Naturally Aspirated Ribbon Burner. Photo heavy.

[Lou L]

All, I hope you understand that I posted the idea as an exercise (which I will act upon if a realistic option comes out of this) and, in no way, did or do I think my suggestion was viable.

Still, as usual, the experts on IFI came through.  I sure am glad I only spent a couple minutes on that drawing!  I assumed that I was creating complex air issues with the idea but I had no idea it would involve that many variables.  I had considered using a small air pump (think fish tank) and using 1/4” copper tubing to feed more air through the existing inlets.  In reality, I just want to determine if more air volume is beneficial   Now I’m thinking that it may make more sense to experiment by changing the geometry of the air inlet first.  I honestly don’t know but this is how I learn: Theory, concept, seminar, then experiment.

For me, learning the how and whys of the NA burner through a discussion like this is WAY better than just building by Frosty’s design and using it without really understanding how it works. 

I sincerely thank you for entertaining my juvenile foray into this.  I just coached my sons baseball team earlier today (all 5 and 6 year olds) so I know how you feel.  I felt like Lou Gehrig in my baseball skills standing next to them....

 

[Frosty]

6 hours ago, Exo313 said:

What about birthday candles? I'm thinking about trying them; one would think they would melt out rather easily. They also come in a couple different diameters, which appeals to my desire to tinker...

Might work but they're smaller Dia than crayons so you'll need more of them. I found that you can't do a straight calculation of the cross section area from one to another or I would be using fewer crayons to match a 3/4" burner tube. Do the calculation and use that as the departure point to do your experiments.

Frosty The Lucky.

[Latticino]

I believe that the reason you can't do a simple proportion for the relative areas is that boundary layer effects come into play.  Think about it this way:  assume for a given crossection flow velocity there is a layer adjacent to the pipe/duct walls where the fluid flow is essentially stagnant due to friction with the wall.  This layer may be quite thin, but it has an influence on the rest of the flow in the duct as well, making the velocity non-uniform in the pipe (see below).  Needless to say, this is different depending on whether the flow's Reynolds number indicates flow is turbulent or laminar, as seen below, but that is another issue and I'm not going to divert that far.  Bottom line is that if you change the pipe crossection from one relatively large pipe to many rather small pipes the boundary layer has more effect on the available flow crossection area of the latter much more than the former.  If you cross over from turbulent to laminar flow (by slowing the velocity down a lot) there is a vastly greater effect, but I believe that will be unlikely for the fuel mixture flows we experience (but I don't have time to do the math now to figure that for sure).

 

[Frosty]

14 hours ago, Lou L said:

All, I hope you understand that I posted the idea as an exercise (which I will act upon if a realistic option comes out of this) and, in no way, did or do I think my suggestion was viable.

Still, as usual, the experts on IFI came through.  I sure am glad I only spent a couple minutes on that drawing!  I assumed that I was creating complex air issues with the idea but I had no idea it would involve that many variables.  I had considered using a small air pump (think fish tank) and using 1/4” copper tubing to feed more air through the existing inlets.  In reality, I just want to determine if more air volume is beneficial   Now I’m thinking that it may make more sense to experiment by changing the geometry of the air inlet first.  I honestly don’t know but this is how I learn: Theory, concept, seminar, then experiment.

You don't need to be so self deprecating Lou. I think about weirder stuff all the time and talk about on the occasion I find someone willing to listen. It's all good and who knows we might come up with something that works. Even if it doesn't work well as a forge burner it might be just the thing for something some other wild thinker comes up with. A good brainstorming conversation is always a good thing worth doing.

5 hours ago, Latticino said:

I believe that the reason you can't do a simple proportion for the relative areas is that boundary layer effects come into play. 

Oh cool, somebody who actually can do the math! I'm not good enough at math to do the fine calculations but I'm really good at intuitive stuff. To restate your comments in plain if not accurate English. The cross sectional area is a geometric progression, linear changes in dia. mean area changes are squared. 2xD = 4x area. Circumference is a simple multiple.

