Mini Hybrid

Harness the power of precision mixtures of pressurized flammable vapor. Safety first! These are advanced potato guns - not for the beginner.
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noname
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Fri Sep 15, 2006 10:21 pm

I'm going to make a really frickin small hybrid. Just a 3/4" or 1/2" SCH 80 nipple, a galvanized reducer to 1/8" Schrader, and a 1/2" or 3/4" union with a BB barrel on the other end. Probably just a BBQ igniter for the ignition.
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frankrede
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Fri Sep 15, 2006 10:50 pm

Good luck.
So your filling the propane and air from the shrader?
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noname
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Fri Sep 15, 2006 11:04 pm

Yep. Might be able to break 4x or maybe 5x. :twisted: Small Sch 80 pipe can hold A LOT of pressure, and steel is just not going to blow up no matter what you do to it.
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drac
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Sat Sep 16, 2006 11:34 am

Good luck getting the correct mix. Small chamber like that are a bitch to fuel.
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noname
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Sat Sep 16, 2006 1:27 pm

The propane meter is prbably going to be a nipple between a blowgun and a tire chuck.
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SpudStuff
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Sat Sep 16, 2006 1:34 pm

that is gonna be a lot of propane like 2x or 3x
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Pete Zaria
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Sat Sep 16, 2006 2:15 pm

How do you intend to pass the BBQ sparker wires into the chamber? The chamber conducts, so you can't use screws or something like that...

I'm working on a large-scale metal hybrid. For my ignition system, I pass the wires into the chamber through a quarter-inch bushing, with the space around the wires filled with JBweld. I use well-insulated wires connecting to a spark strip. You could build a mini spark strip and do something similar. Just put a T on the back with the schrader on one end and the ignition wires coming in the other.

By the way, with hybrids, smaller spark gaps work better. I'm talking teeny, 1/32" or so. A BBQ sparker might not be the best for this. Consider a camera flash (easy to build).

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Pete Zaria.
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noname
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Sat Sep 16, 2006 2:21 pm

There is going to be like 3/8" of exposed sch 80 in which I'll put two little screws like on <a href="http://home.comcast.net/~irwinner/potato.html"> this gun.</a>
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Pete Zaria
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Sat Sep 16, 2006 2:28 pm

Exposed sch 80 what? PVC or metal? You can't put screws for an ignition system through metal; the metal chamber will conduct (shorting the circuit) and you won't get a spark. If you're going to have exposed PVC that's taking pressure, then that will be the weak point of the gun...

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ProfessorAmadeus
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Sat Sep 16, 2006 2:38 pm

I think he meens PVC. This is gonna be cool.
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Pete Zaria
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Sat Sep 16, 2006 2:43 pm

My mistake, guys. I confused this with another thread and thought he was making the chamber out of metal. My apologies for the confusion.

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Pete Zaria.
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ProfessorAmadeus
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Sat Sep 16, 2006 2:50 pm

Well im not sure, you may be right. Well i guess we will have to wait for him to reply.
Insomniac wrote:Hey why am I a goose???? Why not somthing a little more awe inspireing, like an eagle or something? LOL
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Sat Sep 16, 2006 4:48 pm

What do you use to cement metal to pvc? That is why i changed my plans on the chambers i'm useing. A clue on this would be really cool.
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ProfessorAmadeus
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Sat Sep 16, 2006 5:09 pm

I think that you have to tread them together. Thats how people attach ball valves to simple pnuematics. I would also when treading it i would put epoxy on it.
Insomniac wrote:Hey why am I a goose???? Why not somthing a little more awe inspireing, like an eagle or something? LOL
SOO CUTE!! OMG!! I COULD JUST LICK YOU!!
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noname
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Sat Sep 16, 2006 5:44 pm

It's going to be a Sch 80 PVC nipple that's threaded on both ends. And thanks Professor, I might put JB Weld or something on the threads and screw them together fast or hook them up to a drill to spin them together before the epoxy dries.
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