Airsoft Canada
www.jsairsoft.com

Go Back   Airsoft Canada > Information Center > Newbie Tank
Home Forums Register Gallery FAQ Calendar
Retailers Community News/Info International Retailers IRC Today's Posts

Supressor filling

:

Newbie Tank

Reply
 
Thread Tools Search this Thread
Old March 5th, 2009, 22:25   #1
xtylertyx
 
Join Date: Jan 2009
Location: Canada, NB
Supressor filling

I am making a supressor for a NBB gun that i'm running on propane and was wondering what is a good filling to muffle the report. I figured I would post it here cuz it doesnt really fit into any of the other forums.
xtylertyx is offline   Reply With Quote
Old March 5th, 2009, 22:31   #2
Styrak
 
Styrak's Avatar
 
Join Date: Jan 2007
Location: Saskatoon, SK
Send a message via MSN to Styrak
Foam. Or foam-ish like material with lots of holes/airspace.
__________________

Airsoft Sales and Repair/Upgrade Services
Styrak is offline   Reply With Quote
Old March 5th, 2009, 22:39   #3
arman
 
arman's Avatar
 
Join Date: Nov 2006
Location: Windsor, Ont.
here i just took a pic of the inside of my supressor its soft foam

__________________

playing with my kid!
arman is offline   Reply With Quote
Old March 5th, 2009, 23:55   #4
arcanuck
 
arcanuck's Avatar
 
Join Date: Sep 2008
Location: Bilingual People's Republic of Neu Braunsweig
Depending on how well you want it to work, the filling to use will depend on the sound absorbent material's NRC and what frequencies you want to remove. The suppressor's internal volume will be a major deciding factor in how much can be used and also in determining the volume's Fs (resonant frequency) and second high order Fs. The suppressor will also amplify these sounds and can defeat the purpose, partial reason to why most are not super effective.

Last edited by arcanuck; March 6th, 2009 at 00:21..
arcanuck is offline   Reply With Quote
Old March 6th, 2009, 00:02   #5
L473ncy
 
L473ncy's Avatar
 
Join Date: Oct 2004
Location: 11-30-24-1W5
Cough cough. Manufacturing certain devices....
__________________
ಠ_ಠLess QQ more Pew Pew
READY TO >> RACE
L473ncy is offline   Reply With Quote
Old March 6th, 2009, 00:21   #6
CDN_Stalker
Official ASC Bladesmith
 
CDN_Stalker's Avatar
 
Join Date: Jul 2003
Location: Ottawa, Ont.
Send a message via MSN to CDN_Stalker
Quote:
Originally Posted by arcanuck View Post
Depending on how well you want it to work, the filling to use will depend on the sound absorbent material's NRC and what frequencies you want to remove. The suppressor's internal volume will be a major deciding factor in how much can be used and also in determining the volume's Fs (resonant frequency) and second high order Fs, the suppressor will also amplify these sounds and can defeat the purpose.
Wanker nerd. Lol.

Do what I do, get copper pipe foam insulation from a hardware store, cut into 1/2" slices, then take half of them and cut the thickness down to 1/4" or so. Alternate the slices, thick and thin, this creates foam baffles within the suppressor. Cut each to the right size to fit snugly (after expanded) into the tube, and use a barrel or a rod to press all into the outer shell of the suppressor. Literally what you want is vertical surfaces for the gas and the report to hit, isn't so much just open cell foam to absorb it, you need to have obstructions.
CDN_Stalker is offline   Reply With Quote
Old March 6th, 2009, 01:05   #7
arcanuck
 
arcanuck's Avatar
 
Join Date: Sep 2008
Location: Bilingual People's Republic of Neu Braunsweig
Quote:
Originally Posted by CDN_Stalker View Post
Wanker nerd. Lol.

