forge blow out help!!

[CoyoteGear]

I picked up this forge and fired it up this morning and all was having a blast poundin out some fire starters and when I looked into it I saw spoke of the refractory hanging down. I shut off the burner and it looks like the ITC cracked and the kaowool blew out?

This was a used forge but appeared to be in good order when I picked it up.

Did I have the burner to far back and it blew into the seem of the refractory?

Any help would be appreciated. Thanks!

It's a 1/4" steel case, 13" diameter x 18" long. 3" castable refractory, 1" kawool, itc100 coating. With 1" fire brick floor. Single venturi burner. Was operating at 5# fire the hour or so I used it. 

Here's a pic of the burner flame when I first starred it.

[Frosty]

Yeah it wasn't supposed to do that. The construction details don't make sense. Forget how thick the shell is, it really isn't important so long as it contains the stuff you don't want drifting around the shop. Stove pipe is plenty strong enough to support work weighing more than 100lbs.

3" of castable refractory? and only 1" of ceramic wool? Having that little blanket is completely unnecessary as an insulator after heating that much hard refractory. On the other hand if the blanket is INSIDE the hard refractory then both are exceedingly poorly used.

By the looks the blanket is the inner liner so yes having your burner too far out super heated the blanket and maybe blew flame into it and melted the blanket then blew it away from the hard refractory. ITC-100 can't protect it from this kind of action.

What you need for a liner that has both good efficiency and a good lifespan is 1/2"-3/4" hard inner liner surrounded by 2" of refractory blanket. Kiln wash the inside surface with 1/4"-1/2" IR reflective like ITC-100 and you have a liner that will do well and last.

The flame looks to be well tuned without choking at all, this is a GOOD sign. I wonder if the fellow who built the forge bought the burner, I don't think he understood how forges work.

Frosty The Lucky.

[CoyoteGear]

He did not buy the burner, it is made from an online instruction, with a 35 mig tip. and 1" Black pipe.
I'm pretty bummed that this happened on the first day after getting it home.

This is my first built forge, I tried to set it up the same as i was instructed, with the burner tip about 1" back from the inner wall, and centered in the little cutout area from the insulation. I'm not 100% on the dimensions of the refractory that was just from what I could measure, and guess off math.

Yes the kaowool is on the inside, with the castable on the outside.
Can I patch this and use it? I have a very small amount of ITC powder (about 2 tablespoons) left. And some kaowool. Do I just replace what is missing and then to a layer of ITC?

[Frosty]

I'd build a different forge. Putting the hard hard refractory outside the Kaowool is a complete waste of castable refractory. You need the insulation (Kaowool) on the outside to keep the heat in the forge. The hard refractory is to protect the Kaowool from the fire, mechanical damage (getting poked and ripped by steel) and flux.

As it's built it will just destroy any Kaowool you repair it with.

What is the forge's volume? A 1" burner is a LOT of heat and that's a mighty good looking flame for a 0.035" jet in a 1" burner. When you say 1" are you referring to the burner tube, the part that penetrates the forge wall or the air intake port on the T? From the picture it sure doesn't look like a 1" burner to me but I can certainly be wrong eyeballing a picture.

I'm afraid you're probably going to need to rebuild that forge from the shell in to get it right. Buck up though you don't live far from Seattle Ceramics Supply. You can buy castable refractories, Kaowool and zirconium silicate for reasonable prices. You can make your own home brew version of ITC-100 using Zircopax and either Kaolin clay or by sifting the fines from a water curing castable refractory.

I've been playing with a water curing castable name of "Greencast 94". It's a high alumina 3,000f castable refractory and by sifting the sand and little bits out it leaves the cement element which I've been mixing with the Zircopax to make a high temperature, IR reflecting kiln wash and inner shell. I'm not finished testing it in my forges but so far it's holding up very well.

I can't afford ITC-100 so I've been experimenting with a home brew replacement. A 1lb can of ITC-100 was in excess of $125.00 last time I checked PLUS S&H. We (the club) bought Zircopax and shipping included it ran around $3.76 per lb. and we didn't have to pay for the water ITC-100 includes in the can.

There have been a couple good threads regarding building and lining forges recently I highly recommend you read through the a couple times to get an idea what you're going to need to do and what your options are. Again I would NOT repair that forge it's put together wrong and what happened will happen again.

Frosty The Lucky.

 

[CoyoteGear]

1" going into the forge, the T opening is 1 1/4". That's disheartening news to tear it down. I had an old propane cylinder I was turning into a forge and bought this to save time, now in right back to where I was before.

Internal volume is 508 in3...

It was bigger than I wanted but I got excited, and thought I could score a sweet deal on a forge.

Oh well, I already have a bunch of kaowool from my propane tank forge. I might just finish it and put this one in the back of the shop with the other costly lessons I've had learn.

Thank you for the input, I'll get over to the forum and read up.

[ThomasPowers]

I've begun to see more and more "I built it off a design on the internet/youtube" stuff showing up---sometimes by folks trying to sell them as a business; but they have not clue if it is a good design or not.  When they tell me the person posting it told them it was a great design I ask them to hold on a moment while I put up a web page that mentions that giving me all their money, tools, house and car is a really really GREAT idea.

