Everything I read about gas burners talks about the size of the mig tip.  My forge doesn't use a mig tip, but instead has a big brass part that serves the same purpose.  I don't know what the part is called.  Anyway I'm thinking the hole in mine is too big.  I stuck a piece of .030 mig wire in it and there was a lot of wiggle room.  Looking at it next to a .030 mig tip you can see a big difference in the size of the holes.  My forge will not get yellow hot.  I added a choke to it and that did help, but still not getting weld hot.  You guys think I need a smaller hole(mig tip)?  Are there replacement parts that will screw right on?  What is this part called?

0.030" mig wire is considerably smaller than a 0.030" mig contact tip. Mig contact tips are intended to allow the wire to pass easily and make electrical contact. The size printed on the contact tip is NOT the ID, it is the size wire it's intended for.

I don't understand what you have there for a propane jet nor what kind of burner it fits.

If you are getting your stock to yellow heat and it won't weld, you are doing something else wrong. 

I'll be more than happy to help but I need more info about what you have.

Frosty The Lucky.

The problem is that it is NOT getting yellow hot.  I haven't even tried welding because I know it isn't hot enough. 

This is a pre-made forge burner.  These parts have to be made for something.  I can't imagine that they manufacture these jets specifically for these little forges.  

Here's some pictures.  They were taken before I added refractory. 

 

From the picture your forge looks unlined, and if that is a hard firebrick it's not helping either.

3 minutes ago, The Jeff said:

From the picture your forge looks unlined, and if that is a hard firebrick it's not helping either.

I just said it was before I added refractory.   The brick is also gone now.

8 minutes ago, whitewill1412 said:

I just said it was before I added refractory.   The brick is also gone now.

Sorry missed that first time through.

You can see where the flame is burning and that is a B A D thing. 

Maybe Mike has some ideas to make that one work, I don't.

How do you feel about making a T burner, they're easy and not nearly as expensive as buying one of those or one like it.

Frosty The Lucky.

The choke solved the flame in the tube problem.  I probably will end up making a burner or 2, but I'd like to get this one working too.  It gets a bright orange color, but not yellow and the piece cools pretty quickly.   It burns through a lot of gas too.  That's another reason I'm thinking that hole is too big.

Good afternoon,

It's been a minute since I built or used a propane burner, but a few things that might help the cognescenti among us assess the issue:

1. Do you have any pictures of the forge after adding refractory and making changes.

2. Could you post video of the forge while it's running? This is often one of the most helpful things in making a diagnosis.

3. What kind of regulator do you have on it? What is it set to? How much is "a lot of fuel"? If it is pulling a lot of fuel, is there a possibility that it's freezing up?

4. Could you post a pic of the inside of the furnace? Preferably one where you can see how the burner sets.

5. This is more commentary - I'm just not a big fan of unshielded rubber hoses for propane. It's preferable for it to have some sort of protection from heat, impact or cuts, critters eating it, and the potential for hot stuff to fly onto it and melt a hole.

Here is a side by side of the jet and a .030 mig tip.  You can see there is a big difference in size.

I'm currently out of gas, so can't show it running.  I'll get more pics tomorrow. 

 

I found a picture of it lit.  In the picture it looks yellow, but in reality it is orange.

 

1 hour ago, Frosty said:

Maybe Mike has some ideas to make that one work, I don't.

You bet, Frosty.

The burner is a commercial reinterpretation of a Mikey burner; that makes it easy for me to know what is most wrong with it. What is it? The diameter of the gas orifice is way to large!!! This is why it is burning back into the mixing tube.

What to do? Your present brass gas orifice needs to be replaced or rebuilt. I suggest rebuilding it. How? drill out that gas orifice way larger

No; I didn't suddenly get even crazier. You need to drill out that center hole large enough to thread it for 3D printer nozzles. Then, buy a bag of nozzles (they're cheap), and the right tap. Why not use a MIG tip? I don't think you will find a MIG contact tip with a small enough through hole. I think you will find that this burner requires a 5mm (or 6mm) printer nozzle.

I don't like the cross tube, which they use to anchor the burner at a given depth in the forge. However, there is very little that can be done about that.

