Naturally Aspirated Ribbon Burner. Photo heavy.

[Mikey98118]

Frosty,

As you have pointed out, pictures and videos of flames can be tricky to judge. but it looked even better than the flames on the fan blown versions, for my money. In fact they looked like miniature versions of my best flames, you dog! talk about have your cake and eat it too...

[Frosty]

Thanks Mike, I burned a lot of 2" x 4" test blocks looking for a final fuel air velocity that was just above it's propagation rate. This one has 19 crayon (11/32") nozzlettes. I put 21 in the test block and it back fired after about 15 seconds so I plugged 2 and this is what I got.

I was thinking those flames looked an awful lot like the flames you liked.

When I tested the second cast refractory burner I turned it down till the gauge was bottomed on the stop and the flames were stable till the gas stopped flowing. The thing barely pops when I shut it off. I'm so jazzed this design isn't a fluke with v1 v2 works just as well.

I'm glad I like cake, this one is a bakery full.

Frosty The Lucky.

[Mikey98118]

I would still like to see a permanent thread on this forum, which is dedicated to topics like ribbon burners and other kinds of ceramic burner blocks, and feel like this would start it off with a bang! It is very disturbing to see blacksmiths newsgroups and the home casting groups withering away; I feel protective of those that are left, and the best answer I can think of to make sure this one stays afloat is to do as much as possible to help keep it interesting, and easy to learn from.

 

[Frosty]

Well, we can ask Glenn or Steve to establish a subsection under gas burners, say "Multi-port burners" With two sub, sub? sections, guns or blown and naturally aspirated.

I almost have the new 2 NARB forge built, As they always do it's more complicated than I expected but it'll have a full 2" of kaowool under the Kast-O-Lite 30 and Zircopax flame face.

I'll shoot pics as I remember to take the camera out. I don't know if the forge itself will be anything to talk about the burners are the stars.

Frosty The Lucky.

[Mikey98118]

I expect the forge will be something to talk about too. Yes, a burner is just one part of a forge, but radically different burner designs change forge capabilities just as radically. Mind you, if I was young and in my prime I'd be aflame with jealousy. But since I'm old and tired there is just a big happy grin planted on my mug

[Frosty]

Oh come on, it's just an insulated box intended to keep 2,600f+ fire in. What's so special about that?

The way the burner ad life is treating us I'm kid of rushed on the forge itself. My biggest challenge is in not trying to add every bell and whistle I can think of. Just today I remembered to put pass through doors in it. I'm hoping to get it running for Saturday's club meeting and hoping I don't screw it up too badly.

Frosty The Lucky.

[Buzzkill]

Just curious, have you used the burner in any other orientation?  I wouldn't expect it to perform differently, but I'll probably do a side or bottom mount if I make one of these.

[Mikey98118]

All three positions have been successfully employed with ribbon burners.

[TFT]

6 hours ago, Mikey98118 said:

All three positions have been successfully employed with ribbon burners.

What about a forge that is made up of only mutli port burners(burner ports on all surfaces)? That seems like there would be an issue with exaust size... 

Im just saying. I dont think ill be trying that but it would be a sight

[Frosty]

Yes, multi port burners are used in all orientations. Building a forge with burners on all walls would be an interesting exercise in orienting them so one flame didn't interfere with others but sure, why not?

Making sure burners are oriented and forges are vented sufficiently to prevent too much back pressure is normal to any gas fired furnace.

Go ahead experiment but save a few bucks and do it in brick pile forges. Once you have an orientation that works is time to build a more permanent forge that will take high temperatures better than fire brick. This is what I do as the pics of the NARB testifies, I don't let them get past high orange though, the soft insulating fire brick available here is only good to 2,200f and degrades very quickly at forge temperatures.

Frosty The Lucky.

