Air Cylinders
I’ve been contemplating having a go at making my own air rifle, the one thing that gives me pause is the air cylinder, we are dealing with a great deal of energy there.
I was thinking originally of using a talon bottle I have, but it does limit the designs somewhat.
but then I found that air-guns of Arizona is selling FX air cylinders 😀
you can get 148cc and 180cc air cylinders for what I think is a reasonable price, definitely worth the piece of mind.
they actually also sell the smaller extension so you really could get a pre-fabed air cylinder of the size you want 😯
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You do any hunting with your setup, or just target shooting?
sent u a pm. I am near Anniston also.
I did not get a PM???
waynej
sent u a pm. I am near Anniston also.
i was looking at online metals…and they rate the 304/316 .065″ tube at 2500 just like mac1…so im gonna play it safe and up that to the next size wich i belive is .83
if i had a hydraulic press or something so i could test the .065 tubes my self i would probably do that…but i dont…so .083 it is…
probably gonan order it from that cheap place i found…maybe i should write my local metal shop see if they have it and save some shipping
where are you in Al?
I am close to Anniston
Wow, check out the yield strength on Normalized 4340!!! Could make for some lightweight air cylinders.
i was at the metal supply to pick up some aluminum and stuff yesterday….its part of Admiral Metals…but they mostly just carry 6xxx aluminum and a few copper and brass rods…the store is intended for hobby guys …bought 9 pounds of alu…30$ compared to online metals..i was just astonished…
anyhow i asked if they could help me with tubing….
304/316 steel is exstremely expensive…like 40-50$…where 4130 is like 10$ ..they even found that a little weird…they are hopefully gonna call me today with options on tubing…as the little outlet aprently dont talk to the big warehouse…otherwise theres allways that other site i found…shipping aint too bad on 10 feet of 4130 and that should be able to last a while
have you asked any of the hydraulic tube supplyers of the presure rates , they usually have lots o books and charts that cover all stuff . and would be on top of what the tubing will do , not just a guess , the 2 supplyers i have are all over the info charts when i tell them what i do with it .
i assume the 304or 316 is a stailess ? don’t under estamate that stuff , it is way stroger the regular steel, close to 1.5x .
nope nothing build just yet….
i was looking at online metals…and they rate the 304/316 .065″ tube at 2500 just like mac1…so im gonna play it safe and up that to the next size wich i belive is .83
if i had a hydraulic press or something so i could test the .065 tubes my self i would probably do that…but i dont…so .083 it is…
probably gonan order it from that cheap place i found…maybe i should write my local metal shop see if they have it and save some shipping
but still no answer why Mac1 say max 2500 psi on his .125″ wall tubes…
and DAQ says 2200 psi in a .065 tube….
which make me nervous of getting something that thinwalled, without somekind of explanation
CYGNUS,
I beleive mac1 is 7/8 od, 3/4 id, actually .065 wall as said. DAQ 1″od 7/8 id .065 wall. larger dia tube w/ equivilant thickness requires reduction in working pressure. DAQ’s slightly larger dia. accounts for the reduced pressure recommendation.
Did you build a new tube yet Cyg? 😀
That link for the cheap 4130 is great. Thanks for posting it.
You are only looking for .875″ OD right? Check this page out. It is for hydraulic apps but, the pressure ratings would be the same right? List pressure with a design factor of 4 for 4130 .875 OD .083″ wall is 3900. Does that sound right?
http://ihservice.com/PDF’s/Tube%20Selection%20Chart.pdf
**The link is kinda crazy for some reason so just copy and paste. **
i figured out that on mcmaster.com….you can do a search for seamless tubing and then specify OD and the working pressure your intrested in
.65 tubing came up short with 2500 psi just like mac1 says…
the materiel selector selects 304 and 316 steel and not the 4130 that is suggested here though product 89895K78 or 89785K62
for pressure above 2500 it says .12″ which is uhmm quite a bit but is good 4600 psi …89895K79 or 89785K67 but quite expensive as well
if only they had something in between in seamless like .083 i bet that would land it at 3200 psi or so
onlinemetals.com has the .083″ tube in SS304 and rate it at 3500 psi
i found a cheap source of seamless tube in 4130 here http://www.aircraftspruce.com/catalog/mepages/4130tubing_un1.php
thoughts anyone ?
I’m sure there is probably a generic calculator out there that would work, just to lazy to go look 😀
5 seconds on Google:
http://www.engineersedge.com/thread_strength/thread_minimum_length_engagement.htm
anyone have the calculation for how many threads you’ll need to hold that plug for a given pressure? or a link to some place that does?
I’m sure there is probably a generic calculator out there that would work, just to lazy to go look 😀
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Target shooting and varmint hunting:)