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Sealing a hole in an air tube.
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Author:  EdLena [ Wed Oct 23, 2019 6:01 am ]
Post subject:  Sealing a hole in an air tube.
I drilled a hole (1/16") in an air tube to install a regulator. Now, if possible I'd like to change the hole location to accommodate a larger plenum.
I was thinking of attaching a shaped steel patch, say the size of a dime to the inside of the hole with silicone adhesive.
Has anyone sealed a hole like this?
Ed.
Author:  leadslinger [ Wed Oct 23, 2019 7:11 am ]
Post subject:  Re: Sealing a hole in an air tube.
Probably need something like JB weld. I wouldn't think silicone would handle the pressures, of HPA.
Author:  Gippeto [ Wed Oct 23, 2019 9:49 am ]
Post subject:  Re: Sealing a hole in an air tube.
With something low pressure (<200psi)...sure, solder on a patch.

With a pcp tube? Gluing on a patch just strikes me as a really dumb thing to do. You created a weak spot by drilling, which wasn't a problem before because that area wasn't pressurized and subject to hoop stress.

A spool with an oring on either side would seal it up and be safe, but it'll cost you some volume.

People get hurt when they do mickey mouse type sh!t...please don't.

Al
Author:  EdLena [ Wed Oct 23, 2019 10:08 am ]
Post subject:  Re: Sealing a hole in an air tube.
Thanks Al, I agree with what you said. I was just waiting for someone to confirm my fears. Now I can forget that nonsense.
Ed.
Author:  Chevota [ Wed Oct 23, 2019 6:09 pm ]
Post subject:  Re: Sealing a hole in an air tube.
Assuming it's a typical 3Kpsi gun, and therefore rather thick; I'd tap the hole and thread in a screw. I'd find the smallest possible, like #2 or whatever fits best. Then I guess use JB Weld or Loctite 569 on it, but I'd imagine a variety of sealers/loctite would work. Once done and sanded down it'll be almost as if it never happened.
I would also smooth the inside edge of the hole so when push your valve or whatever past it it won't cut the O-ring. That may be tricky but it's doable.
But yea, the patch thing is a bad ideal unless the patch was fairly thick, but my first thought was; how are you going to get your valve in/out? I guess out the back? Some guns you can't do that, but maybe most you can? Of those you can I'm guessing it's not as easy as out the front? Maybe in your case it's no biggie? Either way it would bug the crap outta me to have a hole and a patch. The ground flush screw would bug me too, but not nearly as bad.
If it's a low pressure gun, like CO2, I'd likely still drill/tap but I may weld it. You can weld the thicker high pressure tube too, but considering the pressure, which already makes me uncomfortable, I'd be worried about stress cracking. I'm willing to bet the odds of that are ultra slim, but still...
Reminds me of a shotgun I have that has a thinner chamber wall than usual so I won't shoot full pressure loads outta it. I'm sure it's safe but I look at it and think 14000psi w/ my face inches behind it. Pass.... Come to think of it it's barely thicker than my MRod tube, so is the MRod tube overkill strong or is the shotgun scary weak?
Let us know what you do, and post pix :)
Author:  kelly1 [ Wed Oct 23, 2019 11:23 pm ]
Post subject:  Re: Sealing a hole in an air tube.
EdLena wrote:
I drilled a hole (1/16") in an air tube to install a regulator. Now, if possible I'd like to change the hole location to accommodate a larger plenum.
I was thinking of attaching a shaped steel patch, say the size of a dime to the inside of the hole with silicone adhesive.
Has anyone sealed a hole like this?
Ed.



