Forges 101

[Mikey98118]

I thought that silicon bronze castings would go grate with wrought iron gates.

[D.Rotblatt]

9 hours ago, Mikey98118 said:

I thought that silicon bronze castings would go "grate" with wrought iron gates.

 

[ThomasPowers]

They certainly make for neat spider web accents.

[Mikey98118]

Huh?

[ThomasPowers]

You never seen spider web brass brackets in the corners of gates before?   I have and thought they were neat enough to remember. (Now if I could just remember where...)

[Mikey98118]

I closed shop and left Southern Cal. just a few years before metal arts came into fashion, and moved to a Seattle that had little clue about it. There was good iron work here, but it was a century out of date. Art was replaced by making a living and being a husband; no regrets.

[Frosty]

Excellent write up Dan, I even see proper drafting symbology!

Frosty The Lucky.

[D.Rotblatt]

On 3/23/2019 at 9:32 PM, u_p_country said:

wait for more info from D.Rotblatt

I've ordered a pint of the colloidal silica that looks good.  I'm off camping with my son for the week, I should have it when I get home.  I should have results within a couple of weeks.

[D.Rotblatt]

1 hour ago, Frosty said:

Excellent write up Dan, I even see proper drafting symbology!

Thanks Frosty!  One semester of Architectural detailing and looking at a lot of plans.  

[Frosty]

2 hours ago, D.Rotblatt said:

Thanks Frosty!  One semester of Architectural detailing and looking at a lot of plans.  

Dad insisted I know how to read and draw blue prints, started me out around 12 or so at his table. I HAD to take drafting any time it was offered so I took drafting every single semester jr through senior high and one in college. 15 drafting classes counting summer school. I was a professional draftsman for less than a year, then CADD hit the scene but I was working in the field as a driller's helper. Ever notice how elaborate the compass rose was on old school prints? It was the only way to sign your drawings, blue prints are no place for individual expression. Just the facts maam. 

Getting it right really stands out to me. 

Frosty The Lucky.

[u_p_country]

13 hours ago, D.Rotblatt said:

  I should have results within a couple of weeks.

Have fun camping!  It was 9 degrees F this morning and we still have lots of snow so camping wasn't even on my radar.  I suppose there are lots of places in our fine country that are having warm spring weather!  I'll look forward to your results.   Thanks again for sharing your experiences so we can all learn!

[ThomasPowers]

It was 79 degF when I got off work yesterday; but we expect we will get some warm spring weather sometime....I've been sweating a bit lately while hand hack sawing an old wagon tyre---3" wide x 1/2" thick, got 6 pieces cut right now.  It's interesting but you can really tell that the outer face of the tyre was work hardened from use.

[Soopafeen]

Hello, I have been tinkering with my forge for sometime now and just finished a 3/4" high speed Mikey burner (pictures in Burner 101) but I have noticed my heat doesn't quite seem to be high as it should be, I lack proper exhausting of gases which I know hurts me so I plan to purchase some K26 or K28 bricks so I can make a moving wall.

My current forge is 12" long x 6" wide x 3" tall including 1" walls and ceiling with 2" corner supports and floor 8# kaowool ridigized with kaolin since I ran out of Zircopax I mixed it with some Calcine kaolin and some grog. It works but cracked quite a bit.

Plan on picking up some more Zirconium Silicate as well open to trying other recipes if recommended.

I feel that my forge isn't hitting temps that it should be below are pictures of a burn test with the openings closed as much as I could for the time being. If I were to guess it hit ~2300F.

First picture 10# burn.

Second picture 20# burn.

Third picture 20# with 3/8" x 1-3/8" 1018 bar inside.

Forth picture bar after 3 minute soak.

Fifth picture just shut off burner.

Thanks, Corey

[Mikey98118]

Well, we need to begin with the burner size.

.. I thought you built a 3/8" burner, which would mean that your opening remark is a typo. Or, I'm wrong and you really did mean to say that it is a 3/4"  size burner in the forge. The difference is that a 3/8" size burner in this size forge is doing a heck of a good job to get it this hot, but you can't expect anything more out of the burner. You will have to get any more benefits from forge improvements.

On the other hand, if you really do have a 3/4" burner in that  forge, maybe it isn't doing all that well, and you need to get more out of the burner after all. Maybe the burner is running lean? So, lets start with which size is correct; 3/8" or 3/4"?

 

[Soopafeen]

Mikey: No typo 3/4". A little confused though in our private messages you said the burner looks to be burning well but I will mess with the airflow a bit to see if she is running a little lean.

