Good morning all, I have a forge I built with burners based on this design:

https://althoffwoodshop.com/blogs/main/forge-build-part-i-building-the-burners?srsltid=AfmBOoqjCx3s6BJB8fp32IsS9slCT3xlkMUHaDDsWM0sLvghsnNGQRGW

 

Originally I had a reducer on the end as the flare.  It was a 3/4" to 1" bell reducer that I ground the grooves off on the larger end.  This worked very well, but the flame was igniting inside the reducer causing the bell to get red red red hot.  After doing some looking and reading, I replaced the reducer with a stainless steel coupler as the nozzle end.  I have not ground the grooves down on the flame end of this reducer after seeing Frosty mention in another thread how that was not necessary.  Now, I cannot get the dang thing to light without the flame detaching from the front of the burner very far into the forge.  I am running propane at 20psi that feeds into a needle valve I can set from 0-20psi.  At 1-2 psi I cannot get the flame to catch.  At 5 psi, it will light but I cannot get it to stabilize without shooting off the end of the burner.  I have messed with the collar covering the port holes but cannot make fine enough adjustments I think.  I am using .035 mig tips for the accelerator and have also tried .020 tips with no improvement.  I will try and get some pictures of the burners this evening, but wanted to see if anyone had tips before then.

There are several potential reasons for what you are experiencing.  You'll have to do some troubleshooting to narrow down the cause.  However, I'll give you the 3 most likely reasons (in my opinion) that this could be happening.

1.  Too much air being drawn in compared to the fuel.  It's hard to keep a really lean flame lit without it blowing off the end of the burner.

2. Axial alignment of the mig tip inside the mixing tube.  If the fuel stream is not centered in the mixing tube the burner will not function correctly.

3. Debris in the jet orifice restricting the fuel flow.

You did not mention where you had the choke set or if you changed it when experiencing this problem.  Try choking off most of the air to see if you can get a stable flame.  If you do and the flame is blue-greenish then open the choke a bit more until it turns a medium blue color.

Moving to a .020 tip would only make the situation worse.  If you constructed the burner correctly and you have centered the mig tip properly then the prescribed mig tip size should work.  If anything you'd want to move up in mig tip diameter, but again if you made it correctly that should not be necessary.

I guess I should have started with this: Hopefully you constructed the burner exactly as described by Mr. Porter in his book.  Deviation in dimensions or parts almost always results in negative effects on burner performance.  Mike checks in here on a regular basis, and in theory you made a burner based on his design, so he should be able to help you sort this out.

I strongly suggest you pick a better set of plans and follow them, NOT base your build off them. The site attached to the link is a marketing site, not a place to find good information. 

FYI, the author of the book being sold on the site, Mike Porter is a member of IFI and occasionally posts.

If you open the Gas burner sub section of Iforgeiron, you'll find many threads about building NA (Naturally Aspirated) propane burners. Mike is a large contributor as am I. 

I build a very different type of burner but the flame breaking away from the end of the burner nozzle is a symptom of a couple potential problems. If you post some pics of your burner in operation IN the forge we'll be able to evaluate the various conditions and be able to offer some useful suggestions. 

Unfortunately you are too new to this aspect of the craft to even know what to ask or what to describe, etc. I'm not dissing you, it's just a simple statement. We'll be more than happy to help you with your burner and you'll learn about how the things work. 

A win win. No?

Frosty The Lucky.

I appreciate the replies. I would gladly upload a video of it working in the forge, but it won't work long enough for that. I took them out of the forge to try and light it outside the forge and had the same issue. I have tried tuning the choke in every conceivable possible way. With it *barely* cracked a flame will light but that is with almost zero pressure on the needle valve. It won't stay lit without the flame being green. The tiniest change in opening the choke, causes the flame to shoot off the end and die. 

With that in mind, I am taking Frosties recommendation and finding a new burner to build. Now I just gotta find the gas burner subsection. I see "ribbon burner" but not gas burner. I'll find it eventually.

Ok a quick update. For poops and giggles, since I plan on replacing the burners unless I can figure this out, I ground down the threads in the coupler I am using as a flare end. Doing that let's the burner ignite and burn. Only problem is, it's just like before and appears to be igniting inside the flare. Since I know a flare is to help slow down the air/fuel mixture to burn, is it possible it's slowing down *too* much, or am I just overthinking this?

Either you don't understand what I said.

Or have have decided to disregard my efforts and are going to try to making an unsalvageable burner work and I can do something else. 

You can't do both. Chose.

One last "thought" for before you decide. How are you going to make it work if you can't even find the CLEARLY LABLED Gas burner section of the forum?

