Naturally Aspirated Ribbon Burner. Photo heavy.

[D.Rotblatt]

Thanks Frosty!

[Lou L]

Hello all!  Apologies for my disappearance (unless, of course, it was a refreshing change for you), but I just gave up on "interneting" for a while to focus on other things.  I've still been in the shop but not as much as I want to be until recently.  This winter I used my forge a number of times with no problems, but recently I've had an issue.  I fired it up to make my annual wine glass holders for my kids' teachers and had a new issue.  The stock is seriously oxidizing in the forge.  The section that is not red at the opening of the forge gets a black soot on it.  The oxidation was so bad on the smaller sections like the leaf and stem that it cracked and corroded terribly.  This forge has a decent number of hours on it and it has never done this before.

 

I have made no changes to the forge or burner since it lasted worked perfectly.  I even did some searching to find out if it was possible to get a bad batch of LP (maybe condensation in it or something) because I can't account for what caused the change in performance. 

 

Anyway, I have already been on here lurking for a day or two reading to catch up on what I've missed (a LOT) and trying to find an answer specific to a NARB.  I failed so here we are!

I wanted some advice on other people's experience with this and suggestions for best steps in problem solving.  I was thinking of a few first steps: bigger diameter mig tip,  mig tip moved closer to the mixing tube, covering one air intake (a big No-NO in Frosty world), or new LP cylinder....

I just can't get over the fact that this problem would arise randomly without a cause but I have not changed the setup...so I'm stumped...

 

I'm sincerely glad to be back reading and learning here....Once I logged back in I felt like I was missing close friends and family for a long time,

 

Lou

[ThomasPowers]

Remove and clean the orifice!  Insects, Micro spiders or joint tape can clog it.

[Buzzkill]

+1 on TP's suggestion.  Always check the easy things first!

[Frosty]

Good to see you again Lou, I missed you too.  Do you have any pics of it running? You know my usual, still pics, one in the opening right after you light it and another after it's warmed up good. Another set from the side to get a look at  the dragon's breath, again just lit and warmed up.

WHAT!? What kind of patently unblacksmitherly advice is "check the EASY things first" BUZZ? The EASY things?! Oh sure it's good advice but it's just soo unblacksmith! 

Okay, back to seriousness, (owww) a burner shouldn't change without doing something to it so I have to agree with bugs taking up residence. A NARB would be like a bug condo! I think I'd try taking it outside and firing it off till it gets good and HOT. Everything left by bugs except maybe mud dawbers should burn out and their dry little ashes just blow out the NARB. Sure, check the Jet and make sure nothing is living in the mixing tube but after than I'm thinking burning it clean might be your best bet. 

Burning bugs really stink so do it outdoors or the Missus will kill me too for suggesting it. 

Frosty The Lucky.

[Lou L]

I'll check the easy thing first tomorrow.  Sorry for following "unblacksmithy" advice Frosty, but I'm lazy!  I'm seriously annoyed by this development and would like to find schmootz in my jet to account for it.  I already used it for at least four hours and destroyed four wine glass holders in the process (the neighbors think they just look like weather Fall leaves but they disgust me).  I would think that the aforementioned bugs would be ashes already...but the jet is suspect.  I will admit that I use the forge without using firebrick to cover the front opening but I've used it that way since the start and had no issues.  I have firebrick on the way as another test variable.

 

I'll send along pictures if things are still haywire.  Seriously, has anyone ever had a bad batch of propane?  It sounds ridiculous but it's the biggest variable in the equation.  I used the forge recently without those issues and then changed to another cylinder.  The one difference I did notice is that the last time I used it it was much colder out and I had the cavitation sound upon first starting the forge.  This time it didn't do that but I chalked it up to the fact the weather warmed significantly in the two weeks.

 

Lou

[Frosty]

We'll let you slide Lou, you just delurked after a long absence so what the hey. 

I'll keep my fingers crossed for some kind of schmootz in the jet. I like easy fixes they so match my lazy nature. 

I don't think I've ever gotten a bad batch of propane but I suppose it can happen. Being a naturally skeptical character I sometimes lean into the suspicious. If it worked well when it was cold, (sub freezing?) but is a problem now it's warm it makes me think of water contamination in gas tanks back when I worked in a service station. Old cars had to deal with condensation in the tanks, modern systems pump more fuel that the engine can burn and it's circulated back to the tank, keeping it a couple degrees warmer than ambient so moisture can't condense in the tank. 