Burner only had about 1/2" of the air slots open.

Hypothetically speaking couldn't we just shorten the air slots to say 1.5" long on Mikey burners if properly rectangular and perhaps take 1" off the mixing tube to compensate? It seems unnecessary to have massive 3" air slots like my burner has if I only use at most 1" of the slots.

[Soopafeen]

Did a test burn this evening before nightfall and lone behold my burner was running quite lean to my surprise I under estimated the efficiency of my Mikey burner there was definitely a more even heat.

Also noticed considerable difference in scale which leads me to believe I can back off the airflow a bit more.

For adding glass bubbles to refractory would something like microspheres advertised to be added to resin epoxy work?

Picture #1: Airflow adjustment difference.(Don't mind my goats in the background)

Picture #2: 20# Burner flame while cold.

Picture #3: Temperature after 10 minute soak.

 

 

[Mikey98118]

6 hours ago, Soopafeen said:

1.5" long on Mikey burners if properly rectangular and perhaps take 1" off the mixing tube to compensate?

Yes. When I wrote the book I was going for overkill. Also, though I never admitted it,  all the original burners were built to work at up to 60 PSI gas pressure air out in the open air; that takes more air. I wanted to be sure the design was STABLE. Safety first you know. Twenty years later, smoothing out a design that I know is stable makes more sense

[Soopafeen]

I did not think of that, a stable is flame at 60PSI in open air is quite impressive, well done Mikey.

Also you are smart to smoothing things out after it was proven to be stable in some what unrealistic circumstances.

[D.Rotblatt]

On 3/26/2019 at 5:25 AM, u_p_country said:

It was 9 degrees F this morning and we still have lots of snow

I’m in Death Valley. 80’s in the day, 60’s at night. They close the park in April due to heat. 

Now, to make this appropriate for iForge: at the borax works from 1880’s, the wagon from the original 20 mile team company. The wheels are 7’ high, about 8” wide...If original I bet the tires are wrought iron. I could see the smiths hammer marks on the side of some. So we have both flux and blacksmithing. 

 

[u_p_country]

Wow! Those pictures sure tell a story!  60's would be nice for a change here!  We were shouting for joy that we topped out at 48F yesterday afternoon!

[Frosty]

I was too young to remember much last time I was in Death Valley, Dad was a rockhound and the club was collecting crystals. 

The snow's almost gone here, it even reached 53 f. on our porch a few days ago, highs in mid  to high 40s. SWEET but I'm not counting any hatchlings, I've seen serious snow and sub zero temps this time of year. Mid to late April I'll start thinking new season.

Frosty The Lucky. 

[Irondragon Forge ClayWorks]

Just the thought of shrinking those tires onto the 7 foot rims gives me the shivers.

[Frosty]

The larger the diameter the easier. You don't need an inch more dia. to slip a tire on and the circumference of a 7' dia tire is better than 21'. How much temp increase do you need to get another 1.5" out of 21'?  Two flakes of straw spread around the tire and a cup of kerosene so it lit evenly should be plenty to bring it up a couple few hundred degrees.

At least you wouldn't have to worry about the wheel being dry enough. 

Frosty The Lucky.

[Mikey98118]

Place joints at opposite points

Box forges don’t necessarily need a solid shell; steel angle and thread stock will do just fine with brick in their construction. Many people prefer sheet metal; in that case, it is important to remember not to attempt welding them completely. You need to have some movable parts in every direction, by placing joints at opposite points, to keep the form from being distorted during thermal cycling.

[Mikey98118]

Burner sizes:

(1)  Any 3/8'' size burner, which can make a neutral flame, should be able to heat 130 cubic inches of forge interior to welding temperature.

(2)  () A 1/2”  burner should heat a 175 cubic inch interior that far.

(3)  A 3/4” burner should heat a 350 cubic inch interior enough.

(4)  A 1” size burner should do for 700 cubic inches; and a 1-1/4” size burner should handle 1000 cubic inches.

These figures assume that the forge has two inches of ceramic fiber insulation, and a proper exhaust opening (either the right size for the burner, or employing a baffle wall).

    Burners that can combust completely in a single neutral flame envelope can handle larger interiors. Most tunnel, oval, and “D” shaped forges tend to be longer than their widths, and will benefit from two smaller burners, rather than one larger burner. Re-emissive (heat reflection) coating of all hot-faces, and adjustable control of secondary air through the burner portal will also increase the amount of forge interior a burner can handle.