Andy's "D" forge

[Mikey98118]

Andy,

I am answering your email here, because for some reason I have no response feature (first time for everything) on my end of the email program (I am suffering through a lot of sudden glitches with email today). I encourage you to post your videos and questions to the group, and simply delete your kind words to me in particular.

As to what I get from the videos:

(1) Judging from the color ranges shown by interior surface incandescence on a forge running with one end wide open, your burner can't be running all that problematically!

(2) Do not close that open end before you shove your burner's flame nozzle back within the burner opening at least 1/2", and a full1" would be better; otherwise the the nozzle is likely to melt. Ditto advice for using any high-emissive coatings, before retracting the burner.

(3) As best I can tell, you have a nice flame coming out of the burner; as to why it goes white sometimes, I don't have a definite answer having never seen this before, but if I had to bet, my money would be on some kind of gunk in the gas jet; possibly from the gas pipe the jet is mounted on, or even from the fuel hose; you indicated you had not run the forge much, so it may clear itself out without any help.

Let other eyes view your videos, because you have nothing to feel self-conscious about in that forge. Don't  be surprised when someone suggests that you change the burner's aim so that the flame strikes about the middle of the forge's floor. Yes, you still have some problems to work out, but I think you're doing a lot better with it then you might think; with a little tweaking I predict it's going to end up being a very hot little forge.

 

fussy old  doc Frankenburner 

[Frosty]

I"d like a look please.

Frosty The Lucky.

[Andy98]

On 9/10/2016 at 10:35 AM, Mikey98118 said:

Andy,

I am answering your email here, because for some reason I have no response feature (first time for everything) on my end of the email program (I am suffering through a lot of sudden glitches with email today). I encourage you to post your videos and questions to the group, and simply delete your kind words to me in particular.

As to what I get from the videos:

(1) Judging from the color ranges shown by interior surface incandescence on a forge running with one end wide open, your burner can't be running all that problematically!

(2) Do not close that open end before you shove your burner's flame nozzle back within the burner opening at least 1/2", and a full1" would be better; otherwise the the nozzle is likely to melt. Ditto advice for using any high-emissive coatings, before retracting the burner.

(3) As best I can tell, you have a nice flame coming out of the burner; as to why it goes white sometimes, I don't have a definite answer having never seen this before, but if I had to bet, my money would be on some kind of gunk in the gas jet; possibly from the gas pipe the jet is mounted on, or even from the fuel hose; you indicated you had not run the forge much, so it may clear itself out without any help.

Let other eyes view your videos, because you have nothing to feel self-conscious about in that forge. Don't  be surprised when someone suggests that you change the burner's aim so that the flame strikes about the middle of the forge's floor. Yes, you still have some problems to work out, but I think you're doing a lot better with it then you might think; with a little tweaking I predict it's going to end up being a very hot little forge.

 

fussy old  doc Frankenburner 

Thanks Mikey - I found that very encouraging. As I mentioned in my post above, I have actually used the forge now - which was great, although I discovered exactly how much of a wuss I am with a hammer.

Regarding the flare: There is none. The burner mixer tube is setback approx 3/4" from the interior of the forge, with the forge lining shaped into somewhat of a flare/nozzle. Here is a photo of the burner opening from the top half of the forge when it was removed:

...the burner isn't installed in the photo, but if it was you wouldn't be able to see it - it's set back a little further than the angle would show.

I realize the flare/nozzle is not the correct taper - I was worried about losing too much insulation depth. Do I need a flare? Now that I have the forge actually going, and now that I have an anvil, I am in a position to make one - or at least attempt to.

The mixer tube does show some temper colours on it, so it must be getting hot. The temper colours extend just a little but further back past where the pipe-threads end. I can take a photo if that's useful. 

The external part of the tube remains cool to the touch while in operation, but it does get hot after I shut the burner down - I can't say when the temper colours appeared.

I can try pulling the mixing tube back some more. I'm paranoid that the gas will choose to go into the forge shell, rather than the forge interior, if I pull it back too far.

