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I've been doing some experimenting with a liquid fuel burner of my own design, with frequent changes, and decided to document it on a thread. Any suggestions are welcome.

the first two videos are of it running with methanol, which didn't work outside the forge, the flame would go out just as it would start vaporizing. The second video is it running with white gas, which improved the fuel air mixture (3.5 times more fuel/air)

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Liquid fueled forges are an attractive thought but I don't know of one that works worth spit smaller than a 55gl drum and it uses a fuel oil furnace burner. 

Besides being  hard to get to work will at all they're more dangerous than most folk think. Leaking fuel oil is pretty explosive and say recycled cooking oil is problematical.

Still, you might come up with something workable, just be very VERY careful.

Frosty The Lucky.

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@Andrew Golabek, it would be nice if we could see those videos without having to download them. Could you put them on your own youtube channel (or the like) and then post links so we can watch them online? Thanks.

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Liquid fueled forges are an attractive thought but I don't know of one that works worth spit smaller than a 55gl drum and it uses a fuel oil furnace burner. 

Besides being  hard to get to work will at all they're more dangerous than most folk think. Leaking fuel oil is pretty explosive and say recycled cooking oil is problematical.

Still, you might come up with something workable, just be very VERY careful.

Frosty The Lucky.

Yes, being very careful, and I'm exploring with fuels other than oil, and one a small scale

 

@Andrew Golabek, it would be nice if we could see those videos without having to download them. Could you put them on your own youtube channel (or the like) and then post links so we can watch them online? Thanks.

Yes of course! I'll upload them tonight

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The trouble with fuels other than oils is energy density, methanol or gasoline don't carry as many BTUs per unit as oil so consumption per BTU goes up and temp goes down. Temp doesn't always go down but it usually does. When you start trying to burn fuels denser than fuel oils you start running into metering and flow problems. To even get waste oil burners to work at all usually takes a pre-burn chamber and the heater burner is burning unburnt fuel. A few years ago there was a guy posted here for a while that was showing off some of "his" inventive genius by melting aluminum in a waste oil fired melter. Scary lash up all round and it looked like he was testing it about 10' from the house. 

Not saying the pre burn super heater burner won't work I just never have liked how they felt to me safety wise. They've been around since the '60s  in Popular Science and Popular Mechanics, later  "Mother Earth News" in what the '70s?

Yes, Youtube. Please.

Frosty The Lucky.

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The initial yellow flames are from the fuel I used to preheat the coil at the front of the burner. This new update increased the fuel flow which successfully prevented burning back in the tube. A check valve was also added closer to the burner to stop the back pressure , which would cause it to burn inconsistently. In the video I adjust the fuel pressure slightly testing it out. Next changes are going to be a longer fuel line, moving the fuel inlet further back, and increasing the diameter of the heating coil. 

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Nothing new, just decided to compile all the stuff I did up until now, at the time of many of the things here I was going based off other youtube videos, so... haha, still someone might find some useful ideas from this. Two weeks until I get to make changes to the burner, and test it out, and make a new forge.

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Got a needle valve installed, and tested it in the dark tonight, tried both methanol, and camping "white gas". Suffice to say that methanol does not work easily in a naturally aspirated burner. The gas however seems to work very well, video up soon.

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here it is running in the daytime on camping gasoline, it has many flame problems, with the huffing at lower pressures, and the flame coming off the end of the nozzle at high pressure. In person the colour of the flame transitions as well as the pressure increases, from a light blue to a darker almost purple. As I think it becomes more oxidizing. If I can I will add a larger nozzle, or add more flare to the existing one. Also something I tried to protect the nozzle (black pipe nipple), was a coating of calcined alumina with bentonite, which seems to work well, as you can see the flame is clean from oxidized iron colouring. Any suggestions to improve the burner?