So yes, reducing the diameter means the flow is reduced by the square of the change while skin friction is reduced by the fraction. Half the dia and there's 1/4 the flow and 1/2 the tube wall so the ratio is significant. 

Worse, as smooth as it gets Kastolite isn't as smooth as steel pipe to it generates more friction.

I even tried increasing the number of crayons based on surface contact of the mix flow. I drilled a lot of holes in  2 x 4 pieces testing.  

Frosty The Lucky.

[Patterson Forge]

Frosty, your mention of paper straws has me thinking: use tightly wound paper. Take a sheet of newspaper and start the roll on a toothpick. Once the roll has been started remove the toothpick. Keep winding the paper to the size you need, then cut tape trim. Should work very well.

[Frosty]

29 minutes ago, Patterson Forge said:

Frosty, your mention of paper straws has me thinking: use tightly wound paper. Take a sheet of newspaper and start the roll on a toothpick. Once the roll has been started remove the toothpick. Keep winding the paper to the size you need, then cut tape trim. Should work very well.

News paper doesn't work, printer paper is stiff enough it works nicely. Keeping it together while you cast it is a problem it absorbs water and moves around and the binder in the refractory fossilizes it. Waxed paper is too limp and butcher paper didn't work very well.

Good idea though, I thought so I just didn't get it to work I just might've been doing it wrong.

Frosty The Lucky.

[Daguy]

9 hours ago, Frosty said:

News paper doesn't work, printer paper is stiff enough it works nicely. Keeping it together while you cast it is a problem it absorbs water and moves around and the binder in the refractory fossilizes it. Waxed paper is too limp and butcher paper didn't work very well.

What about Pixie Stix?  The candy?  Comes in waxed paper straws.  Give the candy to the grand-kids and use sand as a filler.

[Frosty]

7 minutes ago, Daguy said:

What about Pixie Stix?  The candy?  Comes in waxed paper straws.  Give the candy to the grand-kids and use sand as a filler.

Fill the grand kids up on sugar and send them home eh? Revenge is sweet.

Might work a treat I stopped looking when I decided crayons worked well and don't cost much at the dollar store. Heck I'm too lazy to even peal the wrappers off.  I'm not going to start making them on a production basis and what I'm doing works. 

Just don't stop bouncing ideas off me if you come up with something easier and cheaper I might give it a try. I'm thinking of making another pair and another forge, I'm not satisfied with the forge I made last time.

Frosty The Lucky.

[Daguy]

2 minutes ago, Frosty said:

Fill the grand kids up on sugar and send them home eh? Revenge is sweet.

As Khan said in the Star Trek movie, "Revenge is a dish best served . . . ".

 I think he went on from there, but that's the important part.  

BTW, Nice pun.

 

[SaltCitySteel]

On 5/10/2018 at 1:15 AM, Frosty said:

Fill the grand kids up on sugar and send them home eh? Revenge is sweet.

Might work a treat I stopped looking when I decided crayons worked well and don't cost much at the dollar store. Heck I'm too lazy to even peal the wrappers off.  I'm not going to start making them on a production basis and what I'm doing works. 

Just don't stop bouncing ideas off me if you come up with something easier and cheaper I might give it a try. I'm thinking of making another pair and another forge, I'm not satisfied with the forge I made last time.

Frosty The Lucky.

Frosty have you been able to get the ribbon burner as hot as your standard T burner or is it slightly cooler with more even heat?

Mike B

[Frosty]

Welcome aboard Mike, glad to have you. If you'll put your general location in the header you might be surprised how many of the gang live within visiting distance.

Yes. It's more stable than the single outlet burner so it isn't as effected by back pressure or external breezes so they run fine in much smaller volume forges. The flame velocity is lower as well so the fire stays IN the forge longer. 

I"m quite pleased with how well the things work.

Frosty The Lucky.

[SaltCitySteel]

Sounds good I will be building one once my kast o lite 30 gets here!  

