SpudFiles

I sorta thought you would have all seen his stuff but I guess it's not that old. I like the marble machines 8)

If I build one I'd large it up a bit

Style refined in aesthetics and a fantastic weapon. I like very much! :bounce:

I have been looking around for some possible safe to use indoor ammo, Nerf darts/balls, foam balls etc. Got some 20mm darts and 22mm foam balls coming, 3/4" Sch 40 PVC
Found a site selling balls for an airsoft grenade launcher, surprised to see how tight a fit they are

Material: High Density Foam
Dimensions: 50mm diameter for a superior air seal in a 40mm launcher.
Application: Used as a projectile for Airsoft M203 and other similar Airsoft Grenade Launchers.

Stealing my contest idea boy! Better not be touching oxygen....

Quite curious about your results with it though

No worries, I'm judging

20mm PCP custom build from Finland...

[youtube][/youtube]
I believe the barrel is from a 20mm cannon

Build Log on the GTA forums

uhhhh !!! awful! it sounds beautiful! :bounce: :bounce:

ITWOST, V1 didn't have the giddyup I needed, time to go over to a conventional(ish) hybrid cartridge. Hopefully my welding skills are sufficient. I expect 12ml at 28x should give me the required gas volume. If not, I'll be tapping gas from before the projectile for extraction.

oooh... watching this space.

Yeah, I tried PVC and an atmospheric pressure propane/O2 mix, but between turning the fittings narrower and you know, PVC, I had splitting problems and it wouldn't move my bolt simulator far enough. Stress testing on the fill valve/spark gap tomorrow (I hope). Built it in a threaded fitting so I can inspect it.

Zeus wrote:Yeah, I tried PVC and an atmospheric pressure propane/O2 mix, but between turning the fittings narrower and you know, PVC, I had splitting problems and it wouldn't move my bolt simulator far enough. Stress testing on the fill valve/spark gap tomorrow (I hope). Built it in a threaded fitting so I can inspect it.

What do you use to test O2?

I realized last night I need to stop whining about not having a lathe and just use what I've got...
So I shoved a nail in my drill and turned it with files.

I tried to make a nice dart for my blowgun, and I even attempted bluing the tip. Anyone have advice on getting a better color throughout the piece?

Try heating the metal to pale red, (obviously, before inserting the plastic), and immerse it in dirty engine oil. There remains, the metal, a blackish color. For the plastic, paint it, simply. Your darts are very nice.

I just used a series of 3/4" (20mm) PVC fittings, but to work in my device, I had to make them smaller. Unfortunately the fuel mix was a bit too powerful

I think this 3/8 solenoid valve will work nicely when triggered by the manual button [youtube][/youtube]