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Since stores aren't open right now because of thanksgiving, I couldn't get any supplies to improve the burner in any meaningful way. I just made the coil slightly larger diameter, and decided to put it in my old mini coffee can forge, to see if it would help with the problem of the flame coming off the end of the burner. It was successful, and it melted a small piece of copper in the forge with no insulation or lid. Here's a video of it running soon after I started it up.

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The design of this burner is quite simple, the fuel runs under pressure through a needle valve to control the rate, then through a check valve to prevent back pressure affecting the rate, and vapour lock problems. The fuel then runs through a set of coils infront of the burner nozzle, and to the back of the burner where it exits in the same fashion as a propane burner. As of now it doesn't have a set orifice size for the gas coming into the burner, but just comes out of the tube. The gas comes out at a high velocity because it has been boiled inside the tube like a Coleman stove, and it induces its own air into the burner. 

Current issues with the deaign include:

-flame easily overpowered by the fuel/air mixture velocity, the flame will lift off the end of the burner and then go out if you don't quickly reduce the fuel rate.(although I have managed to keep a lifted flame steady for up to 5 seconds before blow out.

-if there are too many coils then the fuel is vaporized to too high a temperature which causes it to become less dense, this increases the amount of air induced into the burner and makes the flame too oxidizing.

-if there aren't enough coils the fuel doesn't vaporize fast enough for the fuel rate. Enough said about that.

-there isn't a choke on the burner.

-it is very sensitive to small changes in the fuel rate when outside of the forge.

I refer to fuel rate rather than fuel pressure because the fuel is delivered from a high pressure source through a valve which controls the rate but not the pressure, this is important to prevent vapour lock and an unstable flame. 

-the copper tube used to deliver the fuel is easily knocked out of alignment with the burner mixing tube.

 

 

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Today I got a new fuel line, and made a new nozzle which has a much larger diameter, and almost no taper (3.9cm internal diameter). The air intake was further opened, chamfered and polished, along with the exit of the mixing tube into the nozzle. The flame is what appears to me in person as perfectly neutral, and very stable. The fuel valve can be opened with no risk of the flame blowing out.

I was wondering if it would be acceptable to post some of the flame pictures in a thread on the gas forges forum, along with descriptions of what I did to improve the burner.

For those wondering the basis of the parts used to make the burner as is are, 6inch 3/4 black pipe nipple as mixing tube, 3/4-1inch bell reducer with the threads fully removed chamfered and polished, along with the entrances and exits of the mixing tube. The fuel line is a 1/8th inch auto meter 3224 copper tube, which directly jets the has in vaporized form. The nozzle is a exhaust coupling which was cut short and spaced on with two layers of the cut offs. The nozzle was attached with 2800f metal-metal mortar/cement. There is a check valve which is a 3000psi air valve I had spare.

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This design allows only a small volume of fuel to be heated at once, just the volume of the 1-8th inch copper tube which is used to vaporize the fuel. It also doesn't require any air source (the fuel doesn't need to be atomized, it's vaporized instead). The fuel simply needs to be pressurized like in a Coleman stove, or with a fuel pump, this can be kept away from the burner/forge. Currently the fuel is pressurized to 40 to 60psi and the rate is controlled with a needle valve. I think it might work down to 15psi, but I haven't tried since it was redesigned. In the past running the fuel at lower pressure made it huff and go out easily because it would cause vapour lock. The check valve prevents this becoming a problem, but I haven't tested at lower pressures yet. 

The new nozzle and other small changes fixed almost every problem it had, the flame is now very stable. 

The next changes to include will be a small fuel filter, and trying the new design in a forge once my forge is built. Also polishing the nozzle in hopes it will become coloured from oxidation. Eventually a choke will be added for more control.

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Got everything needed to out the forge together finally.

10.5 diameter by 13 inch tall steel can

Burner, mounts

Ceramic blanket, and rigidizer (going to have 2 inches)

1 inch hard Firebrick as floor removable protection. 

Zircon, and bentonite for coating ceramic blanket for ir reflection 

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