Advice and comments are appreciated.

[Andy98]

EDIT 1: I keep trying to post the forge videos I sent to Mikey, but the forum keeps eating my work. Frustrating. I'm going to keep trying...

EDIT: 2: It seems that the forum is rejecting posts with youtube clips embedded, but is accepting them as regular links....

On 9/11/2016 at 1:06 PM, Frosty said:

I"d like a look please.

Frosty The Lucky.

Certainly!

The video below shows the forge running at a variety of exposures. The forge would have been running for only a few minutes at this point:

https://www.youtube.com/watch?v=cRuXz102jqw

I then decided to wait until it got darker out, and I turned off the forge and returned approx 40 minutes later. The forge had obviously cooled off, and this is what it looked like when I restarted it. I see a lot of white flame at the beginning, which might be partly due to exposure on the camera, but it seems to go away so perhaps that was just due to the forge being cool?

https://www.youtube.com/watch?v=FG-JC_JXQoo

...and finally the last video of the night. The forge only ran for a total of about 5 minutes really:

https://www.youtube.com/watch?v=fIapN5f7K38

On a side note, just in case it's interesting to you, I build the forge aiming for a D shape based on various suggestions, but my first light was disappointing. It looked like the flame just curled down the one side, and then turned 90 degrees to head straight out the front and back. I added some extra kaowool and satenite to the side the flame hits to make that more of an oval, and to create a curved transition onto my forge-floor. That seemed to give me a good swirling effect that you can pickup in the videos above.

Here is a video before I made that modification:

https://www.youtube.com/watch?v=YiG8nSvtxmo

Some additional notes I did not include in my original message to Mikey:

• The forge interior is approx 4.75" wide by 3" tall, with the forge floor being 10" in length. I made the forge ceiling insulation extend forward thinking it would act as a hood to protect the metal enclosure. The longest part of the insulation is approx 12" long.
• The insulation is 1" thick 2600F kaowool as the inside layer, and 1" thick 2300F for the outside layer.
• The floor is coated with bubble alumina, the top is satenite.
• The floor is two pieces of 4.5"x4.5"x1/4" high-alumina kiln tile. That was the best fit that the pottery store sold. The fact that they are two pieces is a problem - I was reluctant to try cutting a larger piece since I didn't know if that would be harder than I anticipated. I'll have to do something about this.

Advice and feedback is apprecaited. Thanks in advance.

[Frosty]

The auto exposure on digital cameras can make it hard to judge what temp a yellow glowy thing really is. I'm starting to get used to judging orange. The flame still looks a little rich to me but not bad at all. A pic of the opening cross ways  so I can see what the dragon's breath looks like helps a lot but not essential.

Filling the gap between the floor and wall was a good move, even just pushing it against the wall would've helped a lot. The flame looked to have a good circulation you can see the bright center of the hot spot leading right down the wall and across the floor. Looks good.

I haven't tried it myself but I understand you can score and snap kiln shelf like cutting glass or tiles.

The cone shape you made in the burner port is in the, "Can't hurt, might help," category. I haven't had much if any success making conical "flare" shapes in forge liners and just gave it up. That being said I didn't try very hard soooo. . .

I can't really see anything to gig, sure getting the burner tune a little tighter wouldn't hurt and I'd try for a smoother curve on the next forge but that's about it. I don't think any are very significant.

Frosty The Lucky.

[Mikey98118]

Okay, before I'll write another helpful word on this subject,  Andy must instantly (or at least rapidly) divulge the name and location of his pottery store.

Several months have past since the previous practical source for 1/4" thick high alumina tile, which was (sadly) taken for granted, closed down: just in time for the tile to be wanted. Noncompliance will result in an eventual issuance of a note regarding the safe return of his first born and "and his little dog too"

The Shadow

P.S. If that doesn't work, I will teach the kid to swear like a really naughty parrot, and the dog to pee in the family car; don't try my patience, or I will give the kid crayons and a water pistol before returning her/him!!!

