I noticed if I have it screwed all the way on theres no air flow going out the switch.
Loosen it up a tiny bit and theres air flow.
I saw that old post btw.
I'm taking about vent holes though.
You let a battery pop in that tube and their will be plenty of airflow around the switch assembly. It's not an airtight pressure vessel.
It would vent instantly like a balloon to a neeedle.
Same reason there are no PV's with built in MP3 players.
There's not any becasue they didn't put any in it.
There's no rhyme or reason. There just isn't.
Lotsa MODS don't have vent holes and the PS line is one of those.
I don't know where you'd put them in this configuration. I don't think the tail cap would serve a purpose. They almost need to be on the sides and you would have to have some wiggle room inside the tube for expansion of the gas to get to the holes.
Vent holes would probably just turn it into a bottle rocket.
I think another cool way to allow gas expansion would be to flute the outside of the tube like a gun barrel so it would split (or fail) along the fluted lines. It would be a quicker release of gas and not form a jetting action....
It'd work well on stainless because stainless tends to tear or rip rather than fragment.
Now, if the batteries direct short and explode, I don't think anything is going to keep you from harm on that one.
No matter how you designed it there are some people that wouldn't like it for one reason or the other. People want them as small as possible with no wiggle room in the battery compartment and then complain about no venting / failure features.
If drilled / fluted / vented PV's are something you want, just look for a manufacturer that makes them and buy that one.
I don't have a single PV in my collection that's drilled and so far have never needed one.
This vent hole / battery thing is turning into the "what if scenario".
It's going on in the High End Flashlight mod arena also.
When you look at how many PV's and HV MOD flashlights are on the market and how few problems have been reported the numbers are as small as your chance of getting struck by lightning.
I can live with those odds.
People that can't should smoke cigarettes or use candles.
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