Forges 101

[Frosty]

I mixed 2pts. Zircopax to 1pt. Cast-O-Lite 30. I added enough water to make a consistency about like latex paint and painted it on with a brush. Making it that thin means you have to mix it almost constantly or the zircopax settles out.

The ONLY thing I have to add to Mike's above post is about buttering. If you don't wet the surface before spraying the rigidizer it will dry on contacting the dry material. Capillary action can ONLY happen if it's wet enough to flow.

Interestingly enough the colloidal silica rigidizer is denser than water so as it flows through capillarity it will push the water ahead of it by displacement. It doesn't do this forever but it does allow the rigidizer to penetrate farther.

Buttering a hard surface is even more important as the rigidizer, mortar, etc. will NOT penetrate a hard surface it flash dries on the surface unless it's way too wet a mix. You want the rigidizer to penetrate the surface so it bonds properly.

Buttering is an IMPORTANT part of the process of getting stuff like a hard refractory flame face to bond solidly to a refractory blanket insulating liner. Getting the blanket to bond to the shell. and getting the kiln wash to bond to the flame face.

Heck, anybody out there throw pottery? What do you do when you stick the handle on a coffee mug? You wet the joint surface right? It's not quite as important on freshly thrown pottery as it is on masonry but it ensures a good bond none the less.

Butter it up!

Frosty The Lucky.

[Mberghorn]

As Paula Dean would say, "you can never have too much butter!" Thanks again, you two, for clearing up my confusion.

[Mikey98118]

I've never wet the wool first. On the other hand, Frosty's view point is well reasoned out; I well butter from now on

After all, why do some thinging well enough, when you can do it even better

 

that would be something; definitely something...

[Mikey98118]

Why bother about safety regulations?

I harp on safety quite a bit. On the one hand, because of the proliferation of regulations in western countries, and the various government bureaus enforcing them (who seem determined to outlaw everything they can), it is tempting to say " since I can't do right, I will just do what I please."

Back in 1986 I was running an ornamental iron business out of my my garage, and burned it halfway to the ground. First the fire department came, and a couple of days later my insurance adjuster paid a visit (without my even making a claim). He asked what happened, and I came clean; result; half what the company would have paid otherwise, and no fine from the city for what I was doing illegally in there; it could have been a big fine and no insurance pay out. I've built more ornamental iron in that building over the years, but never again for money. I also installed fire extinguishers, kept a charged water hose ready, and never allowed anything to be heating without my being present, etc., etc.

A few months after my burner book was published in 2004, I was standing in line at Safeway with several firemen, and one of them turned to me and asked if my name was Michail Porter. I acknowledged that it was. He said he'd seen my book, with a knowing grin. My photo doesn't appear on or in it; they had been keeping track of me all that time.

What I'm getting at is that, if the nasty brown stuff ever hits YOUR fan, you won't care about whether or not you could have followed safety regulations perfectly. You will be glad of everything you complied with, and sweat everything you didn't.  Also, just because your local Fire Marshal hasn't payed you a visit, doesn't mean the powers that be don't know what you are doing.

Bottom line? Just because you can't do everything right is no reason for doing nothing at all.

[Frosty]

Truer words were never spoken Mike. The FD doesn't spy on folks but they're all very much into fire and will remember what caused one, especially if it's something new. Then you publish a book about the very thing that got away from you. Of course they noticed. 

Risk management is important, the riskier our endeavors the more important we be careful. Being careful bad things don't happen is only one risk we run. Another is operating a home built propane burning appliance. What insurance company wants to cover that one cheap if at all? 

A thing to remember when dealing with inspectors, they are bureaucrats and if presented with something they don't understand the safe response is to say NO! There is good logical reasons this is actually a good thing or your neighbor's teen age kids would be building liquid fuel rockets or worse. I would've.

I deal with risk by having a steel shop more than 100' from the house, forest cleared back more than 50' at it's closest. Everything inside is paid for and mostly fire proof. If something goes bad there isn't a lot of fuel and not too much to be damaged. I'd really hate to have to replace the electric motors and my welders but maybe our home owners would cut me some slack. It's not a professional operation so maybe.

Frosty The Lucky.