You need to get a bag of Plistix 900F to coat that forge's ceramic wool with. Rigidizer would be good too. Eventually, you will want to add a layer of Kast-O-lite 30 over the floor.

Good luck.

 

 

 

 

 

 

 

 

111

Knew I could count on you. 

Frosty The Lucky.

I already did the rigidizer and plistix.  It's in the last picture.

So you're saying that the hole in the mig tip is too big?  What size is the hole in the 3d nozzle?

Oh you meant .5 or .6mm

I believe you're right Will, Mike probably meant 0.5mm or 0.6mm. He'll be back with us.

Frosty The Lucky.

You got me; yes, I meant .5 or .6. Between 0.020" and O.027" (approximately). The smallest MIG contact tip that I know about is for 0.023" welding wire, and its through hole is supposed to be 0.031" diameter. Cheaper import tips are often up to 0.033" diameter

Why 3D printer nozzles? I am "gestimating" the size of that burner to be 1/2". I could be wrong. A typical mix of printer nozzles will have four or five different nozzle diameters (to cover my bet).

When you say the size of the burner how do you measure that?  I know the outer diameter of the burner is 1".  I measured it in order to make a choke for it.

Good grief Mike, I never run mig tips that small, normal for a 3/4" T burner is 0.035" and a 0.045" contact tip in a 1" T burner. 

Of course a T burner is a Jet ejector type burner, induces more combustion air for a give primary psi. (propane) and puts more flammable, air/propane at a lower velocity in the furnace chamber per second.

The practical size of a propane burner, the way we measure it here, is the ID of the mixing tube, not counting the flare and such. 

The OD of the mixing tube only counts when mounting it. 

Frosty The Lucky.

Ok I just measured the inner diameter and it is not perfectly round.  One way I get .86" and the other way is .89".  So it's actually quite a bit bigger than .5"

Ahhh, it's our day to miss a decimal place or two. I assume you mean 0.086" and 0.089".

But, YEAH those are too big! That is about 3.4x the dia. of a 0.023" contact tip which is about 8x the carrying capacity at a given pressure. No, that's just an estimation not a calculated number.

The point being, the carrying capacity of a tube is pi x square of it's radius. piRsq. I short cut it above by referring to the ratios, not specific numbers. 2x the dia. = 4x the area. 

Don't get hung up on precise calculations, these are home built burners, not wrist watches.

Frosty The Lucky.

No my numbers are right.  We must be talking about 2 different things.   I'm measuring the inside of the pipe that is the biggest part of the burner.   Isn't that the mixing tube you mentioned?

Ah, I thought we were talking about the mig tip hole. Please disregard my last post, my bad.

I don't think the slight difference in diameter is significant and may be an artefact of manufacture, maybe the weld seam or distortion from grinding the seam or maybe rough handling.

Frosty The Lucky.

Your numbers put it in the ballpark of a 3/4" burner, which would benifit from a .6mm printer nozzle.

Well me and my son both had the same idea to make the hole smaller.  It's the simplest possible solution and it worked.  We heated the tip with a torch and tapped it with a hammer to make the hole smaller.  I figured why not try it if I'm gonna cut the tip off anyway it wouldn't matter if I ruined the tip.  It was so easy.  Grabbed the piece with vise grips, heated just the tip with a regular little propane torch for maybe 30 seconds, and stood it up on the anvil and tapped the hole a few times with a small hammer and it got a lot smaller.  Now the forge gets so hot that I can hardly grab stuff out of it.  

I already ordered the printer tips.  I'll just hold on to them for future endeavors. 

You got the HEAT eh? ExcellenteMundo!

Will, Jargon is a trade language that allows people to talk about their craft without wasting time explaining what they mean. Make sense? 

It's time you start observing the jargon of home built propane burners and heck forges but that's more intuitive. 

There are different "tips" involved in burners it's meaningless when used without specifying which. If a person weren't following the thread they might be wondering why you're hammering on the mig contact "Tip." Yes? 

I'm glad you got it working properly, enjoy playing with fire and beating things with hammers.

Frosty The Lucky.