Do what I do, get copper pipe foam insulation from a hardware store, cut into 1/2" slices, then take half of them and cut the thickness down to 1/4" or so. Alternate the slices, thick and thin, this creates foam baffles within the suppressor. Cut each to the right size to fit snugly (after expanded) into the tube, and use a barrel or a rod to press all into the outer shell of the suppressor. Literally what you want is vertical surfaces for the gas and the report to hit, isn't so much just open cell foam to absorb it, you need to have obstructions.
Actually there are a couple real reasons for using solid baffles, one is to create a series of chambers with high enough resonating frequencies that the damping material can absorb or otherwise nullify this acoustic energy and convert it to heat over the relevant bandwidth. The size of these chambers has to be tailored to the projectile bore diameter and barrel length, rather than having sound bouncing around randomly in these aforementioned chambers. The second is to form a seal as good as practical, forcing the expanding gasses to fill the cavities and in turn lower the pressure present at the muzzle; most suppressors will have a preliminary chamber to aid in this. Though it will not matter in Airsoft, it also relieves some of the pressure from the baffles to extend service life.

Again the lack of design knowledge and how to implement it properly keeps individuals from being successful in adequate attenuation, but that is a good thing I suppose since we don't want people building real ones either. So I guess if someone wants to change the sound and maybe lower the report a bit, foam will work.

Last edited by arcanuck; March 6th, 2009 at 01:38..
arcanuck is offline   Reply With Quote
Old March 6th, 2009, 11:13   #8
xtylertyx
 
Join Date: Jan 2009
Location: Canada, NB
Should I pack the filling tight? Or leave it loose with extra airspace? Or fill up all the space, without squishing anything?
thanks
xtylertyx is offline   Reply With Quote
Old March 6th, 2009, 11:35   #9
CDN_Stalker
Official ASC Bladesmith
 
CDN_Stalker's Avatar
 
Join Date: Jul 2003
Location: Ottawa, Ont.
Send a message via MSN to CDN_Stalker
Tight enough to stay in place and not shift, loose enough to not have it get pressed into the BB's path.

Quote:
Originally Posted by arcanuck View Post
Actually there are a couple real reasons for using solid baffles, one is to create a series of chambers with high enough resonating frequencies that the damping material can absorb or otherwise nullify this acoustic energy and convert it to heat over the relevant bandwidth. The size of these chambers has to be tailored to the projectile bore diameter and barrel length, rather than having sound bouncing around randomly in these aforementioned chambers. The second is to form a seal as good as practical, forcing the expanding gasses to fill the cavities and in turn lower the pressure present at the muzzle; most suppressors will have a preliminary chamber to aid in this. Though it will not matter in Airsoft, it also relieves some of the pressure from the baffles to extend service life.

Again the lack of design knowledge and how to implement it properly keeps individuals from being successful in adequate attenuation, but that is a good thing I suppose since we don't want people building real ones either. So I guess if someone wants to change the sound and maybe lower the report a bit, foam will work.
That's a bit much, comparing airsoft suppressors to the real steel ones. Lol, show off.
CDN_Stalker is offline   Reply With Quote
Old March 6th, 2009, 11:44   #10
FOX_111
Le Roi des poissons d'avril
 
FOX_111's Avatar
 
Join Date: Dec 2003
Location: Terrebonne, Québec
Quote:
Originally Posted by L473ncy View Post
Cough cough. Manufacturing certain devices....
cough cough... not real steel... cough... would by silly to try for real steel... cough...

I'm off getting cough sirup.
__________________

Vérificateur d'âge: Terrebonne
FOX_111 is offline   Reply With Quote
Old March 6th, 2009, 11:52   #11
m102404
Tys
 
m102404's Avatar
 
Join Date: Apr 2006
Location: Toronto
3M scrub pads
m102404 is offline   Reply With Quote
ReplyTop


Go Back   Airsoft Canada > Information Center > Newbie Tank

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Airsoft Canada
www.jsairsoft.com

All times are GMT -4. The time now is 01:52.


Powered by vBulletin® Version 3.8.10
Copyright ©2000 - 2017, vBulletin Solutions, Inc.