[Andy98]

45 minutes ago, Mikey98118 said:

I will teach the kid to swear like a really naughty parrot, and the dog to pee in the family car; don't try my patience, or I will give the kid crayons and a water pistol before returning her/him!!!

There is a coffeeshop near me that has a sign up: "Unsupervised children will be given a shot of espresso and a puppy"

...Hopefully squeaking in under 1hr is considered rapid enough. The pottery supply I used is called "The Pottery Supply House" (creatively enough). I'm not sure how helpful that will be, since they are up here in Canada - but they do accept online orders, and they do have a rather extensive inventory (including all kinds of alumina tile, 1/4" and 1/2"). 

Here is the alumina kiln tile link: http://www.psh.ca/index.php?cat_id=211

Prices will be in CDN, so remeber to factor in a 20% discount due to exchange rate.

I did read some article somewhere about making your own alumina kiln tile with alumina and veegum (?). Just mentioning in case that is interesting.

[Mikey98118]

"Unsupervised children will be given a shot of espresso and a puppy" Dang; and I thought I was wicked! Suddenly, it is good to be childless.

Thanks for the info; all of it. Now, I think it is time to get back to your forge. Funnily enough I suspect that refining burner performance any further will require Finnish coating and a front baffle plate or brick wall, and an adjustable secondary air choke on the burner port itself, in order to raise internal temperatures high enough to better judge flame performance. Sounds backward, doesn't it? But the thing is that a fair evaluation from photos or video is simpler to do after the forge becomes a radiant oven; also, once the forge climes into the higher heat ranges you my decide that you already have the performance you want, without need of refining the burner Further.

The burner is only part of the forge; if everything revolved only around the burner's performance, most of what we've learned to do when constructing a forge would be "gilding the lily."

Clear back when I was still writing the book, I raised the temperatures in my forge from light orange to lemon yellow, merely by refining the high-emissive coating it was painted in from the stuff that came out of the jar to colloidal grade particles. A few weeks later lemon yellow jumped up to yellow white by stopping secondary air from entering the burner port; this has been further refined by the addition of a variable secondary air choke on the burner port.

It has been stated that good burner performance requires a delicate dance of several factors; ditto for the burner and the equipment it heats.

 

[Andy98]

On 9/17/2016 at 2:58 AM, Mikey98118 said:

will require Finnish coating and a front baffle plate or brick wall, and an adjustable secondary air choke on the burner port itself

...ok, so I didn't understand most (possibly any) of that...

I believe you are suggesting I add an IR coating (ITC or similar), block up the front (what would a baffle look like? I mean, I know what a baffle is I just don't know what one at the front of a forge looks like...) and presumably block up the back (should I just seal up the back completely, minus a small passthrough door? I only really left it fully open because I was worried about backpressure.) 

Note that my "hood" idea (where the arch insulation extends 1" in front of the forge) also means it's hard to actually block the the openings up with bricks (it just forces all the hot gasses downward). Should I ditch the hoods (trim them back to make everything flush?)

Note that I've now run the forge for approx 15 hours, and it seems to be doing fine getting (mild) steel to forging temperatures (admittedly, I'm not sure I'm forging at the right temperatures). To my eye, in sunlight, the steel definitely gets to orange and some lemon-yellow, but I don't think I get light-yellow or white hot. I would like to attempt forge welding in this forge at some point, but I feel like I'm a fair bit away from that?

Here is another video of the forge running. It was fully at temperature (probably had been running for over an hour) and I choked it back a lot (was really trying to make sure the environment was rich as an experiment: https://youtu.be/S1Oz7a3IcOE

Also, separate from the choking, I do feel like something weird happened to the forge after a few multi-hour runs - suddenly the dragon's breath became really orange even when I had the chokes removed. I was also getting near the bottom of my tank (although still reading several hundred psi on the tank side of the guage), and I had just put some borax into the forge in an attempt to weld something. It just seemed different all of a sudden...

