 seconds, as usual, of the LPG gas. It got abit over 100m.

I then switched on the fan for 10-15 seconds. I put in a potatoe (nice fit).
I put some more fuel in. I activated the fan for 5 seconds. I shot. The potatoe went a whole, dun dun dar! 2m and the back cap fired off and snapped into 4 bits, the fan had minor damage wich i fixed in 2 seconds...

Help please.


Thanks in advance
TSB
We can often do more for other people by trying to correct our own faults than by trying to correct theirs.
Current Projects: Pneumatic Marble rifle
Status: Planning and Buying parts
Novacastrian
Staff Sergeant 2
Staff Sergeant 2
Posts: 1603
Joined: Sat Aug 11, 2007 6:59 pm
Been thanked: 1 time

Thu Oct 11, 2007 2:55 am

Your endcap is piss weak :lol: :lol: :lol:
You get more power from a fan setup :lol:
You my friend need a new gun!
There is some serious restiction to airflow in your current design- or you are stuffing those spuds in sooo tight that it blows up.
Try different looser fitting ammo. :P
America, the greatest gangster of all time. With 200 million odd foot soldiers at it's whim and call.
When you fill your car with refined oil remember that it has been paid for with blood and guts, some from your own countrymen, most not.
User avatar
Pete Zaria
Corporal 5
Corporal 5
Posts: 954
Joined: Fri Mar 31, 2006 6:04 pm
Location: Near Seattle, WA

Thu Oct 11, 2007 2:57 am

Which direction is your fan blowing and where is it positioned in the chamber?

It should be near the rear of the chamber ("behind" the spark gap) and pointing towards the barrel.

How tight was the back cap on? Do you have a replacement? :-p

I suspect your problem was the fan position and direction... let us know?

Peace,
Pete Zaria.
User avatar
tsb
Private 2
Private 2
Posts: 35
Joined: Mon Oct 08, 2007 8:58 pm
Location: Spudville

Thu Oct 11, 2007 3:01 am

If i get more power from a fan setup, why when i shot the first time it didnt do anything more than it usualy does.

Im using a 32mm barrel, is that to small??

Thanks
TBS
We can often do more for other people by trying to correct our own faults than by trying to correct theirs.
Current Projects: Pneumatic Marble rifle
Status: Planning and Buying parts
Novacastrian
Staff Sergeant 2
Staff Sergeant 2
Posts: 1603
Joined: Sat Aug 11, 2007 6:59 pm
Been thanked: 1 time

Thu Oct 11, 2007 3:06 am

I think that it is a little small (the barrel) but i think your current problems arise from not knowing how much fuel is being introduced into the chamber.
America, the greatest gangster of all time. With 200 million odd foot soldiers at it's whim and call.
When you fill your car with refined oil remember that it has been paid for with blood and guts, some from your own countrymen, most not.
User avatar
BigGrib
Corporal 2
Corporal 2
Posts: 652
Joined: Mon Oct 01, 2007 11:43 pm
Location: TriCities, WA
Contact:

Thu Oct 11, 2007 3:21 am

I definatley agree about your fuel meter situation. I recently rebuilt the chamber on mine and got everything setup perfect, pictures coming soon, but once I got my meter setup with the schrader valve injection and the chamber fan i have so much power. definantley get a meter setup
Yea, that's definitely going to get you at least a tazer.
<a href="">DONT TAZE ME BRO.. DONT TAZE ME... AHHHH</a>
facebook.com/biggrib
User avatar
tsb
Private 2
Private 2
Posts: 35
Joined: Mon Oct 08, 2007 8:58 pm
Location: Spudville

Thu Oct 11, 2007 3:26 am

@Pete
My fan is positioned at the rear of the chamber and is blowing air out towards the end of the chamber... And unfourtunaly i do not have a replacement :( Im getting one tomorow.

@Nova
I will pick up a large syringe and a bottle of butane...

Well ill upload some pics soon ( first i gotta take them, and find the cord to my camera )
We can often do more for other people by trying to correct our own faults than by trying to correct theirs.
Current Projects: Pneumatic Marble rifle
Status: Planning and Buying parts
Post Reply