[Mikey98118]

The funny part is that the only hot work I did in the garage at the time, and for many years afterward, was wire-feed welding. It was a weld berry landing just right on the wooden wall that caught fire, while I was in the house eating lunch, but yes, I can only imagine what the fire department might have thought about my playing around with propane burners, forges, and casting furnaces later on. Ironically, I haven't Played with anything hotter than a hand grinder in there in decades. I test new burners and equipment in the back yard, and studiously avoid welding on them, so that the people I write for do not need to own a welding machine to follow my instructions; ditto for oxy/fuel torches for the same reason. Heck, since rotary tools became so cheap, my angle grinders are just collecting dust. If the fire department is waiting for more trouble from me, they will have to wait for lighting to strike

[Irondragon Forge ClayWorks]

While building the forge other ideas pop up, like using it outside to prevent fires in the smithy.  Then having to move the propane tank from the other side of the garage and building a cart for the forge from a cannibalized BBQ that someone had dumped on our road. The last several days took up those projects. Had to get a load of crushed limestone to level the land outside the smithy door so we can use the forge outside then step through the door to the anvil's and power hammer. The next project is to replace the chicken house curtains a storm tore up.

 

[Mikey98118]

That does look like a nice area to do casting...

[Mikey98118]

Microspheres as lightweight refractory insulating fillers have the advantage over traditional insulating fillers of toughening, instead of degrading, refractory's overall strength.

The present king of refractory microspheres is bubble alumina; unfortunately it is hideously expensive. There is such a thing as silica-alumina spheres (a lower grade product for less money), but if you can’t buy it by the ton, you’re out of luck. Fortunately, hollow silica microspheres are CHEAP, CHEAP, CHEAP!!! And, silica microspheres can be had in small quantities. Naturally we would all prefer to use alumina microsphers, but second best is better than too expensive to use at all:

 

http://www.pilotshop.com/catalog/cmpages/bubbles.php?utm_source=google&utm_medium=cse&utm_term=01-14600&gclid=CjwKEAjwrMzHBRDW3saA88aT80MSJACbvo1TsEAqmKE6j6dw_HPx_aedQY4QdYk9gvcHc6jQ9TbfdxoCBm7w_wcB

https://www.systemthree.com/products/glass-microspheres?utm_medium=cpc&utm_source=googlepla&variant=13268254340&gclid=CjwKEAjwrMzHBRDW3saA88aT80MSJACbvo1TKf-AIBRBrHxTO3Ymqi_-BI-7HJAyFre6P2kFHca9vBoC-OPw_wcB

 

How much can you use? Originally hollow microspheres (AKA mcroballoons) were mixed into plastic to create composites known as syntactic foams; later they were mixed into metal foams, and finally into ceramic foams. Of course, ceramic foam isn’t likely to be very sturdy. Probably the best refractory to microspheres balance will be reached somewhere between 25% and 40% by volume for a nice balance of lower density, higher specific strength, and lower coefficient of thermal expansion (which lowers a refractory’s exposure to cracking from thermal cycling). How strong would the refractory end up? These spheres are used to lighten structural concrete; that tough enough? Let the debate begin…

[WoodnMetalGuy]

On 4/17/2017 at 1:55 AM, Mikey98118 said:

Originally hollow microspheres (AKA mcroballoons) were mixed into plastic to create composites known as syntactic foams;

I've used them in boatbuilding, mixed with epoxy to produce an easily sanded filler, not used for structural purposes.  Hadn't thought about putting them in refractory...  -- Dave

[Mikey98118]

 

I had only intended to to paste the address for this video in this section, cut the video came along, and would not go away. The moderaters can X it at their pleasure. In the meantime, it show one a Diamondback forge from the point of view of a satisfied user; more to the point their is a lottowing video on the site that shows him relining that forge; it's quite instructive.

[Mikey98118]

Dave.

We are all looking for economical ways to improve performance and maintenance life in our equipment. Anytime, I run across a chance to, I like to bring it forward for evaluation. I don't believe in homemade refractories; economically they just don't work out. But a low cost chance to improve the commercial blends is always worth a try. This stuff could end up being as worthwhile as colloidal silica did; if so I would be grinning all over the place.

In the video you can access using the one above the guy mentions a product better than fiberboard. I for one intend to follow that lead...

[Frosty]

Didn't he say something about being in the far east and the refractories he uses being made locally? I don't know if we could try the stuff if we wanted to.

Frosty The Lucky.

 

[Mikey98118]

I don't know either. But a HUGE amount of materials like that are made in the far east and imported here. That's just a fact of life with our "global economy". Irritating, isn't it? On the other hand, most often in the past, such "raw materials" were only available to manufacturing companies, even when they were supposedly made here in the good old USA.

