Automated fuel injection for Taternator II

[Dumbascii]

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 solenoid and simple controller which automatically fills the meter then fills the chamber. All you do is work the breech levers to load a spud then push the trigger. Lather, rinse, repeat. No valves to open, no switches to operate. Only works in conventional mode - hybrid mode is too complex to automate. Now the gun is REALLY begging for a linear actuator to open the breech. With a basket of spuds on top, it could then go full-auto! Maybe the world's first full-auto spud gun? That would make it difficult to switch to hybrid mode though.

Rate of fire is about 12 SPM or 5 seconds between shots. It could fire even faster, but I'd need a 3-way valve with bigger orifices to move the fuel a bit faster - takes a sec for the metered fuel to depressurize into the fuel injectors in the chamber which restrict the flow even more.

Here is the sequence of events and actions starting from the moment of firing:

Press trigger: Operates ignition relay and fires. Purge blower (fresh air) relay latches. Unlatches arming relay which silences the warning beeper and stops the flashing ARMED LED.

Start opening breech levers: Energizes 3-way fuel solenoid, regulated fuel begins flowing into meter. Purge blower is still running.

Breech reaches full open position: Unlatches purge blower relay, chamber is fresh now. Latches arming relay. Fuel solenoid is still energized, meter is just about full. Add new spud.

Breech reaches full closed position: Activates warning beeper and flashes the ARMED LED. Deenergizes 3-way fuel solenoid which allows metered fuel to flow into chamber injectors. Ready to fire.

Here's the controller schematic (click for huge). May contain errors! For the labeled pins on the Purge and Fuel switches, the labeled pin is active only while that condition is true, for example, the Purge Switch's "Breech Fully Open" pin is active only when the breech reaches the fully open stop position, and at all other breech positions the other pin is active.


Edit: Added images below


Sorry for the ugliness . . . Looks like a Borg.

[Hubb]

You're all probably sick of hearing about Taternator II...

I don't think any of us are tired of hearing about this. Just when one thinks it can't improve anymore...

Babies, on the other hand, are a different story.

[Dornep]

I'm new here and this is the first time I've seen this. You are God among men!

[dongfang]

Hi,

Well I would say, when the parents have the baby´s first poop gold plated and preserved to keep, then it´s getting too much...

Remember not to take the fun out of the whole ritual in loading the gun. I understand that you sometimes shoot with an audience.. maybe it is more fund for others to see you meter and inject fuel etc., rather than just pushing a button. But of course it is good fun to build the auto, too. At the first glance of your last picture, I thought, whaaat, did you pull the engine from a car there??

I have never heard about a full auto hybrid, either. But I am playing with the design for the STS-47 (Spud Transportation System), I have to admit.

As everybody else, I love your gun .. it´s serious stuff. Do you have a whole trailer for it ?

Regards
Soren

[Dumbascii]

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 extreme freaky fuels that really get your adrenaline pumping. Aside from that, there's little to do but build it more and more, way past the point of ridiculousness. Now I can either blow scheiße up with one serious ker-freakin-blam, or tear it to pieces with sustained rapid fire. Variety is the spice of life!

Do you have a whole trailer for it?

It comes apart in about 10 seconds. There are three components, the tripod with attached controller, the gun, a toolbox. Fits easily into a compact car with the back seat folded down. If installed, the 8' barrel/clamp assembly needs to be removed with two pins.

[thespeedycicada]

this is just crazy dude whats next? You gonna make it grow its own potatoes? or mabey you'll give it legs to wreak havoc on cities far away.oh yeah sic gun gets better and better every time.

[joannaardway]

Nope, I think I could hear another few dozen improvements before I even stop being fascinated by them. "Sick of" will take many times longer.

@Dongfang: There are semi-auto combustions but no full auto I am aware of. There are certainly no semi or full auto hybrids.

Of course, using electronics for an automatic is a bit of a cheat. A mechanical setup would have total "HOLY SH*T!!!!!" factor, but if it works, I suppose it doesn't matter really.

[Fnord]

Sorry for the ugliness . . . Looks like a Borg.

Uglyness? it looks cool as hell! (Wait.. that contradicts. Crap)
Yes, if it was painted black it would look very borg.

You don't have to worry about boring people with your improvements either.

@Dongfang: There are semi-auto combustions but no full auto I am aware of. There are certainly no semi or full auto hybrids.

There is one auto combustion lurking somewhere... I remember seeing a gun that bubbled a compressed air line up through a pool of alcohol to create an explosive mixture.

Other than that, I have a simple self-contained (no air tank), auto combustion idea that I don't have the motivation to build right now. I'm kinda waiting for the next contest, but I may end up building it before that happens.

[Dumbascii]

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 trouble getting past a 3x hybrid mix because of the unusual burst disk method I use. Oxygen instantly allows a 5x mix with little pressurization (just the 5 shots of fuel).

Of course, using electronics for an automatic is a bit of a cheat. A mechanical setup would have total "HOLY SH*T!!!!!" factor, but if it works, I suppose it doesn't matter really.

There is no way I could do full-auto without electricals. The breech is massive and needs to move slowly to give the purge and fuel operations time to complete. Before getting the 3-way solenoid, I had designed levers to operate the fuel valves mechanically from the breech. Electrical control is much simpler than mechanical would have been.

I have a simple self-contained (no air tank), auto combustion idea

If it's small and light enough, you could possibly power the breech off combustion gasses like an automatic rifle does. That motion would need to pump fresh air into the chamber and also operate the fuel valves. Make it seriously overpowered to compensate for the mechanical losses. Do you mind sharing your idea? I won't steal it . . .