propane burners

[dian]

i have about a dozen different propane burners, some are bought, some self made. none of them will heat a small strip of sheet metal to more than medium orange (might be 900°c). even the mapp torch is no different. how come everybody on youtube is melting cast ron in crucibles and bringig steel up to welding temp.with propane?

flame temp. of propane is supposed to be 2'000c and i can adjust several burners to extremely lean (where the flame separates from the flare and goes out).

does anybody have a propane torch that will heat steel to a white color or even melt it?

edit: i became interested in this after my black-smith-friend bought a "profesional" double burner kiln and couldnt use it for damascus welding as intended.

[woodenbird]

I think you have to use oxygen with the propane to get the heat. On the farm we used propane and oxygen to cut steel. A bit cooler than actetylene but worked well.

[dian]

i have a oxy-propane cutting torch. i simply wonder how they do it with propane.

[Willy]

Build a firebrick stove around the item being heated to maximize the torch's capabilities.
Amazing amount of heat loss when out in the open. Oxyacetylene torches have a much hotter flame so the loss of BTUs are not noticed so much because with that heat source you can squander the heat and not be penalized as much.

[dian]

i have a (sort of kiln) and couldnt heat the steel to welding temp. so i started experimenting with the burners. i mean if the temp. is not high enough in the flame it wouldnt be in the kiln either, no? again, i was trying a small piece of thin steel.

[Doozer]

Temperature is likely not the problem.
Heat is your problem.

-D

[Ohio Mike]

how come everybody on youtube is melting cast ron in crucibles and bringig steel up to welding temp.with propane?

Air, lots of air. All the propane forges and foundry furnaces I know all use a blower to push air into the flame and the burner is tuned for that. White hot would be over 2000F.

That said there is huge leap from pouring aluminum or bronze and pouring iron. I thought the folks pouring iron were lighting on propane and burning diesel or propane/diesel mix.

[metalmagpie]

Just because you have a lot of burners doesn't mean that any of them are efficient at getting every bit of BTU out of your propane. I suggest you go read up on blacksmith forge burners. Here is a site you can get started:

https://hybridburners.com/products.html

Red heat is what, 1300F? And a propane/air flame is 2000F? There's plenty of temperature there, especially for sheet metal. I completely agree with the posting above about using firebricks to build temporary furnaces.

metalmagpie

[CarlByrns]

My son-in-law's company sells propane powered pottery kilns that get plenty hot but they have to be fed with a minimum of two 100lb tanks. On a cool day, three tanks are better.

[Black Forest]

It will be difficult to get steel or iron to the temperature needed to weld with just a propane burner. You will need to force air into the burner with a blower. I know many horse shoers that use propane for shaping shoes but can not weld in their forges. They use oxy/act for welding or a coal fired forge.

[deltap]

I have used a mapp turbo torch on a regular basis to braze copper pipe up to 1-1/2 inch. It's a red heat on copper so around 1100- 1200 F. This with the little yellow bottles from the hardware store. It would heat sheet metal to that temp also, but it would warp like crazy from the large heat affected zone.

[gellfex]

I've built a firebrick kiln for heat treating knives using propane torches, as others have said retaining the heat is the trick. If you don't want to use your oxy torch (why?) there's gas-air torches like this one I have that are popular with jewelry makers. Article comparing: https://www.achrnews.com/articles/12...y-fuel-torches

[outlawspeeder]

Oxygen or a venturi . I use the pressure from a propane tank to a mig .30 tip inside a pipe. The pressure pulls the air in and give me the heat to pour AU. For Iron, I thing you will have to up the game and use a blower. Look up a youtube guy SVSEEKER…

[metalmagpie]

It will be difficult to get steel or iron to the temperature needed to weld with just a propane burner. You will need to force air into the burner with a blower. I know many horse shoers that use propane for shaping shoes but can not weld in their forges. They use oxy/act for welding or a coal fired forge.

Respectfully, I disagree. There are many smiths around my area that weld steel using only a propane forge. As I said above, you have to have good burners.

metalmagpie

[Black Forest]

Respectfully, I disagree. There are many smiths around my area that weld steel using only a propane forge. As I said above, you have to have good burners.

metalmagpie

They must be using a blower on their forge. A normal farriers propane forge will not get the steel hot enough to create a good quality weld. Now if they have some super duper forge then maybe, but just maybe. I have not seen a farriers forge ever get the shoes white hot. Just cherry red.