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wyz2285
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Wed Feb 08, 2012 3:18 am

The top port has 5mm internal threads, to use it i would have to drill a hole in the middle of a 5mm bolt... No it won't work, the top port doesn't seal when energized.
CpTn_lAw wrote: :D "yay, me wanna make big multishot pnoob with 1000 psi foot pump compressor using diamond as main material. Do you think wet bread make good sealant? " :D
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POLAND_SPUD
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Wed Feb 08, 2012 6:19 am

are you sure?? what have you used to energize the coil? was it within its specs?
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wyz2285
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Wed Feb 08, 2012 6:37 am

I have the original coil that came from the valve.
CpTn_lAw wrote: :D "yay, me wanna make big multishot pnoob with 1000 psi foot pump compressor using diamond as main material. Do you think wet bread make good sealant? " :D
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Jimmy K
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Wed Feb 08, 2012 8:33 am

I had a similar problem with my 3 way valve - the 3/8" version. I called the company's tech support to try to get the thing to work. He ended up sending another valve overnight (he thought I was a company). So now I have 2. It turns out the first one wasn't leaking/broken. For the valve to work properly, I needed a minimum of 20 psi at the pressure port. Without pressure, the slide valve plunger thing can't move since the solenoid doesn't act directly upon the plunger. It directs air from the pressure port to push the plunger to the opposite position. So nothing will happen/it will leak if the pressure port is not hooked up and has pressure. Simply energizing the coil did nothing.

The internals of your valve and mine are identical. I bet your's operates in the same way.
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wyz2285
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Wed Feb 08, 2012 9:00 am

Thank you very much I´m going to try that :)
CpTn_lAw wrote: :D "yay, me wanna make big multishot pnoob with 1000 psi foot pump compressor using diamond as main material. Do you think wet bread make good sealant? " :D
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Question, does anyone have a co2 regulator, either aquarium or for tools (like the kobalt ones) that they are willing to sell? I am looking around, but I don't know if I can trust the ebay people, they say it will fit the paintball tanks, but the regulators don't look like they will. If anyone is willing to sell, how much do you want for it?
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Thu Feb 16, 2012 9:06 am

I'm trying to make a counter balanced valve, but I have a question: if the counter piston and the seal has the same area, will the valve re-seal or it will "dump" ? I will use a weak spring to keep it sealed
CpTn_lAw wrote: :D "yay, me wanna make big multishot pnoob with 1000 psi foot pump compressor using diamond as main material. Do you think wet bread make good sealant? " :D
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Crna Legija
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Fri Feb 17, 2012 12:05 am

If it perfectly balanced it will dump so yeah put a spring in there
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Fri Feb 17, 2012 3:09 am

I will put a spring, but will it still dump? it shouldn´t I think, but better make sure...
CpTn_lAw wrote: :D "yay, me wanna make big multishot pnoob with 1000 psi foot pump compressor using diamond as main material. Do you think wet bread make good sealant? " :D
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Fri Feb 17, 2012 5:02 am

No because it balanced the air's force is equal on both sides.
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Fri Feb 17, 2012 3:30 pm

good point
But anyway, lost my o-ring box :evil: can´t make it, so I made a traditional hammer valve with nylon seal :) 1000 psi no leaks.
CpTn_lAw wrote: :D "yay, me wanna make big multishot pnoob with 1000 psi foot pump compressor using diamond as main material. Do you think wet bread make good sealant? " :D
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spudamine
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Mon Feb 20, 2012 3:50 pm

A question about suppressors, I'm making a hybrid and want to make it as quiet as possible. For this I'm planning on a full length barrel shroud and can probably make it about 3 times the combined barrel and chamber volume. The barrel length is around 65cm and I will probably drill the last 10cm with holes. Will probably only be fired at 3X so unlikely that projectiles will go supersonic.
Question, should I leave the barrel shroud empty or stuff anything in it, and should I bother with baffles? I've read stuffing it with wire wool will make it more efficient but am reluctant to reduce air flow into it and take up valuable volume. Regarding the baffles it seems like a lot of extra effort for something that will probably not do much.
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Brian the brain
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Mon Feb 20, 2012 4:42 pm

Normally I would suggest foam.Normal for me means...pneumatic.
:D

In a combustion or hybrid however, that won't work.

is it in anyway possible for you to put a checkvalve in the supressor?
Something that would allow gas to fill it but then trap it?

A piece of bicycle inner tube over the barrel perhaps?
Or several sections of it, depending on the amount of holes it will be covering..

or perhaps a better idea is to put in two baffles , one in front and one behind the hole(s).
Then add holes to the rear one and springload a large washer onto the holes.
Air can pass through the rear baffle by blowing back the washer and springtension and pressure close it off trapping the gas.
At least that will be able to withstand high temperatures.

It is preferred not to make it 100% airtight, but rather to have it leak out the gas slowly..

This should reduce the report substantially, if the suppressor has a large enough volume.
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Mon Feb 20, 2012 4:49 pm

spudamine wrote:Question, should I leave the barrel shroud empty or stuff anything in it, and should I bother with baffles? I've read stuffing it with wire wool will make it more efficient but am reluctant to reduce air flow into it and take up valuable volume.
In terms of volume, you're only taking up a small fraction of the space using wire wool and there's plenty of spaces for the gasses to flow around, remember in a suppressor turbulence = good! The main reason for putting the wool though would be to absorb the heat from the gasses in order to reduce their pressure.

If you do take this route, don't use fine wool or it will ignite, and a good swabbing of lithium grease helps with the heat absorbtion.
Regarding the baffles it seems like a lot of extra effort for something that will probably not do much.
In my experience baffles are worth the effort and really not that much of a big deal if you get creative (and we know you are from previous builds ;))

Have you seen this? It's for firearms but relevant to hybrids, a little TL;DR but worth looking though: http://www.spudfiles.com/forums/suppres ... 18108.html
is it in anyway possible for you to put a checkvalve in the supressor?
Something that would allow gas to fill it but then trap it?
This is an interesting line of thought.

The best manifestation is the "captive piston" design where no gas at all escapes, but the physics of stopping the sabot is a bit of a challenge. A high flow check valve between the barrel porting and the suppressor chamber could be an attractive alternative.

Using "wipes" as brian suggested is effective in dampening sound, but from another thread:
I have done some experiments in the past, mainly using bicycle inner tube that would be perforated by the passage of the projectile at exit end of the suppressor, and they do have a significant effect when it comes to sound reduction, however there are two major downsides:

- they have a significant effect on power, particularly when used with "marginal" devices such as commercial CO<sub>2</sub> pistols.

- they have an even bigger effect on accuracy.

The Welrod pistol for example used wipes and was extremely effective, yet was intended to be used at "same room" range, so effective sound suppression was much more important than accuracy, and a reduction in power was also beneficial given the fact that the 9mm round was potentially supersonic.

The De Lisle Carbine of the same era was intended for a range of several hundred meteres, so accuracy was important, and fired the naturally subsonic 45 ACP round, and therefore didn't use wipes.
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JDP12
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Mon Feb 20, 2012 5:46 pm

JSR- question about the whole high pressure with one of those QEV valves.

if I just backed the original rubber pistons with a steel washer, do you think it would function fine, instead of making a whole new piston?
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