SpudFiles

ok I have been making a potato gun it has I believe a 1.25 inch barrel and a T section as a combustion chamber. with a 40 inch long barrel. my parents were cool with me making it on a trip to the store I got all my pvc but not enough money to get the glue. but I do have super glue now the question is should I use super glue instead of pvc glue

Absolutely not. Super glue will stick the two PVC pieces together. PVC glue will "weld" them together and make them one solid piece. Don't even consider using super glue; it will not work for pressure applications.

There was a discussion already about this so first search.

Second, it has been used and been able to withstand pressure, but really, i would never use it because pvc glue and cement are made to "weld" together the pipe and the fitting, as Velocity said, so just go with that, you'll be glad you did.

EDIT: Read please!

no. never. it will not hold the pressure as Velocity said. save up the 5 bucks it costs to get PVC primer and cement and use that, and be safe

ok so what do you think about my layout think is has any power ?

find the volume of your chamber and barrel using water- then see if you have an ideal chamber to barrel ratio, but that is an extremely depated topic.

i believe in teh .8:1, but i think somewhere there was a loong discussion about the true optimal ratio??

super glue has a very low shear strength, and that pressure is pushings the fitting apart, BAD!

ive actually found that superglue welds the pipe together like PVC glue does, except faster and it makes it much easier to not get the fitting all the way into the joint before it dries.

DONT USE SUPERGLUE.

Super glue has been proven to be able to hold a cannon together, but it is still kind of a stupid thing to do. They make specialized cement for good reason, and you really don't want to go looking for trouble with this sort of thing.

If you really don't have the $5 needed for a can of cement...mow someone's yard or something?

I have a little over ten years worth of experience and knowledge concerning gluing cannons together with super glue and I can say it works. However, its easy to poorly glue the joint (it has to be done a certain way) and f*ck up so you should stick to PVC cement whenever possible.

Using super glue and getting a good joint requires a certain process, experience, and lots of practice. Because of all this just use PVC cement, it's so much easier and a hell of a lot safer.