Finally, you can see that the T-burner is slumping downwards. I believe the conduit mount is getting hot enough to flex a bit...

On 9/14/2016 at 7:47 PM, Frosty said:

The cone shape you made in the burner port is in the, "Can't hurt, might help," 

...exactly what I was thinking when I did it  - I had grander dreams for it, but they didn't materialize.

I'm confused as to whether I even need the flare. Now that I have a forge running, I have a better shot at making one. Should I bother?

On 9/14/2016 at 7:47 PM, Frosty said:

I can't really see anything to gig, sure getting the burner tune a little tighter wouldn't hurt and I'd try for a smoother curve on the next forge

Yes, I really see now that more oval would really have helped. As far as the the burner tune - do you see it as being too rich? I haven't cut back this mig tip at all (it was waaay too lean originally as far as I could tell, so I overcorrected...)

[Frosty]

Mike is saying your forge is working well enough only minor improvements can be made. Closing up the openings a little isn't quite the same thing as what he's referring to as baffles. The baffle isn't to close up the openings it's there to absorb heat and reflect it back into the forge as IR. I'm sure you noticed what it felt like standing in front of the opening even at a couple yards distance. Yes? All that radiant energy is being beamed out into space like a BRIGHT IR flood light.

The sudden orange dragon's breath happened right after you did WHAT? Think about it, I'll tell you what happened in a bit. Yes, this is a quiz to help develop your observational skills regarding cause ad effect. Cause and effect is what blacksmithing is about, paying attention and learning the language of the: equipment, tools and steel is living the dream.

See above re. the burner sagging in operation.

Uh HUH, do I detect another convert to the "don't need no steenkeen burner flare" club? Flare or not, your choice but take notes. See above.

You had plenty of heat to weld. Did you see any erosion to the liner from the flux you put in? Start with a simple lap weld. Use say 1/4" x 1" strip stock, file, sad or whatever the joint surfaces shiny clean. Dust them LIGHTLY with flux and wire them together. the "billet" in the HOT forge and bring it to the same color as the liner. Bring it to the anvil (If it's sparking it's too hot, less next hot time!) and set the weld. slow heavy "dead" blows. You want solid blows that don't bounce, a lightish blow with a heavy hammer is better than a hard blow with a light hammer. Brush the edges of the weld, flux the edges a little heavier than you did the joint surfaces and return it to the fire. Bring it to the same color as the forge liner bring it to the anvil and deliver a FEW setting blows. Brush, flux and repeat.

The weld should be ready to forge on edge and shape as you like. However seeing as this is a learning experience forge it on edge a bit, say taper it some then pull the handle ends of the strip stock apart and turn it into a heart. You're trying to peal the weld apart.

I'll read your response and get back to you about the dragon's breath.

Frosty The Lucky.

 

 

[Andy98]

On 9/25/2016 at 10:24 PM, Frosty said:

The sudden orange dragon's breath happened right after you did WHAT?

I'm pretty sure I'm going to flunk this test.

Unfortunately, I'm not confident that I am remember the details of what I did accurately. I do believe I remember what I thought at the time,and those thoughts were:

• "The dragon's breath suddenly seems more orange, and at a lower velocity"
• "Is it suddenly running more rich? I don't think I have done anything that would have caused this."
• "I wonder if there is a fuel flow problem?"
• "I wonder if this is related to high temperatures?"

I do believe that approx 15 minutes earlier I had increased the propane pressure substantially and that is why I suspected a fuel flow issue (icing due to higher flow) or a temperature phenomena. It did not make sense to me that higher fuel pressure and temperatures would lower the intensity of the dragon's breath, and I didn't see any ice forming on the tank (admittedly I did not inspect it thoroughly, I just glanced at it and looked at the tank-side pressure gauge which was reading ~500 psi).

When I say that the dragon's breath "suddenly" changed I mean that I had just removed something from the forge, worked on it, then turned back to the forge and noticed it was different. It's possible it was slowly changing all along and I just noticed it at that moment - again, I'm not 100% confident (or even 50% confident) in my observations.

