some more reasons against the steel pipes...

Mobility, i want to beable to stuff this in the back of my truck... What do you think is more dangerious looking, steel pipe, or pvc?

Steel might resonate more, so it would be louder

I doubt I could buy a 3" threaded pipe, and cap, without getting carded, questioned, or arrested... PVC's alot less common in pipe bombs, for obvious reasons.



SO Beast, no sex, but alcohol, reckless endangerment, and dangerious opperations are fine???

~Nate

 

We made a Tennis ball launcher last week. And that sucker shoots ***** 700 feet. Using 120 psi of air.

 

I find that a timed charge of propane or MAPP gas works great. Something you do not want to experiment with is adding oxygen to the mixture. It will explode the gun. You will be picking little pieces of PVC out of your butt.

I find that a relatively large diameter combustion chamber and a long, relatively small diameter barrel works best. Of course, short barrels are great for noise, and that's got to be a consideration too.

 

(LOL) Now there's a sight I can live with out.

 

ick dude... just ick

For noise, I dont really want alot of it. Mines 3 foot long, 1 1/2" sch 40 pipe... Anybody know what size a marshmellow is? I googled it, and it looks to be 1"- 1 1/2"... anybody got one handy to measure (i dont)


Another coat of paint went on... w/e, i just want to fire it now.

~Nate

 

I apologize for butting into the young guys forum but saw this post in the General List (?) and thought you 'youngsters' might enjoy this link for tater launchers:

http://www.spudtech.com/default.asp

 

ACK, old dude alert, everybody, RUN!!!

Its fine, seriously. The reason I didnt post this in the general non auto, is because i dont want a "thats a waste of money" or "you might get hurt" or (better yet) "give me your name and address, im calling the cops"



Anyways, I did some testing tonight, and I'm having some problems with ignition of the combustion gasses.

The pledge worked before I glued it, but doesnt any more. Allthough the cans getting empty though, but i was still spraying pledge (not 100%propellant)

I got spark, but no ignition. I degassed the expansion chamber (with a fan) a few times... still nothing. With or without the end cap on

I tried pledge, hair spray, spray deoderant (suprizingly unflamabal), and spray paint (degassing&cleaning after each test)

I did get some carb cleaner, and that went... KAPOOF, and was pretty damn cool.

The ignitor is 6" from the end of the expantion chamber, and the the spark gaps the probes at <1/2" into the barrel.

This DID work well on pledge before I glued&painted it.
The end gap was around 3/4" before I cleaned and glued it... Didnt work afterwords, so I smacked it with a vice grips.

Any ideas?
~Nate

 

the best way for a spark is to get a spark plug and screw and glue it into the pvc. then go to you local TSC or farm and fleet and get a cattle or pig shocker. you get great spark. and is safe.

but if the ignitoin is not the prob then its the fuel you are using. try using starting fluid or hair spray, they work pretty good.
Mitch

 

I think if he tried that his new nick name would be NO Hands.

 

if you are trying to get a poof out of it with nothing in the barrel it dont normally do it. and the pledge bing almost gone could be the prob. when the redzone i use gets to about 1/8 of a can i chuck it becuase it is no good for launchin stuff. also i would try short sparys. something like 1.5-2 secs. also if you can get your hand in the chamber and spray from the top to the bottom it gets it all even in there for a better launch. i dont know if you can do it with the 3" chamber but it workes really good for mine with the 6" chamber.

 

Ohh and hold it upside down. your going to want mostly fumes in there.

Mitch

 

I didnt get flames either... No ignition

And I'm not using redzone, im using a 10oz knockoff brand...

I'll just use carb cleaner, and this was about a .5 second shot, and it went

~Nate

 

anybody know of anything else I can check, or am i stuck with carb cleaner?

Brake cleaner isnt flamabal either... oops

~Nate

 

like i said before, starting fluid or hair spray.

Mitch

 

I apologize for the comment earlier, but that's where the particles would end up.

I was having a couple problems with hair spray / carb cleaner, etc. What would happen, especially with the hair spray, is the ignition source would get wet and it would short out. Also, especially with the hair spray, the residue would tend to lock the threads on the cap. This made it especially hard to take back apart.

I prefer MAPP gas as a propellant. It is more sensitive than other fuels to the amount you put in though, but as far as I've seen it has the most power. A strong second is propane. One Bernz-o-matic and you're set for quite some time.