MUTHA F’NG TANK!!!!!
New tank/valve from AF. Built a collar and using a grade III bolt in the hole, tank is held with magazines wrapped around it in the bottom of the vise… the hole in the valve body is elongating due to all the stress and the #*(*#&*$&$*( valve is still in there solidly. You guys used heat on this?? How much?? I don’t want to ruin the temper on the aluminum….
walt
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You guys should have payed attention to what Wok said I just took off my valve about a week ago to do a mod to it what I did is buy what they call a dodge collar or shaft collar they usually don’t sell them that big at hardware stores I went to a TSC which is a tractor parts store or Farm and Fleet get a collar with a 1 1/4 inch ID inside diameter slip it over the collar on the bottle take out the set screw and replace it with a hex head bolt grind the very end of it down to fit in the hole without threads snug it up the get a large pipe wrench it will come off and not hurt the collar on the air bottle at all!
Rowdy, to reinstall I stuck the .308 bolt back into the hole (bolt is now bent slightly) and use it as a handle to tighten. I only hand tighten all my valves and have NEVER had a leak. While under pressure they bind against the threads, so never any chance they will work loose or untwist. Hand tight will serve just fine.
walt
Just reading the thread here, I hope you didn’t install it back that tight or with the locking agent??? The first tnak I got years ago was like this. I hit mine with the propane torch for enough time so as to barely be able to hold my hand on the tank, the thing here is the aluminum wicks the heat away fast so you have to move quickly once you pull the heat sorce off the tank…
The freakin’ loctite274(red) they use has to be heated to release it… I used dielectric grease on the threads an O-ring since… I figure AF uses the 274 for insurance purposes only… They know full well you don’t need that with an O-ring seal…
I stuck a 5/16″ punch in the blind hole in the valve body while holding the tank in the vice with rubber jaw inserts and then soon as the heat came off the tank neck, I whacked the punch with a 3 pound hammer real solidly and that loosened the loctite and then I spun it off really quick beofre the loctite setup again… No real danger of messing up the tank, just don’t go cooling anything off once your through. Let all this cool off naturally would be best…
Thats my nickels worth, but its a day late and 95 cents short now that your through LOL… Sorry I didn’t read here sooner
Blod/Selph valve. At 3000 psi it goes 930fps, so around 82 fpe. Just doing some testing.
walt
A little careful work on the grinder and it looks fine except no more bluing… ran some paint on it and letting it dry right now.
walt
That is why you make the collar to slip over the valve.
😯 Nice, a shaped charge away from yourself, excellent idea!!! 😀
Which valve did you stick in there?
OK, I’m ready to repressurize the tank… here’s how I’m going to do it, just in case. I’m going to make sure I’m on the OTHER side of the heavy metal press…
Flashed the neck a couple seconds at a time with the propane torch (I don’t have a heat gun) and whacked away. No luck. Had to dig out the medium pipe wrench (no not the 3′ long one)… it came out grudgingly. Crap that was on tight. Now my valve body has tooth marks on it from the wrench 🙁
A little careful work on the grinder and it looks fine except no more bluing… ran some paint on it and letting it dry right now.
walt
Nope, because these tanks aren’t ever hydro’d.
😯 Thread lock, wouldn’t that complicate hydro testing in the future? 😯
Yep boiling water ought to do the trick 😀
Thanks, guys, will give it a go sometime today.
Sam, an interference or tight fit would respond well to your plan. But I suspect there is some loctite or thread binder from the factory. They respond to heat, but I can’t afford to heat this tank that high. Loss of temper in a pressure vessel is asking for major debilitating injuries or death. Things start to change temper state at around 400 deg F, so I should probably heat it to around boiling temp…
walt
Being left handed I tend to look at things screwy sometimes. Why not try cold? Take a bottle of rubbing alcohol, pour it into a big bowl and stick it in the freezer over night. Next day dunk just the valve into the alcohol for one minute. Might contract just enough. OR it may just be a dumb left handed idea 🙄
later
Heat and quick taps of the bolt with a small hammer will get the valve off and it will look as it did before it came off. Without marring the surface and without screwing up the bolt hole.
Per the spec sheet’s I checked Delrin (the seal material) has a melting point of around 350 F and can undergo intermittent temperatures of 300 F……
You don’t even need to heat it up that much, Mine wouldn’t even boil small water droplets.
Offcourse, if people want to seriously deform the bolt hole (and god know’s what else inside the valve) after reading how EASY and non destructive it can be then they can go right ahead.
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I found a drill bit sized so the shank fit the hole snugly. Heated a bit with a heat gun (torch would do), then gripped the tank between my legs and put the end of a piece of wood against the drill bit. A few sharp raps on the wood broke it loose and you could not tell it had been touched. I think this advise came from someone else here about a year ago.