My first spud gun

[farcticox1]

I'm not a combustion guy but pictures would be good

[Potato Demon]

Sure thing I’ll post a pic of 2 of my 3 spud guns.

It might be a while because I’m currently away from a proper computer and the editor doesn’t work very well on an iPhone.

[Potato Demon]

Ok here’s a picture of my first 2 potato cannons. The big one was my first one the small one was my second. They’re both solid core abs. I get my abs from home hardware, Home Depot where I live only has cellular core abs for some reason.

[Potato Demon]

The tape on the chambers is for grip.

[jackssmirkingrevenge]

Primitive but still fun what's your ignition like and are you metering your fuel in some way?

[Potato Demon]

My ignition is two small nails and the piezoelectric thing from a bbq lighter. They work pretty well and I use hairspray or deodorant in them. If anyone knows of a better fuel let me know.

[Potato Demon]

I could send a picture of my third combustion and when I finish it my first pneumatic.

[Potato Demon]

First pneumatic is built I will post pictures tomorrow if anyone want me to.

[jackssmirkingrevenge]

If anyone knows of a better fuel let me know.

syringe metering ftw!

[youtube][/youtube]

[Potato Demon]

I haven’t tried syringe metering yet, I just count to 10 quickly and then stop spraying. I just made a spud gun with a 4”x1’ combustion chamber and a 1 1/2” x 3’ barrel btw.

[farcticox1]

First pneumatic is built I will post pictures tomorrow if anyone want me to.

Yes, I likes pneumatics

[Potato Demon]

Ok here is a picture. I’m waiting for the cement to set (transition cement). The only reason I built it with ABS is because I had some scrap. I know that abs isn’t the best for pneumatics but if it fails it ruptures and I could probably salvage the valve with a saw and a core drill bit (or whatever it’s called). This is solid core abs by the way. I used the valve from some scrap inner tube and drilled a hole in the chamber that was smaller than the valve, then I put the valve into my drill and held it to the hole and turned on my drill. Because of the rubber on the valve it fit perfectly. I added a ton of hot glue just to be safe.

[farcticox1]

So the ball valve is the trigger? They work really well when spring loaded, then you can have a better trigger

[Potato Demon]

I was actually trying to figure out how to spring load it. What I have done to make it easier to turn (haven’t got around to firing it yet) is I put a thin layer of Vaseline in the ball valve and that seems to help a little.

[farcticox1]

You'll need to make some kind of linkage. Attach a spring to the valve handle somehow, maybe need to extend the handle? then someway of locking and releasing the handle or spring.

musket_trigger.jpg (20.26 KiB) Viewed 6748 times

This is one I made but it did get complicated