I should try some solder, never thought of that as an attachment method. The only ones I've used are threads, hot glue, tar, and epoxy.

Incredible, very reminiscent of Iron Man. Awesome build, even the tacky sprinkler valve fits right in.

You can find plans for pneumatics just searching around on the internet. I have a good engineering brain and have figured out how to build a hybrid, combustion-piloted piston hybrid, REAL piston hybrid, and normal metered combustion. I have not the resources to build much beyond what I have which is...

Yah, loading is always the last thing, it's pointed downrange during and after loading. The reason I broke off two is because I wasn't sure what happened to the first, but I realized my mistake after that I designed a system involving an 1/2"-3/8" adapter, a 3/8"-1/4" bushing, creative cutting metho...

It is very possible. Just depends on what you're prepared or capable of spending on a project.

Wow, thanks for all the replies. I've got a rubber one to seal pretty darn well, so i'll look for other sources of micro-leaking since it seems they are pretty reliable. Doubt the schrader is the source, but if it is, I now know where to go for metal fittings on one! Thanks! The attachment system I ...

For quite a while I have been using a very ghetto attachment method to pressurize my pneumatic from a schrader valve- via air compressor or high-quality bike pump- and after working on this for a few months I designed a system involving an 1/2"-3/8" adapter, a 3/8"-1/4" bushing, creative cutting met...

Are you looking to make a real rocket, or something that's shot out of a spudgun?

"valve" seems to be the issue, not the ". I've never had a problem before either. Hope PCGuy has seen this.

I just got this error message when trying to search "3/4" exhaust valve":

Fatal error: Allowed memory size of 16777216 bytes exhausted (tried to allocate 71 bytes) in /home/spudfile/public_html/forums/search.php on line 813

If you're looking to do electrolysis experiments on your own, cut up a pencil and take out the graphite inside, it makes very good stable electrodes for all sorts of experiments. Just be careful, since I know from personal experience that salt water will produce Cl2 and NaOH.

I'd say for such a heavy projectile, you'd need a hybrid to get any significant range, or a massive air chamber (like those the mythbusters used in their attempts to tenderize steak and rip apart a baseball), but such a size would be very unwieldy.

If you can, hybrid I say.

Thanks! hysten and I have been working together, as amateurs, only real success has been with the piston valve, but we are looking for new ideas, and to expand our knowledge.

Wow, this website is truly a fount of knowledge. Not to be hijacking or anything, but does anyone know how much more efficient a hammer valve is than a piston valve?