-Mike B

[Irondragon Forge ClayWorks]

While you are waiting for supplies, I suggest reading this thread it will help getting the best out of the forum.

https://www.iforgeiron.com/topic/53873-read-this-first/

 

[Jbradshaw]

SaltCitySteel to Frosty's point about local members. I'm guessing you're in the Syracuse area based on your username. I live in Camillus.

 I have built two of these burners, but haven't gotten around to building a forge for the one I kept yet. If my assumption above is correct I can show you the one I still have ( I gave one away to a friend in the area). It could save you the (very limited) work of making the form by using the one I already made. 

[SaltCitySteel]

Bradshaw I'm in Camillus too.  My forge is in Auburn though.

-Mike B

[SaltCitySteel]

15 hours ago, Irondragon Forge & Clay said:

 reading this thread will help you get the best out of this forum.

 

 

Thank you Iron Dragon,  Just read it.  Very helpful.  I was commenting using my phone initially which was a little more difficult than the computer I am using now.  The google search including the phrase iforgeiron is a great help.

-Mike B

[Jbradshaw]

 

2 hours ago, SaltCitySteel said:

Bradshaw I'm in Camillus too.  My forge is in Auburn though.

-Mike B

Mike I'm thinking we met in April at the NYSDB meeting. If you want to check out the burner, or get together otherwise, let's take it to the DM function to not clutter up this thread. 

Jonathan 

[CreekSideForge]

Hey Frosty, I have a quick question. Currently, I have a coal forge and a JABOD charcoal forge that I use to mainly make knives and other things. They work wonderfully for regular work and forge welding, but they're more difficult to use for heat treatment mainly due to having inconsistent heat and/or heat control. Therefore, I would like to build a gas forge to help with that problem. It would be out of a 20 lb propane tank out of the style of Wayne Coe, 2 layers of kaowool, kastolite,etc. The heat treatment would involve a baffle tube also. 

My question is: would you recommend a ribbon burner or a regular single port burner ? (I plan to use your T-burner or the NA ribbon burner)

[Frosty]

A ribbon will give more even heat over a length. How many to use depends on the volume and shape of your forge. The forge plans on Wayne's site are sound and proven. 

Frosty The Lucky.

 

[blacksmith-450]

I just finished assembling my ribbon burner. At a low pressure of gas and air, small flames form well.

When I increase the pressure, the setting gives a flame a little soft and without a great velocity... and if I add a little more air, the burner blows out.

Is it possible that my holes are too small? By drilling them bigger, would it give me a margin of adjustment?

[Canlib]

I was seeing similar results on early firings of my burner because the cast block of refractory was still damp.  And then of course there is the "don't try to tune the burner outside the forge" thing.

[blacksmith-450]

1 hour ago, Canlib said:

And then of course there is the "don't try to tune the burner outside the forge" thing.

Perfectly agree !

[Frosty]

It's a gun burner yes? This one needs to be turned down. The flames are also  really rich. You have more blower than that burner can use wide open.  You don't drive with the gas pedal floored do you?

You only put 15 ports in it, who's plans were you following? I put 21 in my naturally aspirated version. Chasing the holes larger should help let you run at a higher throttle but too large and it will burn back into the plenum.

You are aware of how little pressure a NA burner produces yes? A gun blower is driven by a blower so you aren't limited to finding the delicate balance I had to, there is a LOT more adjustment possible. You can just tune your blower and propane to make that one work or make more till you find what you like. 

Frosty The Lucky. 

 

[blacksmith-450]

Thank you Frosty
Yes I have a little blower of fieplace to run the burner. I will lightly drill over the holes and lower the air volume to a minimum. I will add photos later. 

[SaltCitySteel]

Frosty-

thanks for all the info.  Got her all setup. 19 holes using Wendy's straws. Reaches forge welding temp at 10psi without itc100.  It is just heating up.  Once I do the final coats I'll upload another pic.

i did a bit of machining on the T burner I made from your plans.

 

-Mike B.