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Modding a fire extinguisher
Posted: Fri May 21, 2010 7:51 pm
by Gun Freak
Are there any tutorials for modding a fire extinghuisher into an airtank? I have four of them laying around for no reason, and I need a backpack airtank for my bbmg in airsoft wars. I plan to use two of the fire extinguishers. Yes, I searched.
Posted: Fri May 21, 2010 7:54 pm
by Marffy
I believe it just depends on the tank you have. They all have different threads. good luck finding a tutorial tho.. You're going to be real stealthy with them big red tanks an your back.
FIRST POST
Posted: Fri May 21, 2010 7:56 pm
by Lockednloaded
I just finished my fire extinguisher tank for my semi-auto, i could show it to you if you want. I just jb welded a 3/4" nipple into mine and it has held 300 psi without leakage
Posted: Fri May 21, 2010 7:59 pm
by Technician1002
May I suggest unscrewing the valve and replacing it with an adapter to reduce the tank neck to fit an air manifold that includes;
1 Fill Schrader
2 Pop off safety
3 Hose qucik connect
4 Pressure Gauge
Posted: Fri May 21, 2010 8:02 pm
by Gun Freak
Thanks everyone, and LnL if it isn't too much trouble, yes please. Maybe I can find a place to discharge it then I will find out the threads that are one it. I don't plan to be stealthy in my airsoft wars... They're gonna be in a backpack anyways
Posted: Fri May 21, 2010 8:09 pm
by Crna Legija
i have a 1l FE that i use for a tank it has threads that are just a bit bigger than 1/2 inch, so i just epoxyed a 1/2inch nipple in to it works fine at 350and held from 3hr. just let the epoxy dry for 2 days
Posted: Fri May 21, 2010 8:11 pm
by Lockednloaded
no problem gun freak, i have some low quality web cam pics, but they'll give you the general idea.
Posted: Fri May 21, 2010 8:15 pm
by Gun Freak
Ok so I should be set using them at 200 psi, as that is the highest my bike pump can go, and high enough for a bbmg. I dont want to get a regulator, so I'm just gonna use quick bursts, saving air and bb's.
Thanks for the pic LnL, my tank looks like it has a 3/4 thread connection on it, but I can't be sure till I get the nozzle off.
Posted: Fri May 21, 2010 8:19 pm
by Lockednloaded
it probably will not have perfect threads, i have gone through 3 and none had normal threads, so to glue it in, get a pipe nipple close to the diameter, not a close one, and not a full inch one. cover the top threads with masking tape and cover the bottom with epoxy/jb weld. put it in and balance the bottle upside down. this will let the glue spread into the threads, and it will make sure the nipple is straight
Posted: Fri May 21, 2010 8:22 pm
by Gun Freak
Alright thanks for the help, I'll keep you updated.
Posted: Fri May 21, 2010 8:24 pm
by Lockednloaded
just make sure you have a pressure rated FE. mine said on the label that it was filled to 300 psi, tested to 760
Posted: Fri May 21, 2010 8:25 pm
by Gun Freak
Alright, I'm pretty sure it said tested to 300, not going near that anyway.
Posted: Sun May 23, 2010 7:42 am
by metalmeltr
I would recomened brazing the fitting into the fire extinguiser if you have a torch to do so.
Posted: Sun May 23, 2010 8:21 am
by boyntonstu
If it is aluminum as is my oxygen cylinder, I threaded over the Metric threads using s 3/4' tap.
the hardest part was fabricating a strap wrench the twist the cylinder while the tap was held in a vice.
I have designed a homemade strap wrench that will fit any size cylinder and that will not slip with all my weight torquing a breaker bar with a pipe extension.
Hint; Stretch a latex glove onto the cylinder for friction.
Posted: Sun May 23, 2010 9:57 am
by Gun Freak
metalmeltr wrote:I would recomened brazing the fitting into the fire extinguiser if you have a torch to do so.
You mean like to melt the outside of it where the bushing/nipple goes into the neck?
If it is aluminum as is my oxygen cylinder, I threaded over the Metric threads using s 3/4' tap.
the hardest part was fabricating a strap wrench the twist the cylinder while the tap was held in a vice.
I have designed a homemade strap wrench that will fit any size cylinder and that will not slip with all my weight torquing a breaker bar with a pipe extension.
Hint; Stretch a latex glove onto the cylinder for friction.
I will definately try to tap over it if I can find a 3/4 tap, I don't own any taps, maybe a neighbor does though. It is an aluminum cylinder, tested to 360 psi, filled to 120.
Thanks for the help guys.