Anyway, water in the propane tank could have been frozen and just stick to the tank. Warm enough water melts and maybe? 

It's a reach as the propane tanks we use don't have a pickup at the bottom of the tank and that's where water would lay. Liquid propane is less dense and should float. So to speak.

Frosty The Lucky.

[Buzzkill]

18 hours ago, Frosty said:

What kind of patently unblacksmitherly advice is "check the EASY things first" BUZZ? The EASY things?! Oh sure it's good advice but it's just soo unblacksmith!

Just because I say it doesn't mean I DO it!  Even though it's something I've both heard and said since I was a kid, if I had a nickel for every time *after* I finally figured out the problem with something and it was one of the easiest things to try ........

Back to the topic though.  I think Mikey has mentioned a few times that sometimes propane tanks do get a gooey residue buildup inside that can plug gas lines or small orifices.  I haven't had this happen personally (yet), but that could give the equivalent of a "bad batch" or tank of propane.

[Frosty]

Ah, I'm with you on easy, BUZZ but it was an easy shot and my resolve is weak.  

Yes, Mike has said propane can leave a waxy build up as a potential problem in burners and said it many times. <sound of Frosty slapping his head> 

It'd be an easy fix, break the hose or copper propane line off the burner and clean it out with a torch tip file. Be sure to take a close look at the inside of the fitting while it's off too, there might be schmootz there too.

Good catch BUZZ.

Frosty The Lucky.

[Lou L]

Ok, I took some pictures as prescribed.  First I took apart the burner and cleaned out the jet.  Of course I ran a tiny piece of wire through it BEFORE holding it to the light and checking for obstruction because I'm not smart.  I DID blow through it to see if it was impinged and it may be my imagination but it "seemed" looser after the clean out...but this is one of those feel things where high hopes can change perceptions.  I lit the forge up, set it at my usual 7 PSI to get started and whipped out the camera.  Here it is:

 

This is the rather ugly forge right after lighting it up (fair warning: I'm not a "paint her up pretty" type of guy, I'm too impatient to get using the things I make to bother with aesthetics.)

 

This is the side view of the dragon's breath right at light up.  It is hardly visible.

 

I took two photos of the forge running at forging temps: one with the camera exposing for the flames so everything is darker and the flames can be seen, and one with a regular exposure so you can see the visible color of the hot forge.

 

And now the dragon's breath when running at forging temps:

 

While doing the photos I also shined up a piece of scrap and popped it in to see if it would rust while in the forge.  I saw nothing remarkable until I forged the end relatively thin.  The scaling wasn't terrible though.  Some blackish soot did build up at the edges where it didn't reach forging temperature but it came off easily when I wire brushed. 

 

This color impaired fool is looking forward to everyone's insights.  If the colors and flames look right then I have another working theory.  Is there as chance that, when the thinner sections were bent and closer to the burner, that I simply got them too hot and burned the steel?  I don't remember ever getting the steel white but, because I was working on four pieces at the same time, they did spend some time in the forge waiting for me to get to them.  The only oddity is that the last time I did this exact same project I followed the same exact process, made four at once, and ran the forge at the same pressures.

Here are links to some short videos I made of the thing running:
https://drive.google.com/file/d/1OY23Y30UtUccwl1YMUbK-LgXVVjQv4hx/view?usp=sharing

https://drive.google.com/file/d/1OQbb9bi-BmG9QCfFbvK9lBMO_BMAhkOl/view?usp=sharing

As usual, thank you all for your time.

 

Lou

[Another FrankenBurner]

The propane build up that Mikey mentioned is awful stuff.  I worked on a concession trailer which had issues with all of the propane equipment.  I ended up determining there was a flow restriction.  After testing everything else I could, I dismantled the fuel supply line into the trailer.  I found the 30 foot long 1/2 inch pipe completely filled with a yellow greasy waxy goo.  I believe it was the stuff they add to propane to give it an odor because it smelled like that's what it was.   I don't believe it was due to bad propane, just a long time of condensing this stuff in that section of pipe.  It only needs to partially plug the tiny orifice in a burner to change the flame.

When you say soot, are you meaning a fine dusty black powder?  Like when you place something over a candle.  

I have worked leaves really thin which then took too much heat afterward and scaled away.  I have also burned thin sections.  Too many irons in the fire?

Another thing which may have nothing to do with anything but when I work with the doors wide open like your photos, I see much more scale buildup than when the doors are more closed.