Just so you know, I've wasted I don't know how many hours trying to help someone who asked for help only to have them argue about having found something on the web they want to try. And of course ask ME how to make it work. 

I do NOT do that anymore.

Frosty, I am not saying I'm not going to listen to you. I like to figure things out and understand what's wrong to improve it. I did this as a test for my own curiosity. I've already gotten the book by Mike on burners to read through it and plan on following his directions in said book. I'm sorry for being curious and trying to understand why the burner I made isn't working for my own edification. And I don't know why I can't find it. The only thing I can imagine is I'm doing this on my phone and that is somehow screwing with the format so I can't see it. No need to be rude about it.

Fair enough. Let me know when or if you wish to continue.

 

Ok, I cannot find a subsection called "gas burners" anywhere on Iforgeiron. I see a sticky labeled "Burners 101" and a subsection called "Ribbon Burners" within the "Gas Forges" section, but nothing called "gas burners".

Beyond that, I'm going to follow Mike's instructions to make some new burners and will update when that is complete.

The Burners 101 is the thread that deals with gas burners. Have you read the "Read This First" thread? It will help with getting the best out of the forum, like how to do the best search as the search function of the forum leaves a lot to be desired, putting it mildly. Also knowing where you are located may have members who are close enough to visit and help you out.

I can’t control the wind. All I can do is adjust my sails. ~Semper Paratus~

I just saw that about the searches on the read this first part. I also updated my profile. I got a message suggesting the same thing as you haha.

If you've gotten Mike's book you are on the right track.  As said before though, do not attempt to use components other than those specified.  Despite these burners being DIY, there is a fair amount of precision needed for them to function correctly.  Something that is "close" may end up making the burner significantly less efficient or possibly non-functional.

As for the flame burning in the flare-- they are supposed to do that.  There should be no flames inside the mixing tube, but there will be at the end of the mixing tube inside the flare.  The flare is a consumable item that will have to be replaced from time to time.  It will become oxidized over time and deteriorate - even stainless steel.

Buzz, thank you. Whenever I read that flame in the nozzle was bad, I alway pictured the flare as the nozzle and not the burner tube. That makes a lot more sense. 

I have Mike's book and have most of what I need to make that burner. I'm taking his advice from another thread and using schedule 80 brass tubing instead of schedule 40 so I don't have to brake anything.

One of the challenges starting out in any new field is learning the lingo.  We have to make sure we're talking about the same things in order to troubleshoot and give advice.  That's why you'll see some people seem nit-picky over terms.  It can be confusing enough even when we're all on the same page, but when we're not it's darn near impossible to have a productive discussion.

Obviously if the designer recommends a part change from his original plans you go with that.  Likewise if he writes anything here that contradicts something I've written you should always assume he's right and I'm wrong.  There could be a slight chance it goes the other way, but the smart money will bet on Mikey.

Totally agree Buzz.  Lingo is important

The one question I have for Mike is his recommendation to use schedule 80 brass instead of 40 for the flame:

"(1) Change out the recommended schedule #40 1/8" pipe nipple for a schedule # 80 nipple, which you can tap the 1/4-28 thread directly into, and thus exchange a bunch of extra steps and silver brazing for increased performance."

I just want to make sure I am doing it right and this means I can skip using the brass nuts that hold the mig tip and screw the tip directly onto the brass nipple?  Am I still supposed to cut off the threaded end the tip goes into like it shows in his book when you are using the two brass nuts?

 

 

21 hours ago, Kintan said:

The one question I have for Mike is his recommendation to use schedule 80 brass instead of 40 for the flame:

"(1) Change out the recommended schedule #40 1/8" pipe nipple for a schedule # 80 nipple, which you can tap the 1/4-28 thread directly into, and thus exchange a bunch of extra steps and silver brazing for increased performance."

The point of using schedule #80 1/8" pipe for the gas tube, is not about ease of build; that is a very nice side benefit. The point of using  schedule #80 1/8" pipe is that its inside diameter is approximately 3/16". After you run threads for your MIG tip into that pipe, rather than a schedule #40 1/8" pipe, you end up with a smoother transition of gas between the pipe and MIG tip. In the book I called the gas pipe and MIG tip an accelerator, for very good reason. HINT, HINT!

The point of brass pipe, rather then steel pipe, is not that it is easier to thread; once again, that is merely a nice side benefit. The point is that brass schedule #80 1/8" pipe is easier for people to find online, because it costs more money; charging more is near and dear to sellers black little hearts. If you can find the right steel pipe, fine and dandy. 

Since you have the book, it should be easy enough for you to rebuild your burners to conform to my design, starting with reshaping those rounded ends of the burners air slots, that the other guy used. I made the point repeatedly that that was a none starter!!!

