With a potato, map landmark measured, the Taternator II will go just over 1000' with 2X MAPP, 8' long 1.5" barrel. Beyond that much power, I can't use potatoes because they liquefy. With other projectiles at 3X MAPP or oxy/acetylene, I can go well over 2000' but have not had a chance to do this at t...

What would happen if you just added pure oxygen? My guess would be its a bad idea . . . Good guess. There are two major issues with oxygen, but it is certainly possible to design around them: 1) Air is roughly 20% oxygen, so 100% oxygen needs 5 times the normal fuel charge to reach a stoichiometric...

I wonder what's gonna happen W/ that tripod When you fire that thing :roll: Should be fine. It is very rigid though it doesn't look it. The Taternator II tripod is a similar size and construction, the whole gun and tripod weighing a over 100 pounds, and with a 3x MAPP mix it hops the front feet off...

this is just crazy dude whats next? Besides future full-auto, I'm thinking of switching back to pure oxygen. I've beefed up the fuel injector/ignition since the earlier freaky (and damaging) tests with oxygen - no more nylon parts and a steel stiffening rod inside. TTD via DDT could be fun. I have ...

Remember not to take the fun out of the whole ritual in loading the gun . . . The gun stopped being fun to shoot about a month after I initially finished it :( so easy a Geico customer could do it. This video is the first time the guy ever saw the thing or touched a spud gun. What's fun NOW is extr...

. . . AND expensive. Why don't you call it THE BANKRUPTER? Not expensive at all. Fred had all of the material on hand already. The stainless is from milk pasturizing machinery. He's a frequent visitor to the metal scrapyard. A lot more sophisticated than gluing hunks of plastic together. I'll betch...

This is the ignitor used in my Taternator II . It can be made from cheap junkyard parts, any old mechanical ignition. When the button is pressed, current is sent to the coil through the normally-closed relay contacts. The relay is energized at the same moment, breaking the circuit to the ignition co...

Fred asked me to post this. It is not quite ready to fire yet. Should be capable of scary fuels like acetylene. All smooth bore stainless steel construction. Needs a name! The tripod is elegant but amazingly strong. Clever elevation mech. The rear chamber cap features a unique snap-shut vent for flu...

You're all probably sick of hearing about Taternator II improvements. I guess it's like people who have a baby and tell you every stupid thing it does like, "Baby had her first firm poop today!" They can't help it and they probably think it smells like roses. Anyhow, I've added a 3-way electric fuel...

I finally had a chance to wreck something for the camera. This was a sturdy box made from heavy 13/16 plywood. Operating in hybrid mode, conservative 2X mix Air/MAPP, the short 4' barrel, wax slug as discussed here , about 500FPS velocity. I posted a video with slow frame rate . Taternator II main s...

Hailfire753 wrote:Wow, sweet!! It is manually controlled, right? Not roboticly? It better not be, because that is what I am doing!

I just noticed your fine print - can't wait to see it! Build TWO while you're at it!

For this type of circuit the capacitor is the condensor from the old automotive points/rotor setup. Exactly - nothing to buy. The cap can be eliminated and the circuit should work fine. The life of the relay may be shortened a small amount, and the ciruit will make more radio frequency noise but he...

This is the ignitor used in my Taternator II . It can be made from cheap junkyard parts, any old mechanical ignition. When the button is pressed, current is sent to the coil through the normally-closed relay contacts. The relay is energized at the same moment, breaking the circuit to the ignition co...

Hailfire753 wrote:Wow, sweet!! It is manually controlled, right? Not roboticly? It better not be, because that is what I am doing!

Right. Just momentary toggles. Digital controllers are big money.

I must admit the controls are a bit 'jerky', or at least such is portrayed in the video. Possibility of knocking down the gearing ratio to reduce the issue? Anyway, your friend Fred looks like a good builder as well, I checked out his linked thread, nice work I must add. Taking a stab in the dark, ...