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Posted: Thu May 07, 2009 8:28 am
by psycix
At the OP:
The downside of those exhaust silencers is that they are made for normal pneumatic applications, meaning the pressure rating is usually about 8-12 bar.
While this is a fair pressure for a normal spudgun, I'm afraid that blowing out 30 bar through these things wont do them good...

Posted: Thu May 07, 2009 8:43 am
by POLAND_SPUD
@ rag
I'd spend forever if I had a fridge compressor, singular.
Imagenahh..... mine fill this to 100 psi in 10 minutes

it's made form 7 meters of 1.5" steel pipe


also keep in mind that you can't pump your gun while aiming or loading it... but with a fridge compressor you can

Posted: Thu May 07, 2009 8:57 am
by SubsonicSpud
POLAND_SPUD wrote:@ rag
I'd spend forever if I had a fridge compressor, singular.
Imagenahh..... mine fill this to 100 psi in 10 minutes

it's made form 7 meters of 1.5" steel pipe


also keep in mind that you can't pump your gun while aiming or loading it... but with a fridge compressor you can
:shock:
You need to feed you're air chamber, It is looking a bit skinny :lol:

Posted: Thu May 07, 2009 9:26 am
by LeMaudit
As for you're second post, you may not need something that big. It just depends how quiet you want it. Here is what I used on a copper Coax gun of 10mm bore with a much larger chamber than you have described
Thanks for the advises. Lots of fun to come :-D

Posted: Thu May 07, 2009 9:53 am
by jackssmirkingrevenge
LeMaudit wrote:If you have at hand some good links about DIY silencers please share.
Have a look :) it's for firearms but really the same principles apply to airgun silencers when it comes to baffles and construction.

Posted: Thu May 07, 2009 11:05 am
by psycix
Fridge compressors fill things quite fast. Sure, pumping like crazy may go faster, but I can just sit back and relax, watching the pressure gage going up.

Poland_spud, you should do something with that pipe, really!

Posted: Thu May 07, 2009 11:41 am
by POLAND_SPUD
@psycix
I still have at least one 8 meter lenght of the same size and a couple of other sizes too

well I was considering to build a simple HP burst disk gun with it but since I wouldn't have time to and place to fire it I think I'll still use it as an air reservoir


you should consider building something like this yourself... just turn the compressor on and go for a smoke and a cup of coffee.. when you get back you'll have it at 300 psi...

BTW
I am buying a nice 220V fan (looks like a computer fun but it's bigger) for my fridge


@at least I'll pretend that I am not going off topic :wink:
has any one tried building a gun with barrel volume the same as chamber volume X pressure ??

Posted: Thu May 07, 2009 11:46 am
by LeMaudit
Have a look Smile it's for firearms but really the same principles apply to airgun silencers when it comes to baffles and construction.
Again quite an interesting link! There's so many interesting things in the forums to read and watch, I feel like a rat in a maze intoxicated with a strong dose of PCP.

Thanks!

Posted: Thu May 07, 2009 2:49 pm
by Ragnarok
LeMaudit wrote:There's so many interesting things in the forums to read and watch, I feel like a rat in a maze intoxicated with a strong dose of PCP.
Actually, on that note, you might be interested in this Spudwiki page, because it's full of interesting links.
POLAND_SPUD wrote:nahh..... mine fills this to 100 psi in 10 minutes
it's made from 7 meters of 1.5" steel pipe
Well, at that rate, I'd be waiting half an hour for it to fill the reservoir to the pressure I'd need to fire off one 6 shot magazine.
And that would be from a "hot" fill. If I were doing a "cold start", then I could add quite a lot more time.
also keep in mind that you can't pump your gun while aiming or loading it... but with a fridge compressor you can
That's a bit like saying "It's hard to knit while cycling, but if you're the passenger in a car that's stuck in the middle of a traffic jam, it'll be easy." At least I'm getting to my destination on my bike, even if I have to do the knitting before or after my trip.
And yes, I can knit, before you ask.

I might not be able to pump while aiming or loading, but I'm actually losing far more time in the second case.
Loading will take a minute & a manual pump fill will be about 5 minutes of pumping - 6 minutes total. Loading takes place at the same time as a 30 minute compressor fill - 30 minutes total.

Sure, if the compressor could do the work in just a minute or so more than pumping, it would be worth it. Here, it really isn't, unless I can get multiple parallel pumps.
Four, at minimum. And then I've got to start wondering about where I keep that many pumps.

Posted: Thu May 07, 2009 3:05 pm
by LeMaudit
Actually, on that note, you might be interested in this Spudwiki page, because it's full of interesting links.
That's mean! :twisted:
But you know that, don't you?


Now I feel like a flabbergasted rat :toothy7:

Posted: Thu May 07, 2009 3:46 pm
by Ragnarok
LeMaudit wrote:That's mean!
That it might be, but I didn't make that page so that no-one ever uses it. :tongue3:

Posted: Thu May 07, 2009 4:02 pm
by POLAND_SPUD
Loading will take a minute & a manual pump fill will be about 5 minutes of pumping - 6 minutes total. Loading takes place at the same time as a 30 minute compressor fill - 30 minutes total.
I don't remember accurate dimensions but the tank is at least 9L

that's about 14 times the volume of the gun... mind you that heal is/was completely inefiecient as far as chamber volume is concerned - in other words it was an overkill - something made specifically to maximise power

I don't get it.... if pumping takes 5 minutes and loading 1 minute... how come it's faster than the compressor??

you could either load the gun and fill it in less than 5 minutes or just switch the compressor on half an hour before you shoot and then keep it running

Am I missing something ??

lol I just wanted to quote it again because I find your presentation of facts very uhmmm... amusing
Loading takes place at the same time as a 30 minute compressor fill - 30 minutes total.
would anyone sane wait 30 minutes to fire the gun ?? LOL besides you can just turn it on and do something else then get back and start shoting right away...
and what's the point in stating that it would thake 30 minutes to fire one shot if you can use air pumped-in two days earlier??

Posted: Thu May 07, 2009 6:19 pm
by psycix
@thread hijack
Uhg only 9L?! Then my reservoir (the Tnak) is about the same.
~10L fire extinguisher which I fill to 450 psi in 10-15 minutes with my fridge compressor.
Is that fast enough for you rag?

I also fill my QEV gun with ~600 cc air up to 450psi within a minute. Fridge compressors are NOT slow!

Though it does get very very hot after filling up the tnak three times in a row, and the heat capacity of the heavy thing is enormous, taking a lot of time to cool down.

Posted: Thu May 07, 2009 6:29 pm
by SubsonicSpud
gees, 15 mins to fill up a 10l tank. Get an air con compressor, they will fill a 10l tank to 550psi in 4-5 mins

Posted: Fri May 08, 2009 5:51 am
by psycix
If I can find one for free, then sure, but for now I'll have to stick with fridgy.
Aren't they also heavier n stuff?