SpudFiles

for my pneumatic cannon i tapped the hole for the gauge with the gauge. the hole looked pretty nicely tapped with the fitting but when i put it in it leaked. i already tried tons of tefflon tape but it still leaks. im weary about using epoxy or something because if it still leaks im screwed. any suggestions?

another idea is just to fill the hole somehow and tap another hole with a tap (i just found a tap that is the same threading as the gauge). how would i go about filling the hole (about 1/4 inch) or patching it so it will hold pressure?

You can't fill the hole that would be a major weak spot - you should have found the right tap in the first place i am afraid

is there no way you could try tapping the same hole and seeing if you cut some better threads - otherwise i can't think of much else you can do apart from a new pipe

i would also try some epoxy resin but like you said it needs to be done right otherwise your screwed sorry i cant help more fella!!!!!

Put tons of epoxy on the male threads of the guage and on the inside of the hole, then screw it in. It should work. If you don't want to do that, cut the pipe in half next to the hole and glue both ends into a coupler and drill a new hole.

You should be just fine if you put some epoxy (I recommend JB Weld) on the threads and screw it in. Just make sure not to plug the hole for the air to get in your gauge.