[Frosty]

It looks pretty darned hot to me Lou, maybe a LITTLE rich but good and close. It doesn't sound like you're describing an oxydyiing atmosphere either. Forged thin enough it could be burning and burned steel often looks like scaled.

The opening is awfully large and with the swirl your burner imparts in the forge atmosphere it's likely to induce a little ambient air in the bottom. A sill usually takes care of any ambient induction, something simple usually does the trick. Perhaps carve a couple inches of brick to match the curve of the chamber and just lay it in the opening. The sill will redirect the portion of the swirling flame contacting the forge wall back inwards enough to clear and breaks up any induction forces. 

All in all I like it.

Frosty The Lucky.

[Lou L]

I will be getting firebrick tomorrow.  I could likely lay one brick on the side in front of the opening and it would be high enough to act like a sill.  If not I'll be placing a brick in front anyway in an upright position that will allow it to cover the entire opening if needed (but not needed).  I intend to cover the small back opening unless it is needed.  I purposely created a shelf for supporting a brick in the back.  Would that cause a back pressure issue do you think?  I know I will need to do it for welding but I haven't welded in the forge yet.  I'm hoping to be able to weld at ridiculous low pressures.  I am going to try it at 7 PSI (what you saw above) but with the openings covered.

 

Either way, I'm so far quite happy with my burner.  I'm ready to start making some more of them with the mold I made for this one.  I want to see if I can get repeatability.

 

Thanks!

 

Lou

[Frosty]

That should do it nicely. If you can't weld in that then you're doing it wrong. 

Frosty The Lucky.

[Matt NZ]

So here is my attempt at a NARB. 

 

133 holes at 4mm. We used mails with the heads cut off to form the burner holes. The refractory was probably a bit green when we pulled them out as some nails chipped the top surfaces as they were removed but it still works fine.

This is it running at 5PSI

 

This is running inside the forge at 5PSI. The refractory was still curing so we didn't run it for long

 

[Frosty]

Nice even flames! Well done, A little rich maybe, it shouldn't have the blue flame drifting out the opening but that's just a little tuning. Easy peasy. Don't sweat the orange in the flame that's the calcites in the refractory oxidizing. 

A few chips in the outlets of the holes shouldn't make much if any difference. 

Nice job, I like it.

Frosty The Lucky.

[Matt NZ]

On 7/13/2020 at 5:12 PM, Frosty said:

Nice even flames! Well done, A little rich maybe, it shouldn't have the blue flame drifting out the opening but that's just a little tuning. Easy peasy. Don't sweat the orange in the flame that's the calcites in the refractory oxidizing. 

A few chips in the outlets of the holes shouldn't make much if any difference. 

Nice job, I like it.

Frosty The Lucky.

Thanks. You guys did all the hard work figuring out how to get this far

How would recommend tuning it? Just trimming down the mig tip to get more air in? Its a home made T burner from 1" pipe and a 3/4 pipe as we couldnt get a reducing Tee.

 

I fired it up again tonight and this thing is hot! The whole forge internals are glowing at 4-5psi after 10minutes. Happily sat there for over an hour.

 

If I turn it up above 15PSI it hums like what Dan's did

[Frosty]

I don't get your description of a T burner made from a 1" pipe and a 3/4" pipe. I can't envision that, have a pic? 

Yes, the way I tune a T burner to increase the air in the mix is by trimming the mig tip. 

Frosty The Lucky.

[cbrianroll]

Boy, I've been away too long...so much more info now!

I need..want...to upgrade to a ribbon burner I think. Currently running a frosty ³/4 t burner in a 25lb propane tank forge. I may have missed this so please excuse me if so...can I convert that to fit the plenum? Is tube length needing modified?

Thanks

[Frosty]

I didn't change anything about the T. I welded a thread protector to the plenum port, the burner just screws on, easy peasy. 

Frosty The Lucky.

[cbrianroll]

Thanks Frosty, I was hoping it was that simple!

[Frosty]

Putting the T on is, it's getting the rest balanced and working that's a tetch trickier. A number of guys have made versions that make mine look primitive. 

Frosty The Lucky.

[cbrianroll]

Yeah, that's above my pay grade lol....I've got reading to do.

[Frosty]

HAH, I haven't had a pay grade since retiring! Now, get ye hence and TINKER! 

Frosty The Lucky.

[cbrianroll]

Yes sir lol. I'll be back with a progress report hopefully sooner than later.