Need help with o ring size plesse

Discussion about Compressors, hose, pipes, fittings, launchers, release mechanisms, and launch tubes.
Hamby77
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Need help with o ring size plesse

Post by Hamby77 »

I built a launcher some years back with a one price pipe. I cut a groove into the pipe for the o ring to seat. I think I use 3/4 inch pvc. And now my o ring had final failed do to age. And I can't for the life of me remember what size o ring I used when I built it. :undecided: I do know that it only works with Pepsi bottles, not coke because the coke bottles are to tight. It has a Clark cable tie release on it. I real don't want to have to cut the launch tube in half to put a ring on. I just need to know what size I can slide down the tube to the groove to seal the bottle. I live in the middle of no where and will have to order one because the closet stores are 2hrs away. So any help would be greatly appreciated.
TH:
motorcyclepilot
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Re: Need help with o ring size plesse

Post by motorcyclepilot »

I recommend you sand your launch tube down a bit so it fits more bottles. The o-ring will take up the slack and provide a nice seal for all of them. I believe you have a 1/2" launch tube, if you are launching 2-liter soda bottles.

As to a replacement, I believe you will find it in one of these kits: http://www.harborfreight.com/catalogsea ... t?q=o-ring

It's okay if you have to stretch the o-ring over the launch tube, so long as it fits in the groove you have cut and is thick enough to seal against your rocket.

Good luck!
Hamby77
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Re: Need help with o ring size plesse

Post by Hamby77 »

TH: Thanks for the reply. And I do believe your right about it being 1/2 inch tubing DOH: I hadn't thought about sanding the tube but that's a great idea. Once again thank you.
Hamby77
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Joined: Sun Sep 20, 2015 2:45 pm

Re: Need help with o ring size plesse

Post by Hamby77 »

Would it be best to get SAE or metric sizes? And can any one please tell me right size I need. I know o rings come in different sizes. Out side and inside diameter and different #'s like #2 #3 ect. So I can simplify my buying. Sorry on a very strict budget here. Thank you very much in advance.