[TFT]

Maybe after i make a NARB ill try a few but im in the crowd that only uses 1 20# tank and 4 burners would freeze my tank up real quick(thinking of making a 2 tank manifold this winter)

[ede]

" the vibrator I made to settle the refractory into the mold and the expanded sheet thoroughly. It's just a piece of 5/16" rd. with about 4" bent 90* at the end. With the drill turning at a moderate speed it vibrated every bubble out quickly and also quickly produced free moisture at the top of the mix and through a joint under one end of the mold"

 

Hey Frosty,   

What are your thoughts on putting the plenum with wet castable under a vacuum bell jar and run a vacuum to pull all of the bubbles out?  People who do lost wax casting generally take the bubbles out of investment (like a plaster of paris) before doing burnout of the flask/mold.  My thinking is that it might create a stronger bond with no air pockets between the castable refractory.  Of course one would need a very large bell jar but one could always fab a smaller plenum for a smaller forge.  A rod knocker seemed to admirably fit the bill for you though. 

It's good to see your approach to a ribbon burner.  Nice work.

[WayneCoeArtistBlacksmith]

I am very excited about Frosty'S work on the Narb.  I THINK that it is a great improvement over the NA burners with only a 3/4" flame.  As much as I like it I think that it lacks the ability to control the gas/air mixture of a blown Ribbon Burner.  I favor the NARB WAY OVER a standard NA burner.  Given the choice, for just blacksmithing I would go with a NARB but if you want fluxless welding, general blacksmithing and heat treating I would chose the blown Ribbon Burner.  Maybe Frosty's NARB  as shown in his pictures (I think that this shows a VERY reducing flame) with baffles for air control might work as well as a blown burner.

We see many posts here where nubies put forward new ideas that people with more experience know won't work well.  However, when someone with Frosty's experience not only come up with new ideas but then does the study to prove the concept I tip my hat.  Congratulations and thank you Frosty.

This is not to say that beginners should not put forward questions or new ideas.  With these more experienced smiths can check it out and if the beginner doesn't do the study or experimentation maybe the more experienced will get a new inspiration and do the background work/

Let me know if I can help you.

Wayne.

[basher]

I am reading this with great interest, the amal gas air mixers I use supply a short choke mixer for use in ring burners, my imediat thoughts were that this would cross over to ribbon burners as well. I have had one sittingaround for a year  waiting for time to have a play.

 are these burners quieter than your non ribbon burners?

 I am becoming more and more fed up of losing my voice over the roar of gas forges.

 

[jlpservicesinc]

Brilliant  work there Frosty.. Just excellent.....

[Frosty]

You guys are making me blush. Uh let's see, in order:

Ede: I'd take credit for the bent rod vibrator but it's an old concrete trick I learned in the soils lab days. A vac chamber would work a treat but it'd be kind of expensive wouldn't it? If anybody makes a vac chamber, please let me know so I can be out of town when you test it. Implosions are nasty things to be near and harder to predict.

Oh heck Wayne you're really making me blush. I only adapted known tech to John's ribbon burner build plans. Then did a little tweaking and basic experimenting. I wouldn't have even tried if someone hadn't posted links to commercially made multi port burners used by the glass blowers.

I don't know what you mean by "baffles" to control the fuel air ratio? Granted it's easy to control on a gun burner just turn the psi up or down and not change the blower output. The NARB appears to be running a lightly reducing atmosphere now a shined up piece of steel stays shiny till it's bright red and never scales in the fire. the couple times folk have tried welding in it haven't had trouble. Nobody's tried a fluxless weld in it though and that'll have to wait till I get the burners pulled farther out.

We ran it hard this weekend with the front mostly closed with my adaptation of Mike Porter's "thermal baffles". After about 3 hrs the right side burner started backfiring So I shut it down. And in less than 30 minutes the other side started backfiring so I shut it down and closed up the tank valve.

Inspecting the plenums the welds I'd ground were dark blue meaning the blocks were overheating. I'll have to move them farther out of the chamber.

Owen: Ribbon burners are multi port burners as are button, block, ring and any number of burner shapes. If I'm not mistaken the gas air mixers you're talking about are used to drive multi port burners as a matter of course.

And oh YES they are quieter, Tristan's 1/2" T burner about 20' away across a busy shop was louder than my 2 ribbon burners driven by 3/4" T inducers 5' away. They're a long way from silent but significantly more quiet you only have to raise your voice a little to talk say a quiet cocktail party level.

