I run mine on propane and compressed air. All I did was change the tip to a propane tip. It's much better with bottled oxygen but the compressor worked reasonably well. I made a forced air forge with propane and a hair dryer for years until I upgraded to a better blower system.

Make sure to use propane rated hoses as well, it will eventually eat your acetelene hose, particularly if you don't bleed them when not in use.

The the gas velocity out of the original nozzle is higher than propane's flame front speed until it slows in air away from the tip and you get to the actual flame front (hence the name). As you open up the air, you increase the nozzle velocity pushing the flame front further out. The flame front is where the gas velocity equals the propane flame front velocity. Generally nozzles are designed for the flame front to start just past the end of the nozzle. But you are using the nozzle end somewhat as a flame holder. You can also slow the nozzle velocity closer to the end of the nozzle by belling the end out. (VTsteam here, Ironman). Have you tried brazing with your torch?

In school in the UK during the 70's we had a similar setup using mains natural gas (mostly methane) and compressed air. From memory the torch was a bit different in that the burner had concentric gas and air jets, I think due to the low pressure of mains gas (20-25mb). but they were very effective for aneling soldering and brazing. I even managed to melt the brass boiler I was supposed to be silver soldering.😀

This is something I have wondered about for some time ( if you could use compressed air for gas cutting ) good to see I'm not the only one

Great demonstration. Like the torch but bet its a bit noisy live and up close. Thanks for the look!

as you turn on the air , hold the flame on the metal table to keep the flame close. ( for the hand torch) Propane is a slower burn and not as hot .

excellent vid thanks

Interesting, thanks.

Thanks for continuing to make videos. I'm finally melting aluminum and brass and copper. I can't wait to get to the point of cast iron. Not sure about propane physics but let us know in future videos what you learn

I have an Oxy/Propane torch set that I bought at a hardware store. I use it strictly as a cutting torch. 1/2" frame steel is no problem. It's very effective and the only down side, imo, is getting the Oxy bottle refilled ($$$). Nicely done video, Sir. thank you. Cheers from Alaska.

Nice video. I imagine the propane is being blown out as the air is only 20 odd percent oxygen. Another way to keep the flame inside the burner nozzle is to turn an internal taper from the outside lip the full length of the tube. Don't need much, around 3 degrees.

Did you try this on your wok? Looks like just the thing

Lovely useful tool

Nice work

Thanks for sharing 👍

Looks like your Mum didn't teach you how to get a candle to stand up, but I see you improvised pretty well later on. 🤣 I tried to do a similar thing with a cheap ebay oxy-acetylene type handpiece, but I had problems maintaining a flame with the supposed propane tip supplied. I tried making a dish in the end of the tip similar to the commercial oxy-lpg tips that are available, but that made very little improvement. I ended up making a side draft burner out of some pipe etc and that works well, but the flame is a bit big for fine soldering jobs - way too big really. I think that I will try to make a miniature version of what you have done to see if I can get a really small flame. Interesting video as always. Thanks.

If you perforated about 80% of that rear "shoulder" of your burner head, you wouldn't need the compressed air. Here in the states such "weed burner" torch heads are common. The velocity of the propane creates a natural draft, sucking in enough ambient air for an efficient burn if you regulate the propane flow and pressure

can cooking oil be used instead propane? BTW great videos 👍👍👍👍👍👍

Compressed air makes the flame blow out but what it really means is that the ratio of incombustible gas (nitrogen+ other gases around 80%)is too great ... The flair you made merely allows the incombustible gas to dilute enough to let the oxygen react with less hindrance.. Acetylene will ignite at mixtures from 2.5 percent to 82 percent, while the range for propane is 2.1 percent to 9.5 percent so you can use the standard tip if you reduce the oxygen flow greatly... however it will never be as hot as using oxygen...

silly question what relatively heavy metal aloys can you resonably safely melt and cast in your kitchen on a propane stove or something similar? i been wondering about that because i am building a train model that require some strategic placement of weights and cuting them out of lead is kind of not safe for kids process many older train models had hard lead weights in them and some even used them as a construction part so i started playing with that but i started to wonder how much of a health hazard is that. if i release that locomotive project as an open source design it might be banned for containing lead quite a lot of it actually, around 35 grams of heavy metals aloy that need to be filed , drilled and taped after which it is sealed in epoxy shell but people now are scared to even touch lead let alone breating in fumes from melting it is there a way to cast some safer aloy in high temp silicone molds ? like zamak or something without the use of a furnece what metals other than brass could be relatively heavy lead replacement, it does not need to be as heavy i jcan make pieces of a frame thicker so if you have any ideas about kitchen diecasting alternatives i would be really happy to hear them

Interesting subject. What was you straightened pipe made of, copper? I guess steel or stainless and not alum for the flair? Thanks

Do you have propane fuelled”tiger torches” or weed burners in Australia? They kind of resemble your torch but just use propane.

I'd have probably also investigated using swirl mixer vanes in the nozzle for even burning.

used a vacuum cleaner? Did I hear that right? How do you convert vacuum cleaner into a compressor airline

Should be possible to scale this down to a size/format where it will allow you to do some oxy/acetylene type work for propane money.... Maybe not welding but everything else one would use a oxy/acetylene torch for(which for most people is their main use for it rather than steel-filler steel welding...)...

Pop some molten wax from the candle on the table and then stick candle to that.

Some years ago I was building a small-ish jet engine from repurposed jet engine parts (It was still about 1 meter long and about 254mm in diameter, so in the grand scheme of things, relatively small) and had to re-engineer a suitable multi-fuel injection and ignition system to handle as high as a pressure as I could manage to flow, ~2000psi/130bar. While it'd be a little overkill for this application, stainless steel conical nipples can be had for fairly standard thread pitch (like NPT here in the US for example, or thread it yourself of course). I'm notoriously bad when it comes to drilling out tiny bit sizes and have a tendency to snap them even when lubed and used correctly, so for me, a commercial part worked better and had proven longevity. I also tried pressure washer ones that could work if you find the right spray pattern, however they aren't normally threaded like the ones I'm talking about; nothing a quick braze/solder job wouldn't fix, but for my project, swapping the nozzles out for maintenance and orifice size for different fuels was an objective. A little anti-seize and quick rub with nano-size graphite powder made it pretty easy even after extreme temperature cycling. It might be an option if one were to adapt it to plumbing parts to burn propane with adequate air pressure behind it and you didn't want to or have the tools to machine one from scratch. I'm sure I could dig up a link if anyone were to be interested.

Be careful not to force compressed air (higher pressure) up into your propane bottle (lower pressure). It could happen if the compressor regulator set to a high pressure.