I have heard many negative things about propane injected spud cannons usually to do with multiple misfires. I have already bought a lot of parts for the propane meter, but hearing all of the negatives, I'm having second thoughts of even building one. Has anyone built a really successful propane injected spud cannon and is completely satisfied with its performance???? If so, I could use any constructive ideas or tips please!! Are there any benifits of a propane injected cannon besides a general hairspray cannon??? Do they have more power??? Any info is greatly appreciated.
Thank You
Hans
Propane Injected Spud Cannon. Are They Worth Building???
They are much more reliable then a "spray and pray" gun. they will also be much stronger. please search first and use the wiki.
welcome to spudfiles.
welcome to spudfiles.
hansom72 wrote:I have heard many negative things about propane injected spud cannons usually to do with multiple misfires. I have already bought a lot of parts for the propane meter, but hearing all of the negatives, I'm having second thoughts of even building one. Has anyone built a really successful propane injected spud cannon and is completely satisfied with its performance???? If so, I could use any constructive ideas or tips please!! Are there any benifits of a propane injected cannon besides a general hairspray cannon??? Do they have more power??? Any info is greatly appreciated.
Thank You
Hans
Hairspray cannons have almost always too much or too less fuel. This makes the cannon unreliable: a big chance of misfires, loss of power and its also not easy to use.
Propane injected cannons have the following benefits:
-Faster, just a few ball valves open/close and your set.
-Powerful, the right fuel/air mix makes the most powerful shot
-Good fuel, pure propane burns better then hairspray
-Clean, hairspray clogs your cannon (and the spark gap electrodes), propane does not.
-Best benefit: No misfires. (if tweaked the right way)
how does a propane metered cannon have multiple misfires? it shouldn't if you do the math right first..
second off, please don't make multiple posts about the same topic- you have one pretty similar to this in SB15's cannon thread/.
second off, please don't make multiple posts about the same topic- you have one pretty similar to this in SB15's cannon thread/.
"Some say his pet elephant is pink, and that he has no understanding of "PG rated forum". All we know is, he's called JSR. "
I have one propane injected cannon, and it's never had a misfire.
Here it is.
They're a worthwhile investment, but for your own good, be careful about using them in or near inhabited areas. I ended up in quite a fiasco during my testing of the gun in the link (but it's all better now).
Here it is.
They're a worthwhile investment, but for your own good, be careful about using them in or near inhabited areas. I ended up in quite a fiasco during my testing of the gun in the link (but it's all better now).
Spudfiles' resident expert on all things that sail through the air at improbable speeds, trailing an incandescent wake of ionized air, dissociated polymers and metal oxides.
I want to here a storyI ended up in quite a fiasco during my testing of the gun in the link (but it's all better now).
http://www.spudfiles.com/forums/viewtop ... tml#176239pat123 wrote:I want to hear a story
Does that thing kinda look like a big cat to you?
I understand that you have to do the math right the first time, except that math is my worst subject. I found a formula for finding the correct propane meter, except that it is kind of over my head. Is there any way you could just use the same length chamber and same length metering pipe from a known successful gun? Is there any specs that someone could share with me? I plan on posting pictures of my two previous cannons on a weekend when i have more time. I also have some destruction pictures for everybody i will upload too. I think you will like it. My 2'' barrel cannon will put a dent in a tin shed from 50 yards away and go right through 3/4'' plywood from 15-20ft away. Anyways I am looking for length measurement for my chamber and a correct length metering pipe to go with it. If anyone is willing to help me, I would greatly appreciate it. Thanks.
Here's a simple method that only requires grade 7 level math skills:
Volume of chamber (length*pi*radius<sup>2</sup>)*0.042 = volume of propane needed. (V<sub>propane</sub>/V<sub>meter</sub>*14.7)+14.7=Required meter pressure in psig. This should be at least 30 psig, and no more than 90 or so.
We're not going to tell you exact measurements, as it isn't safe. Operating a potentially dangerous device that you don't understand isn't something we can allow you to do.
Volume of chamber (length*pi*radius<sup>2</sup>)*0.042 = volume of propane needed. (V<sub>propane</sub>/V<sub>meter</sub>*14.7)+14.7=Required meter pressure in psig. This should be at least 30 psig, and no more than 90 or so.
We're not going to tell you exact measurements, as it isn't safe. Operating a potentially dangerous device that you don't understand isn't something we can allow you to do.
Spudfiles' resident expert on all things that sail through the air at improbable speeds, trailing an incandescent wake of ionized air, dissociated polymers and metal oxides.
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i have a propane injected cannon, it works fantastic
do you plan on making your cannon from a "Straight" design, or an "Over-Under" design?
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“Happiness is the meaning and the purpose of life, the whole aim and end of human existence”
“Happiness is the meaning and the purpose of life, the whole aim and end of human existence”
Are they worth it? In a word, yes. Once you get the hang of it, you won't ever go back to a spray and pray.
Come on now, the math isn't that difficult...challenging at first yes, but a worthy expenditure of effort. See if you can find a math whiz friend to help step you through it....in any case YOU should calculate your own meter. That way YOU get to take credit for YOUR achievement.
Edit: Oh and propane burns into CO2 and water [and a tad bit of CO (carbon monoxide) depending on conditions and mix] leaving no residue....extremely clean fuel for spudding...
Come on now, the math isn't that difficult...challenging at first yes, but a worthy expenditure of effort. See if you can find a math whiz friend to help step you through it....in any case YOU should calculate your own meter. That way YOU get to take credit for YOUR achievement.
Edit: Oh and propane burns into CO2 and water [and a tad bit of CO (carbon monoxide) depending on conditions and mix] leaving no residue....extremely clean fuel for spudding...
I Planned on making a "Straight" design at first, then as i was surfing the internet, I kept seeing all of the "Over Under" designs and i really like those. What is the difference between the two??? I will probably end up making my first propane cannon a "Straight" cannon. Hopefully graduate up to my second with an "Over Under." Why do ya ask?
just wondering...and i suggest you stick with over under...its size is more compact and the difference it performance isn't really noticable without measuring...
Forum Rules - follow them or else!
“Happiness is the meaning and the purpose of life, the whole aim and end of human existence”
“Happiness is the meaning and the purpose of life, the whole aim and end of human existence”