Thanks JP though I shy away from calling it brilliant I just adapted and tweaked existing designs and John Emerling's good home build.

Frosty The Lucky.

 

[WayneCoeArtistBlacksmith]

I don't know what you mean by "baffles" to control the fuel air ratio?

Frosty, I guess I used the wrong word.  I'm talking about a disk (or square) piece of metal that could use a small screw to rotate over the burner Ts to partially restrict air flow, thereby controlling the air/gas mixture.

[stockmaker]

Hello Frosty,  I too am reading this thread with great interest.   I have another question or two about the Plenum/Burner build for your NARB.  I am doing some preliminary planning to build one by re-reading your post's and realized that I don't know how much air plenum is left in the plenum after the burner (refractory with holes) is installed.  It looks like the 2" thick burner block goes about 3/4" to 1" into the steel plenum box.  Is that true?  In your opinion is this measurement critical to the tuning of the NARB?     

Is this fun or what!

[ThomasPowers]

Funny most of the stuff I have read was on how to put bubbles into the refractory to increase it's insulative value.  But I am NOT an expert in this area by any means!

[Frosty]

7 hours ago, WayneCoeArtistBlacksmith.c said:

I don't know what you mean by "baffles" to control the fuel air ratio?

Frosty, I guess I used the wrong word.  I'm talking about a disk (or square) piece of metal that could use a small screw to rotate over the burner Ts to partially restrict air flow, thereby controlling the air/gas mixture.

We've been calling that control a "choke" whether it's a screw down plate like you describe of a sliding sleeve like Mike puts on his burners, a swing gate, etc. It derived from the automotive version of these things a carburetor choke which limits air intake just like wrapping your fingers around THAT bosses throat.

I tune the T so it doesn't need a choke increasing or decreasing the gas psi increases and decreases the air intake proportionally on a nearly flat curve. My preference is a SLIGHTLY reducing flame, I've had steel stick together in my current shop forge by accident but I've never tried welding without flux deliberately. It shouldn't be a problem if scale isn't forming in the fire.

If a person wants to choke a T a little strip of aluminum foil or even masking tape partially blocking one air intake port will richen up the flame.

Stockmaker: That's a good question and I'd have to measure it to give you a definitive answer. I removed one side of the tubing with my bandsaw so there is no rough corner "tooth" for the refractory to grab so I welded a short strip of expanded steel to the long edges. I only pressed the plenum in till it was maybe 1/2" into the refractory but there was displacement and after vibrating the refractory actually rose a little.

I recently found a finer piece of expanded in a different stock pile and would've used that instead but they're done now. The other good alternative especially if you don't have a large enough cut off saw. The ribbon burner plans Wayne has posted on his web site by John Emerling cut the open side with a torch. This leaves an edge that is 90* to the plenum's side and a little ragged. This provides good "tooth" for the refractory to adhere to.

Using a torch to open one side of the tubing might mean you must use larger square tubing than I did. I used 2" x 2" but John's plans call for 3" x 3".

I'd have to take the burner apart to find out how much of the Approx 1 3/4" ID of the 2" x 2" sq. tubing I used has been taken up by refractory. It's a good question and I'll have to see what I have to measure depth around a corner. I have to reposition them in the forge anyway I might as well. Eh?

Thomas: I'm with you, air entrainment is a science in the concrete industry with special chemicals to control it, especially in hard freeze country. The main reason I vibrate the Kast-O-Lite isn't to "degas" it, it's to vibrate it into all the nooks and crannies in the mold, especially around the crayons.

I gave some half joking thought to using carbonated water in the refractory to cause bubbles or maybe including a % of soda. I don't know about the soda it could well mess up the chemistry and my #1 need is the refractory be HOT resistant.