If you want to spend the time, after you understand the burner's design principles, to change and test these burners, good for you. Several people on IFI have done so, quite successfully. Two different commercial burners used my design with some changes, for commercial reasons; both were highly successful; I applaud that.

It is possible to use a reducer as the burner's flame retention nozzle. It is also possible to use no nozzle at all; both method works...kind of. However, the nozzle I designed for this burner is one of the factors used to tune it for its promised superior flame.

Finally, in the book I told the reader how to use three set screws to position the accelerator dead center; do so, and good luck.

The author.

Glad to see you jump in Mike. Do you still prefer 3 air intake slots?

Frosty The Lucky.

Yes, Frosty.

I prefer three air intakes. In the book I used more intakes on the larger burners, but never two, or four, or six intakes, the point of odd, rather than even numbers is to insure that incoming are will spin the maximum amount, because no intakes end up opposite each other. You want the spin from each air intake adding to the others; not slowing the other's spin.

  Post book I came to see that three air intakes is optimal, because this number gives maximum spin and maximum use of space; the more ribs that are needed between increased numbers of air intakes the less room left for either intakes or ribs; a lose, lose situation 

  Is there ever a time when even numbers of intakes makes good sense? Yup, indeedy so. 1/4" Mikey burners are both far more difficult for people to build, and way to strong!  The main thing they need is some de-tuning. Two air entrances actually work out better than three; only in this burner size.

  I built a 1/4" Mikey burner with three air entrances, and it created perfect flames...with very little turn-down range. Two different guys on IFI built the same burner with two air intakes, with perfectly acceptable flames, and good turn-down ranges (with a lot less work) 

  We must understand the reason why in a design; then we can make intelligent changes to that design. Otherwise, we crash and burn.

Note: It has also been shown that diagonal air intakes are superior to rectangles. However, only enthusiasts will make that kind of effort.
 

Thanks for the tips Mike! I will make sure to use them as intended. For the schedule 80 nipple, should I cut the threads off one end or file them down, or will that not affect anything?

Kintan,

Assuming that you are employing a schedule #80 1/8" pipe nipple, you would probably end up cutting it in half, internally threading the cut ends, and screwing hose fittings or needle valves unto the remaining threaded ends.

But, but, but, what if the two halves of that nipple end up to short?!? The change to schedule #80 pipe improves internal flow so much that you can use a pipe only two-thirds the length recommended in the book, and it will still work just fine.

I do recommend beveling the cut ends of the nipple after they are threaded for the MIG tips. Yup; this is done to keep maximum flow of incoming air past that point. However, anyone could tell you that I am a notorious picky-but. Loads of people ignore this advice without any harm.

Nevertheless I is right and they is wrong...so wrong. You believes me don't you? 

I figured, 3 slots work better largely because the intake flows don't run into another one head on half way across the tube and become turbulent. 

BOY for a notorious picky butt I don't see any mention of being careful to KNOW what size and pitch threads the mig contact tips have. There are so many suppliers from around the world of both welders and parts you can't just walk in and out with 1/4" x 28 mig tips.

If you go to a real welding supply rather than the local hardware of big box, the welding supply will carry taps for whatever mig tips you buy. Welders use them to chase the threads in tips that get burnt or the wire sticks and buggers it. 

Frosty The Lucky.

Thanks Mike! And I do believe you! Frosty you are spot on about the mig tip threads. I do have the right taps and bits for them

1 hour ago, Frosty said:

I don't see any mention of being careful to KNOW what size and pitch threads the mig contact tips have. There are so many suppliers from around the world of both welders and parts you can't just walk in and out with 1/4" x 28 mig tips.

Exactly, Frosty,

Not to mention MIG contact tips that have no thread at all. When giving instructions for a particular burner, of a particular size, I give that kind of advice. Here...not so much; he is already committed to 1/4-27 (or 1/4-28 if he must) thread by the gas pipe. Twenty-five years ago my favorite MIG tips were a completely different length and diameter from the ones I recommended then and now; but they were expensive and hard to find. Readers just don't need the grief.

I bought Twecos by the box, I still have 30 or so out in the shop, plus bits and taps for the selection of later versions. I recommend to guys just getting into building burners they buy a packet of tips AND the bit and tap to go with to keep together in the tool or whatever box. I have a stack of cigar boxes with jets, fittings and tools for particular burner builds. 

Frosty The Lucky.

 

Most of the research and design time I put in has to do with repurposing burner parts, like MIG tips and 3D printer nozzles, in an ever changing market. The latest twist is mention on here of a ".020" MIG contact tip. If true, I will have some changes to make in my burner plans.