bluesman7

I'm not very experienced looking a propane/air flames, but that looks rich to me, I've found that having a CO monitor in the shop is.... ahem, useful. I had my burner tuned neutral in free air, then when running in the forge. at the same settings, being reducing and producing CO, even though it looked pretty good through a peep hole into the forge.

For videos check out Brian Brazeal's tong making videos. Tongs are not considered a beginner level project, but I certainly learned a lot by making several sets of tongs. So far all of my tongs are self made.

Moving the choke to the other side did improve the flame significantly. I'll play around with the nozzle overhang a bit before putting the burner back into the forge. Thank you!

I can easily shorten it, but there may be a design issue with the nozzle. The nozzle is a straight 1-3/8" bore. The outside end of the 3/4" burner tube is built up to this same 1-3/8" size. This is what fits my forge. Do I understand correctly that your normal stepped nozzle for a 3/4" burner is made from 1" pipe"? I can make another burner to use a different size nozzle, but I would like to get the present burner running as good as possible to use in my existing forge. I lengthened the overhang after the choke mod because I thought the flame looked better. Can you describe what I'm looking for as I shorten it, or should I just shorten it by 1/8" and get another picture? The overhang is 1-13/16" in that photo. Is it best to use the choke to get a neutral flame while tuning the nozzle? Thanks again for the help.

Choke wide open. Choke adjusted to what I perceive as neutral. Sorry about the focus.

That's page 19 for anyone else who is following this.

Ha! That is what I thought I had cleared up in these two previous posts. My thoughts were that since the burner is tuned by the mig tip to mixing tube distance, sliding the choke the way I did keeps that relationship constant. Sliding it the other way effectively buries the mig tip into the tube as the choke is engaged. I misunderstood your answer. My first burner works the way that you're suggesting and I've always thought it was wrong. Oh well, that will be a very easy fix. I can do that tonight. Thanks for your input.

I'll be one of the oglers coming up to WY. to watch the eclipse. If you're really going to try to forge weld then, make sure that the horn of your anvil is pointed towards the eclipsed sun.

A friend of mine was doing that using a PID controller to keep the oil at temperature. He has since moved to a salt bath. I think that he is using bluing salts

Some flame pictures.

Hi ppancho, Not to answer for Mike, and I will be very interested in what he adds to this. I had luck with the slots as described above. Flame pictures coming soon.

I'm in the Denver area too and have been using the coal that you are questioning. It is a very clean bituminous and produces almost no clinker. I'm hoping that it stays available for a long time.

I was just camping this weekend and looking at the fire pit as we set up I thought 'there is a fair amount of charcoal sitting there'. Didn't want to deal with the mess, but I'm going to start gleaning charcoal when I'm done with a fire and it's convenient. Just stick it in a can and smother it.

I'll try to get some pictures up next week. Life is interfering with finishing the choke and nozzle even though there is so little to do.

I've been wearing a shade three face shield when looking into the forge at welding temps. I like it a lot, but have no idea how well it is blocking IR. If there is something better that is not just a rip off I would like to know about it. Fred, I'm a welder too and have stuck with the old school helmets. I don't even own one of the quick change helmets. When I use them at others shops they tend to confuse me because I end up flipping them out of habit.

I ended up with three 3/8" x 1.375" milled slots with the business ends squared. A total of 1.5 sq. in. or 250% of the 3/4 pipe area. I have not put the choke on yet but a quick test using my hand as a choke showed that this was enough porting, I would not go with much less though. I passed my copy of "Gas Burners for Forges etc." on to a friend a couple of years ago and do not remember how close this is to the designs in the book.

Thanks Mike, . I went looking for it last night and found the post that lead me to this conclusion. It's in the very first post of the thread. I will be making the slots bigger that this, but part of why I'm trying this is to see how much shorter I can make the back end of the burner. Also I got the idea from other parts of this thread that having a higher sideways velocity at the intake promoted more swerl in the burner tube to help mixing. As I said in my first post I already have a burner that is working fine for me. This burner is more to satisfy curiosity, and get my choke on the back side of the burner where it belongs. If it works better, that's icing on the cake.