When things were mainly in books you tended to get a filtering as a publisher didn't want to risk tens of thousands of dollars on stuff being written by people who had no clue---and even then some real bogus ones slipped through.  Now when the cost of posting is trivial we get a LOT of clueless people spreading their cluelessness AND people who don't accept the value of experience, education, etc---one person's viewpoint is just as valid as another. (I suggest that if they even need open heart surgery they have the janitor do it as his view is just as good as the surgeons and he will be *much* cheaper!)

[jcornell]

were I in your shoes, I'd get some cast-o-lite 3000 and some superwool and kaolin and zircopax and a bottle of fumed silica.

I'd take the front and back of the forge off and rip out the castable and the kaowool (this step will require gloves and a respirator.)

I'd then reline the steel shell with superwool HT (my favorite insulating fiber).

I'd mix up fumed silica and water (about a cup per gallon) to use as rigidizer for the superwool.  Once it was decently dry, I'd put the burner in and cook the fiber to drive all the steam out.

Then I'd use the cast a cast-o-lite 3000 to make a hot-face shell inside on top of the now rigidized superwool.  You're shooting for 3/8" to 1/2" thick face on top of your superwool.

Once this is dry, I'd put the burner back in again and cook the refractory.

Then I'd wash the inside of the now cooked refractory with a mixture of zircopax & kaolin (4:1).  Let this dry, fire up again to cook the reflective coat.

After that I'd reinstall the bricks in front and back and start forging.

 

 

The fundamental problem of the design you've shown is is that the kaowool is protecting the cast refractory, which is backwards.  It's like swapping out a 30 amp fuse for a 20 amp fuse - now the wiring of your house is protecting your 30 amp fuse from blowing.

[orange]

I'm kinda confused. I am having a hard time picturing the kaowool and refractory placement. I made a little picture to show how I think you said it was set up. Is this how your forge is set up and is this the proper way? I guess I'm more of a visual person so please allow me this clarification.

Adam

[CoyoteGear]

No, this forge was set up the opposite. The cement is one the outside, then a thin layer of kaowool.

I've put this forge on the back burner and continued on with the one I was building before this one.

It's an old propane tank, burners are from high-temp tools, I cut and measured the kaowool last night. And no worries it'll be done correctly

I'm doing 2 inches of kaowool then a layer of castolite 3000. With a floor made up of k28 kiln bricks, and the front and back door will also be kiln bricks.

I was almost done with it when I saw this forge pop up for sale and got greedy. Thinking I could finish my propane tank forge AND buy this one, added to my current farriers forge giving me 3 forges of different sizes.

One day I will finish this big one, I'm only in it $100 and I got a burner, regulator, 2x pressure gages, and a bucket full of fire brick, plus the cart is on (even tho its pretty cheaply made) and the 13x18" steel pipe body. Not too bad,  just not what I was hoping for.

Thank you guys for all the help. I appreciate it.

[Frosty]

Coyote Gear, how about attending the next NWBA meeting and get a look at proper forges? I don't think you have to join to attend a meeting.

Adam. Your drawing is the correct configuration except for the refractory thicknesses. Thick insulating layer on the outside and thin hard high temp IR reflective layer for the fire contact layer on the inside.

The shell doesn't need to be pipe heavier than stove pipe. It's only real job is to contain fibers you don't want to breath and supply hardware mounts for legs, doors, burners, cup holder, etc. Other wise your drawing is a decent chamber configuration. If you make it a vaulted chamber (mailbox shape) and you level the burner angle out so it's striking closer to the top at a tangent you'll have THE design.

Mike recommends high alumina kiln shelf for the floor and I'm in his camp on this one. Forge liners are wear items, propane is a very chemically active fuel and will erode the liner. It's pretty easy to wet down and re-wash the hard refractory vault with a kiln wash. The floors tend to take a real beating so using something that's easy to replace while being above of average resistance to the fire and flux is a win win.

Frosty The Lucky.

[Rashelle]

A membership is required to attend the monthly events for the NWBA. Due to insurance. On the plus side there is a quarterly membership that's $15.00 as opposed to the yearly membership. Members pay $10.00 for the monthly event. Normally that is a 3 hour demo from a paid demonstrator followed by open forge. We occasionally have workshops and just flat out open forge days. Next one is April 23rd. Demo will be by Berkley Tack, in place of Tim Gabriel as Tim is having eye surgery. Berkley always does a good demo. So needless to say the small fee's do NOT cover the cost of the events. These are provided to promote outreach and education.

[Frosty]

Where is the next meeting located Rashelle? The coyote is in Bremerton. Do you guys have a permanent location?  IIRC you demo and or teach at Ft. Vancouver?

Frosty The Lucky.

[Rashelle]

The NWBA has a permanent location at the Longview Fairgrounds.

I demo and sometimes help teach other volunteers at Fort Vancouver. There is some overlap amongst NWBA and Fort personnel. I work at and teach at Trackers PDX. I'm still the board member in charge of the NWBA's monthly events, somehow, lol.

[Frosty]

Of course you're still a board member you haven't died yet. I didn't ask to be president of the Alaska club and they voted me pres for life while I was in a coma after the tree attack. A club has to have an elected board and nobody want's the job so once you're in you're in for good. Sort of like the Mafia without the concrete overshoes. . . Hopefully!

Next time we're in the PAC NW I'll shoot you a note, I'd love to meet face to face.

Frosty The Lucky.

[Rashelle]

I'll look forward to it Frosty.

Coyote do try to get to one of the Mentoring center events. Lots of learning opportunities, even though it's a drive. The yearly conference is in May so there is a 3 day event coming up. Should be worth the drive, lol.