I'm not 100% sure whether this happened before or after I tried my weld, honestly, but I am pretty sure it was before.

If I were to take a guess, I would guess that it was either due to the forge interior being at a higher temperature than I had operated it at before (I do not understand this causality) or there was a flow issue (either in fuel flow, or the burner had gotten obstructed because it slumped). As I said above, I did do a cursory inspection and had dismissed these two concerns at the time but that doesn't mean I got it right.

Honestly, when all this happened I wasn't in an experimental mode so I really wasn't paying attention. I will start keeping a log at all times now.

I did not notice any damage or erosion to the forge liner. I didn't see anything splatter while it was in the forge, and I was really careful to get the fluxed part of the work piece right on the kiln tile. I used very, very, little flux. The whole attempt was unplanned - I had made a mistake and saw the forge-weld as the only option to remedy it so I decided to wing it.

I'm looking forward to making a more organized attempt per your instructions - that likely won't be for a few weeks (late Oct) as I don't believe I will have another opportunity before then.

On 9/25/2016 at 10:24 PM, Frosty said:

You had plenty of heat to weld

Can you tell me how you draw this conclusion? I'm not questioning the conclusion itself, I'm trying to better understand what I should be looking for so that when I do try again I won't fret over temperature. Note that I've never seen any of the metal I'm working with actually spark from heat.

 

On 9/25/2016 at 10:24 PM, Frosty said:

The baffle isn't to close up the openings it's there to absorb heat and reflect it back into the forge as IR

Ah - ok, got it. That makes sense.

 

[Mikey98118]

"The baffle isn't to close up the openings it's there to absorb heat and reflect it back into the forge as IR"

Mostly right, but the baffle does also change opening size; just not as obviously as by adjusting height or width, but by being moved nearer or farther away from the opening edge. This allows very tight openings around the stock for maximum savings of radiant heat, will providing for adjustment of exhaust flow for peak burner performance. This arrangement  also directs both sources of discomfort (radiant energy and exhaust gas) away from the operator more effectively then any other method I know. 

[Frosty]

In the post I replied to you said what you did just before the dragon's breath turned orange, I'll bet it was more of a yellowish orange, not quite a sodium flame yellow. The color of borax in a HOT forge. The color change was the flux and a pretty solid sign the forge was hot enough to weld.

In all probability if you can't get welds to set it's your technique not the forge and that's just a matter of climbing the learning curve.

This little game is more to illustrate the importance of keeping track of what you do and what happens. More importantly especially when doing new things is changing only one thing at a time. In this instance you were only doing one thing but welding changes the forge atmosphere in a couple ways. Mostly though it's the borax doing what borax is supposed to do.

You saw the effect and came to a wrong conclusion. The cue was the conclusion didn't make sense, you didn't do anything that should've changed the air fuel ratio. With NA burners increasing the propane psig will increase the air induction so they lean out. Not a lot, the curve is usually nearly flat but there is a curve.

It's just detective work and a very handy skill.

If I irritate you with test questions or what seems mean games just say so. I get carried away sometimes and don't realize it till later.

Frosty The Lucky.

[Andy98]

2 hours ago, Frosty said:

If I irritate you with test questions or what seems mean games just say so. I get carried away sometimes and don't realize it till later.

Ok thanks. I don't feel irritated. My principle concern is not wasting your or Mikey's time.

[Andy98]

I thought I'd update my progress in this thread for posterity's sake - it's based on advice given to me on another thread (here)

I went ahead and modified the forge. I cut back the forge "hood" to make it possible to block up the front and back with firebrick, see here:

The forge interior now seems quite cozy:

That's it running with the 1/2" T burner at approx 6psi, ambient temperature was around 10C. That piece shows a joint that was about to be successfully forge welded.

With the regulator down at around 1-2 psi, it was still easily hot enough to forge, but not forge-weld.