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Our first launcher was like this. We took one of those pink colored washers out of a garden hose and pushed it over the pipe and used the spring action of the cable ties to pull the bottle into the washer and seal it. It actually worked really well.Graveyard wrote:Nice looking couplings for the release mech. I've built some bottle couplings that has a 1/2" thru hole. They're not releases, just couplings. I place a garden hose washer between the bottle bottoms and torque them up.
Andicirk, we have not tested it to failure of the O-rings so we do not know the answer to your question. In theory it will hold as much as the PVC pipe can withstand before bursting or as much as the bottle neck can hold before it stretches out. Usually if used with a cable tie launcher it will stretch or break the ties well before the limit of the O-rings is reached.andicirk wrote:ive just noticed the cable tie launcher "o" ring solution , what sort of pressure does it hold before it leaks ( if it does at all) i know with using teflon thread tape i can get up to 9.5 bar ( limit of my present pump) and no leaks atm , but with wear and tear its a royal pain in the butt, renewing the tape , bending the cable ties back and retaping with your spare hand( foot) etc
on the same subject is there a tidy way to attach the cable ties so they dont look like a road kill?
I don't know how they measure it everywhere but in the USA they call out the diameter of pipe by the inside diameter. When I make a launcher, I use 1/2 inch PVC pipe. This fits exactly inside the opening of a bottle which is about 7/8 inches across. That makes the will thickness of the pipe about 3/16.andicirk wrote:ive been confused by a lot of the numbers given here , i undestaznd the imperial system and can roughly translate it into metrivc ie 3/8" is 9.6mm but i asume that if you say 3/8 pipe this refers to the internal dimmensions, not its external dimensions ........
It's a standard shelf item at Home Depot and Lowes home stores. The 3/8" pipe is in the same aisle as the PVC pipe. It's made of a slightly different compound known as "CPVC" which has additives that allow it to be used with hot water. Some locations may have local restrictions on the use of CPVC pipe so that may be why it is not in your local hardware store.JohnC wrote:US Water Rockets,
Where did you get 3/8" pipe? I can't find any pipe that fits snuggly into the 1/2" pipe of my launcher. Is the 3/8" pipe an 'off-the-shelf'-type item?
Thanks,
John
How do you make rocket go so high?U.S. Water Rockets1 wrote:It's a standard shelf item at Home Depot and Lowes home stores. The 3/8" pipe is in the same aisle as the PVC pipe. It's made of a slightly different compound known as "CPVC" which has additives that allow it to be used with hot water. Some locations may have local restrictions on the use of CPVC pipe so that may be why it is not in your local hardware store.JohnC wrote:US Water Rockets,
Where did you get 3/8" pipe? I can't find any pipe that fits snuggly into the 1/2" pipe of my launcher. Is the 3/8" pipe an 'off-the-shelf'-type item?
Thanks,
John
Thanks, I'll keep looking. Right now I'm using a 'bulge' in my launch pipe, but not all bottles are exactly the same and I get leakage sometimes. Once I find some 3/8" pipe I'll be in business!U.S. Water Rockets1 wrote:It's a standard shelf item at Home Depot and Lowes home stores. The 3/8" pipe is in the same aisle as the PVC pipe. It's made of a slightly different compound known as "CPVC" which has additives that allow it to be used with hot water. Some locations may have local restrictions on the use of CPVC pipe so that may be why it is not in your local hardware store.JohnC wrote:US Water Rockets,
Where did you get 3/8" pipe? I can't find any pipe that fits snuggly into the 1/2" pipe of my launcher. Is the 3/8" pipe an 'off-the-shelf'-type item?
Thanks,
John
When you get the o-ring working, you will not go back to any other setup. The o-ring launcher will easily hold more pressure without any leaks than the bottle can sustain without bursting. It will hold it for a long time as well. Years ago we had a reinforced bottle hold 250PSI overnight and it only lost 2 PSI and that may have been leaking at the valve and not the o-ring!JohnC wrote:Thanks, I'll keep looking. Right now I'm using a 'bulge' in my launch pipe, but not all bottles are exactly the same and I get leakage sometimes. Once I find some 3/8" pipe I'll be in business!U.S. Water Rockets1 wrote:It's a standard shelf item at Home Depot and Lowes home stores. The 3/8" pipe is in the same aisle as the PVC pipe. It's made of a slightly different compound known as "CPVC" which has additives that allow it to be used with hot water. Some locations may have local restrictions on the use of CPVC pipe so that may be why it is not in your local hardware store.JohnC wrote:US Water Rockets,
Where did you get 3/8" pipe? I can't find any pipe that fits snuggly into the 1/2" pipe of my launcher. Is the 3/8" pipe an 'off-the-shelf'-type item?
Thanks,
John
Howdy (Former) Neighbor!!!JohnC wrote:US Water Rockets,
Galway, NY sounded familiar to me and I finally looked up where it is. I lived in Ballston Spa for a short time while I was in the Navy. It was a nice place to live. Very snowy, but nice.