With some brands of guns a airtube isnt expensive , you might want to check.
The next time you are fitting a reg and tuning don't drill the hole until you have you're tune ,it wont be a problem for the short term.
Once you have everything close then drill the hole.,kelly
Author:  Gippeto [ Thu Oct 24, 2019 1:14 am ]
Post subject:  Re: Sealing a hole in an air tube.
Chevota wrote:
Assuming it's a typical 3Kpsi gun, and therefore rather thick; I'd tap the hole and thread in a screw. I'd find the smallest possible, like #2 or whatever fits best. Then I guess use JB Weld or Loctite 569 on it, but I'd imagine a variety of sealers/loctite would work. Once done and sanded down it'll be almost as if it never happened.
I would also smooth the inside edge of the hole so when push your valve or whatever past it it won't cut the O-ring. That may be tricky but it's doable.
But yea, the patch thing is a bad ideal unless the patch was fairly thick, but my first thought was; how are you going to get your valve in/out? I guess out the back? Some guns you can't do that, but maybe most you can? Of those you can I'm guessing it's not as easy as out the front? Maybe in your case it's no biggie? Either way it would bug the crap outta me to have a hole and a patch. The ground flush screw would bug me too, but not nearly as bad.
If it's a low pressure gun, like CO2, I'd likely still drill/tap but I may weld it. You can weld the thicker high pressure tube too, but considering the pressure, which already makes me uncomfortable, I'd be worried about stress cracking. I'm willing to bet the odds of that are ultra slim, but still...
Reminds me of a shotgun I have that has a thinner chamber wall than usual so I won't shoot full pressure loads outta it. I'm sure it's safe but I look at it and think 14000psi w/ my face inches behind it. Pass.... Come to think of it it's barely thicker than my MRod tube, so is the MRod tube overkill strong or is the shotgun scary weak?
Let us know what you do, and post pix :)


There are times in life when the question to ask is not "CAN we fix something", but rather "SHOULD we fix something. Attempting to seal the hole in this tube would be IMHO....an exercise in poor judgement.

We should also be thinking about the advice that we hand out...at some point, there will be someone who throws caution to the wind, takes piss poor advice from the "interwebs" and ends up paying the price.

Aside from that, all I have to say is....M-I-C....K-E-Y.... :roll:


Al
Author:  EdLena [ Thu Oct 24, 2019 5:08 am ]
Post subject:  Re: Sealing a hole in an air tube.
Chevota, tapping and sealing a screw into the hole will seal it but it won't strengthen the weakness that the hole created. Just like you can crack thick glass with just a scratch on the surface the tube just needs a single point of weakness to start splitting open.

Kelly1, Oshoot is sold out of replacement tubes but was selling them for $250. :rolleyes:
Good idea about tuning it without the hole first. I didn't know that could be done.

The more I think about it now any attempt to plug up the hole would be suicidal! Don't mess with HPA.

I'll place an add in the CAF Wanted for a tube---I may get lucky.

Ed.
Author:  kelly1 [ Thu Oct 24, 2019 11:20 am ]
Post subject:  Re: Sealing a hole in an air tube.
EdLena wrote:
Chevota, tapping and sealing a screw into the hole will seal it but it won't strengthen the weakness that the hole created. Just like you can crack thick glass with just a scratch on the surface the tube just needs a single point of weakness to start splitting open.

Kelly1, Oshoot is sold out of replacement tubes but was selling them for $250. :rolleyes:
Good idea about tuning it without the hole first. I didn't know that could be done.

The more I think about it now any attempt to plug up the hole would be suicidal! Don't mess with HPA.

I'll place an add in the CAF Wanted for a tube---I may get lucky.

Ed.

I have done 3 that way,playing with plenum lenght,kelly
Author:  kelly1 [ Thu Oct 24, 2019 11:28 am ]
Post subject:  Re: Sealing a hole in an air tube.
EdLena wrote:
I drilled a hole (1/16") in an air tube to install a regulator. Now, if possible I'd like to change the hole location to accommodate a larger plenum.
I was thinking of attaching a shaped steel patch, say the size of a dime to the inside of the hole with silicone adhesive.
Has anyone sealed a hole like this?
Ed.


The problem with the larger plenum is it would have to be signifigantly longer than original.
If you were making that big of a change ,then you could have a custom plenum spacer that has orings sealing it to the tube,but thats a huge change in tune,kelly
Author:  Chevota [ Fri Oct 25, 2019 2:21 pm ]
Post subject:  Re: Sealing a hole in an air tube.
EdLena: I know it won't strengthen it, but it will seal it and not leak or blow out, which was the point.
If anyone doesn't feel comfortable doing it then that's fine, but if for example my MRod had said hole I'd have no problem plugging it. At work I've taken much thinner tubing to much higher pressure so I don't see the problem at 3k. If the OP's gun is as thick as mine I don't know, so I suppose he'll have to be the judge. I guess you can always pressure test it after to see what happens. If it holds then great, if not then it was worth the loss + you get to see it vent or explode which I kinda want to see... Yes I was, and am, the guy that always had fireworks and was blowing stuff up ;)
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