Apology gladly accepted Frosty. Thank you.

I thought that the total area of the openings was to be at least 40% bigger than the burner ID area. Am I mistaken?

Thank you, thank you, thank you. In regards to the smaller air ports that I'm experimenting with. (This has nothing to do with the altitude questions that you answered so well.) The burner that I have been using was built before receiving your book and I pretty much figured that the larger the air ports the better. Some of the posts in this thread have made me want to experiment with that. On the experimental 3/4" burner I'm planning three 3/8" by 1-1/2" rectangular slots. Also on my first burner I have the choke sliding in from the burner side. I've seen the chokes either way, but I want to experiment with the choke sliding in from the gas supply side. Have you noticed differences either way.

Maybe if I try being more specific. Mike has stated that on his 3/4" burners he finds an .023 tip to be too small and a .030 to be too big. It would seem that the .023 would run on the lean side and the .030 would run on the rich side. Now, the altitude part. I would expect a burner that runs fine at 5,200' to run rich at 9,800'. It confuses me that the commercial burner manufacturer that my friend talked to recommended a larger tip for operation at high altitude. A larger burner makes sense to me, but not a lager tip in a 3/4" burner. I will be taking my burner up to his house in the near future along with some different size tips to experiment with. Just need to have our schedules match up and find the time. Thinking things out ahead of time is just part of the process. Mberghorn, your post came in while I was typing. Yes, I built my existing burner based on 'Gas Burners for Forges, Furnaces, and Kilns'. I bought the book and it arrived on the day that I completed the burner.

That's why I said "for a given amount of propane" I'm assuming that I would use less pressure for a larger orifice. Did you stop changing things on your burners when you got one that worked? (rhetorical). Thanks for the nice welcome.

Oooops. I meant to put the last post into the burners 101 thread. Sorry.

Hi, I'm new to this site. I accidentally posted this to the wrong thread, so I copied it to here. Sorry. I've been running a 3/4 Mikey style burner in a brick pile forge for about 3 years. I'm in the process of building another 3/4 burner with smaller air ports, from info that I got from this thread, just to see if I can tell a difference. I've been running a .030 mig tip orifice with good results. I'm at 5,200' Can anyone elaborate a bit on the sizing of the orifice? I'm going to be helping my friend (offgrid) with a forge that he will be running at high altitude , 9,800'. A commercial burner manufacturer who uses .035 mig tips in their standard 3/4 burners recommended to him that he would put an even larger orifice in that burner for high altitude. I have read both this thread, and the forge 101 thread and have not gleaned any info on how the orifice size is determined and how thinner air might effect this. Is orifice size just done by trial and error? Wouldn't a larger orifice result in a slower velocity, for a given amount of propane, and result in less air being pulled into the burner? I'm thinking that we will be wanting to pull more of the thinner air into the burner. Great thread! Victor

Hi, I'm new to this site. I've been running a 3/4 Mikey style burner in a brick pile forge for about 3 years. I'm in the process of building another 3/4 burner with smaller air ports, from info that I got from this thread, just to see if I can tell a difference. I've been running a .030 mig tip orifice with good results. I'm at 5,200' Can anyone elaborate a bit on the sizing of the orifice? I'm going to be helping my friend (offgrid) with a forge that he will be running at high altitude , 9,800'. A commercial burner manufacturer who uses .035 mig tips in their standard 3/4 burners recommended to him that he would put an even larger orifice in that burner for high altitude. I have read both this thread, and the forge 101 thread and have not gleaned any info on how the orifice size is determined and how thinner air might effect this. Is orifice size just done by trial and error? Wouldn't a larger orifice result in a slower velocity, for a given amount of propane, and result in less air being pulled into the burner? I'm thinking that we will be wanting to pull more of the thinner air into the burner. Great thread! Victor