I haven't made refractory in a LONG time, heck I still have the better part of the last bag of fire clay I bought 20+ years ago along with the masonry sand. I still need to clay my barrel stove but I'd have to REALLY clean it and that's a lot of effort for a lazy fat old guy. I've messed with different void generators in refractory the most common being saw dust that gets burned out on firing. I gave thought to using bean bag chair beads but haven't seen a bag in a long time. Nice spherical voids would make for a stronger brick, liner, etc. than saw dust's irregular often sharp, splintery shape. Grinding saw dust to powder in a blender doesn't make particularly effective insulating brick. Believe it or not Angle hair pasta broken into pieces as long as it is wide worked surprisingly well.

Ah, there I go side tracking again.

Frosty The Lucky.

[ede]

On 11/14/2016 at 11:26 AM, ThomasPowers said:

Funny most of the stuff I have read was on how to put bubbles into the refractory to increase it's insulative value.  But I am NOT an expert in this area by any means!

My ass-umption was that you want insulating properties or air pockets if it's used as a forge liner/hard face, but in this case since it's a manifold to send the gas through multi orficies, that less air pockets would be better for structural integrity.

I"ve used a vacuum table extensively for vacuuming investment as a step in the lost wax casting process.   Maslow's law of the hammer strikes again!  

 

 

I had read the following on Wayne's site:  special castables (the Kast-0-Lite does not work well for this) needed for casting the Ribbon Burners.  

While on Emmerlings directions on step 6 says other refractories can be used.  Wayne, can you tell us what make Kast-O-Lite not work well for this?  

[WayneCoeArtistBlacksmith]

ede when I tried casting using the Kast-0-Lite it broke apart on me.  I have not tried Frosty's method.  The castables that I use are much tougher but maybe I just did not use the best procedure.

[Frosty]

Ede: Reading Wayne's experience with them breaking up is why I added the expanded metal as rebar. Not knowing better than reading some of the setting and curing characteristics of Kast-O-Lite I made a guess and treated it like reinforcing construction concrete. For maximum strength you don't want rebar parallel or perpendicular to long sides. However you do want bar parallel to known directions of stress. Okay, that's more info than is useful here.

In a monolithic pour with general stress as in thermal expansion, contraction, the better orientation for rebar is at angles OTHER than 0 or 90 to faces. This is true especially in things like cast refractory. A piece of reinforcing that runs in a straight line along or across an edge causes a zone of either lesser or greater stress when it moves. If on the other hand it zig zags the tensile & compressive stresses damp each other.

Expanded metal being a series of diamond shapes twisted from the plane are nothing but tooth for the material to bond to and are unable to conduct stress more than 1/2 the length of a straight edge of an opening.

John's plans call for the sq. tubing to be opened on one side with a cutting torch. The torched edge provides excellent tooth but the outside corner is just one long straight line parallel with the outside face of the cast block. Combine that with the greatly different COE between the steel tubing and the refractory and the forces trying to move things are huge and seeing as cast refractory doesn't have any flex it's what's likely to fail.

The only reason I vibrated the mix into the mold is because I mixed it as dry as I could get away with and it couldn't flow and fill the voids around corners and crayons. Vibrating wasn't to remove air it was to cause liquifaction so it'd fill the mold without voids.

Frosty The Lucky.

[JHCC]

IFI member Branstetter has come up with an interesting variation; see http://www.iforgeiron.com/topic/49154-my-new-forge/

[Frosty]

Hey gang: It's been a while since I mentioned progress and or results with the NARB. The last time I ran it at a meeting I had the reg set at about 2-3 psi. I was happy to see two 3/4" T inducers making good heat but a 40lb. propane tank not even sweating so it was drawing very little for the output. That was a pleasant result.

After about 3 hours though the left burner started backfiring, burning back into the plenum and then out the T. I couldn't get it to correct and had to shut that burner down. Within maybe 15 minutes the other burner started backfiring and I shut it down. 

What appears to have happened is the burner block got hot enough to speed the rate of propagation of the fuel/air above the speed of the mix exiting the outlets so the fire burned up the outlets into the plenum.  

Either I can try shielding the burner block from the forge heat or try increasing the fuel air flow and maybe keep it cooler.

It's too cold to do much messing around in the shop till later in the year. I'll let you know what I find out.

Frosty The Lucky.