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Posted: Fri Apr 03, 2009 3:23 pm
by streetskater12345
I made a airsoft machine gun like this but it uses a soda bottle to hold the air and it has a plastic hose nozzle and is pvc not copper or metal. Does anyone know how to make some kind of HP tank that i can fill with a bike pump? The soda bottle can't hold a lot of psi and only lasts a little while. I only pump it up to 90psi so it doesn't explode. If anyone can help me on making a HP tank that would help thanks! :D

Posted: Sat Apr 04, 2009 6:56 pm
by roboman
streetskater12345 wrote:I made a airsoft machine gun like this but it uses a soda bottle to hold the air and it has a plastic hose nozzle and is pvc not copper or metal. Does anyone know how to make some kind of HP tank that i can fill with a bike pump? The soda bottle can't hold a lot of psi and only lasts a little while. I only pump it up to 90psi so it doesn't explode. If anyone can help me on making a HP tank that would help thanks! :D
It depends on your definition of "high pressure." If you want to be able to fill it up w/ a bike pump, then a 1' section of 1 1/2" sch. 40 PVC should suffice.

Posted: Sat Apr 11, 2009 3:21 pm
by streetskater12345
roboman wrote:
streetskater12345 wrote:I made a airsoft machine gun like this but it uses a soda bottle to hold the air and it has a plastic hose nozzle and is pvc not copper or metal. Does anyone know how to make some kind of HP tank that i can fill with a bike pump? The soda bottle can't hold a lot of psi and only lasts a little while. I only pump it up to 90psi so it doesn't explode. If anyone can help me on making a HP tank that would help thanks! :D
It depends on your definition of "high pressure." If you want to be able to fill it up w/ a bike pump, then a 1' section of 1 1/2" sch. 40 PVC should suffice.
by high pressure i mean around 400 psi will that work?

Posted: Sat Apr 11, 2009 3:32 pm
by Biopyro
No. PVC isn't usually good for such high pressures. I'd go for metal. Copper perhaps?

Posted: Sat Apr 11, 2009 8:59 pm
by c11man
pvc can hold high pressures...

you just have to stay below the maximum pressure and make sure the pipe is not damaged or too old/let in sun for too long.

but 1 1/2in sch 40 might work but it is above the pressure rating so it would probably expode because it is 70psi over the maximum pressure.

the highest i would want to go with it is 250psi if it was glue PROPERLY!

Posted: Sun Apr 12, 2009 1:50 am
by streetskater12345
c11man wrote:pvc can hold high pressures...

you just have to stay below the maximum pressure and make sure the pipe is not damaged or too old/let in sun for too long.

but 1 1/2in sch 40 might work but it is above the pressure rating so it would probably expode because it is 70psi over the maximum pressure.

the highest i would want to go with it is 250psi if it was glue PROPERLY!
so i can just use pvc? if i use pvc what is the highest i should pump it to? i wanna at least get about 250-300psi.

Posted: Sun Apr 12, 2009 3:44 am
by john bunsenburner
Either you are some kind of weight lifter or you have no clue how much 250psi are. No way in hell you will get anything over 200psi with a bike pump, The check valve or some other part would blow up, that is if you even manage to puth the handle down at over 200psi. If you need this kind of pressure you will have to resort to either a shock pump for low volume chambers, a scuba tank(or CO2) for larger chambers, or a self made stirrup pump which has a small bore and can therefore pump higher pressures.

Posted: Sun Apr 12, 2009 5:00 am
by Biopyro
You'll definately need a shock pump if you want to do this. How high you should pump to depends on the rating of the pipe. If it's rated to 150psi, you shouldn't tak it past that, if it's rated to 500psi (good luck!) then you have no problem. Look around and check some pressure ratings, but I'd still reccomend metal. The joints on PVC will hold longer than the pipe itself, so no need to worry about that, you just need pipe with the correct rating.

Perhaps you should also create a separate post for this?

Posted: Sun Apr 12, 2009 6:21 am
by Brian the brain
NOOOO! :shock:

Don't use PVC for this!
It's off topic but I think keeping people safe is more important than any other form of forum etiquette.

Use malleable iron fittings and pipe.
It;s not that expensive and it WILL keep you safe..

Back on topic:

This is what plinking is all about! Simple solution to get more shots.
Not the summit of spudgun design, just pure FUN!
Spare part guns usually are.

Posted: Sun Apr 12, 2009 8:15 am
by c11man
oh sorry didnt mean to give you the idea that you could get 250psi with a bike pump...

you might be able to get 200 if you have a pump with a small bore bike pump.

and with 3 posts what are you doing with 250psi?

Posted: Sun Apr 12, 2009 9:06 am
by Biopyro
Just because he has only 3 posts doesn't mean he shouldn't be using high pressure. Post count is not an indicator of experience for anything other than posting!
There are track pumps (Joe blow ace >$60) which will go to 250 psi, but they're expensive. Well worth it if you have the money though.

Brian - I thought that at first, but then I remembered that in the US it's quite normal to have small bore PVC rated past 16 bar.
Personally I'd definatley be using metal though.

Posted: Sun Apr 12, 2009 1:19 pm
by c11man
ok sorry about assuming the experience...

i know that when i had 3 posts i was a total noob, didnt even know what a hybrid was!

i would use metal too but i was just proving a point.

i know that i have a plinkler that uses 1 1/2 pvc (rated to 330) for a chamber and i want to upgrade it with a qev and use 250psi

Posted: Sun Apr 12, 2009 2:17 pm
by LCTChamp
i know that i have a plinkler that uses 1 1/2 pvc (rated to 330) for a chamber and i want to upgrade it with a qev and use 250psi
I would never take any sch. 40 pvc pipe to 250 psi. Even if it is half inch which is rated to 600psi. It isn't the fact that it can't handle the pressure. 99% of the time it probobaly will, but the one percent might be enough to seriously injur or kill you. If you use metal pipe you won't have any worries.

Posted: Sun Apr 12, 2009 2:59 pm
by c11man
well if you dont feel comfortable doing things then i wouldnt do them.

and yes i will look into metal chambers

Posted: Sun Apr 12, 2009 4:04 pm
by jrrdw
Thank you Biopyro for bringing this to my attention and your honesty!