I have a saying, Inventor fixes 100 problems and makes 99 more. I spend about 20 minutes a day cussing because that infernal program is such a clunkgasm of un-streamlined garbage. It's great at first, but then you realized that the people who made it never bothered to go back and actually USE it. Ul...

You should DEFINITELY buy ready made product.

Hey Cain, JSR is right, it would be a disservice to my partners to divulge design particulars. HOWEVER, I have a cadre of useful .ipt assets that would be useful, like the USG ignitor and regulator. I have never tried a different propane torch. Contact USG, they have a 10' length of hard to find 2.5...

Nope. No metering. Just a pressure regulator, an orifice, and a hole. The breech is open when feeding so spent fumes make their way out. Using combustion pressure to shut the air/fuel hole has crossed my mind. I work under a heavy load of self-imposed constraints. Cost, manufacture-ability and assem...

I'm with Technician on the valve issue. That's the way it was explained to me by the company reps that sell valves to my company. The new fueling system will hopefully cut charge times down. I don't want to give too much away, Jagerbond would shoot me. Here is what I think will work. I'll be testing...

I've been kicking around trying to figure out a way to get rid of the venturi, and I finally have a working bench top setup that not only has no separate venturi, but also no diffuser, metering or fan.

I've got a cart full of parts from McMaster Carr that I'm going to get to work.

Full pressure propane will not work with a blow torch venturi. The regulator is critical for consistent AF ratios, and keeping liquid fuel out of the lines. You are not the first person to suggest this.

@ Poland - I needed a way to actuate a valve using air pressure. Most valves are air piloted, not actuated. The Clippard components allowed me to do this. All this got dumped for the insanely simple current setup: http://lh5.ggpht.com/_9PhQzwI7-Fg/SiASCTN_WxI/AAAAAAAAB2Y/RNFjj4tF2oU/s800/diag3-Model...

I've got two. It never fails to amuse me when I pick it up. If you've ever had to stand and hold a flashlight for someone, this thing is awesome.

@Technician1002 That was actually my first prototype. It didn't work very well. http://propanetennisballcannon.blogspot.com/2009/04/flames-shoot-out_08.html There are a couple of reciprocating fueling designs out there, but you grossly overestimate my resources. I've kicked around something along th...

It ended up that the most cost effective solution to fueling was to just scavenge the venturi off a Bernzomatic blowtorch. It unfortunately limits the fuel and air flow. Adding more venturii or making a larger one would enable faster fueling, but cost more. I've got a design in the works that does t...

I've thought about doing this, but not only would it add what I feel is an unnecessary amount of additional complexity, it would substantially increase the price. The nature of the venturi is that it is impossible to over fuel once the regulator is dialed in. If anything, I would add an electric loc...

Ramses, yeah it's venturi. It's simple and always works.

I totally meant to scoot the table and instead wrecked the whole thing. Customers get provided with a detailed instruction sheet taped to the barrel. The marketing department suggested that some people can't, or can't be bothered to read so I made a short video. The beanie is to cover my bald spot a...

Haven't posted in a while. This is the instruction video for the what evolved from the 'ol contest cannon (which can barely be seen in the upper right corner).

[youtube][/youtube]