[Frosty]

Yeah, S'true Mike. It's almost enough to make a boy want to make his own refractories. Tried that not going to do it again. It's one thing to muddle around mixing known things and something else again to actually make a useful refractory.

Well, I'll keep my fingers crossed, maybe the product will appear over here somewhere. Has anybody contacted him and asked what the heck it is, maker, etc.?

Frosty The Lucky.

[Mikey98118]

Agreed; adding stuff to commercial refractories can make  sense, but not making them from scratch.

[Mikey98118]

High alumina ceramic boards, maximum service temperature rated to 2822° F  (1550° C) http://www.rath-usa.com/kvr.php

[Mikey98118]

Zircar has several types of ceramic high alumina and zirconia-alumina fiber boards: https://zircarzirconia.com/alumina-zirconia-boards/  and http://www.zircarceramics.com/pages/rigidmaterials/aluminaproducts.htm   

 

Zircar has several types of ceramic high alumina and zirconia-alumina fiber boards: https://zircarzirconia.com/alumina-zirconia-boards/ 

And http://www.zircarceramics.com/pages/rigidmaterials/aluminaproducts.htm   

 

[Mr. B]

Hi everyone, My name is Robert I live in the Interior of Alaska and have long winters that I take up with my knife making hobby and part time business. I mostly did stock removal, but I am more and more interested in pounding my steel in shape rather than cutting and grinding it. With that in mind I have a few queries.

 

(Wish I found you all a week ago).

 

So I built a small propane forge and used two inch insulation with sodium silicate as the rigidizer and had planned to put a coat of IT-100 over that after it's first heating. I was planning on using the fire brick I have for the floor.

After reading this thread my take is the straight (No water) silicate I used was not the best choice, it will degrade with flux, but will be okay for a bit as long I don't do any heavy welding. The Fire Brick for the floor will not work as it sucks up heat instead of reflecting it. So if I got this right, I have a pint of Sodium Silicate left over.  Could I mix it with perlite in a form to make a board for the floor or it just good glue for multi-layered ceramic blankets sticking together?

OR........

Should I just rip it all out and start over?

P.S. The pic has the cement board for the skin, I took that out and put in sheet steel with nuts and a bolt as fasteners before I insulated and I hinged the top tube holder so I could replace the heat tubes without tearing it all apart in the future.

 

any help is appreciated, Gentlemen.

 

[Mikey98118]

High Robert,

If you pinpoint your area a little better, other Alaska smiths can interact with you, who know how to find critical materials more locally than like Seattle. Frosty lives in Alaska and Mikey don't, so you're pretty safe with this.

First of all, congratulations on choosing what looks very much like fireplace backing (cement board). I had decided to go with it for the shell (skin) on a square forge this summer, which I had sworn (to myself) never to build...but they are becoming too interesting to keep on ignoring.

Anyway that leads into one of your questions. Sodium silicate ( water glass) is commonly used to glue Perlite together for tertiary (third) layers in or on heating equipment; it melts at 1900 F, so you want it to definitely be located outside of the Kaowool (ceramic wool blanket) which is use-rated to 2300 F, and does not easily melt under 3000 F. The best use for water glass is to paint the inside and outside surfaces of the cement board, because its major weakness as a construction material, is a tendency to warp after one one side gets wet; just a lot of exposure to damp air can to the deed. Sodium silicate is commonly used as a water resistant coating on driveways to keep oil leaks from ruining the cement's appearance.

You state "... and had planned to put a coat of ITC-100 over that after it's first heating. Wrong on  three counts (oh boy are you busted but good :-)

(1) Regardless of what else you do, rigidize the ceramic blanket first (okay second. coat the cement board first). Soak the blanket clear through, all the way to the forge shell. Silicate based rigidizer is just colloidal silica in plain old tap water. Common feather light (cheap to ship) Fumed silica is colloidal; spritz it on, heat up the forge until it dries out and bonds to the blanket, and your done. Later on your layers of insulation will be firmly standing in place instead of trying to sag out of position; they will also be bonded to the shell and to each other. But most importantly, they will resist shrinkage from exposure to high heat, and do a fine job of supporting the finish layer (hot face coating)acainst damage and spalling away from the pull against it from insulation exposed to heat shrinkage in the in the layer just beside it; this is important protection for any stiff thin coating, and especially with ITC-100

(2) ITC-100 is used for heat refection by re-radiation from coated surfaces; it is not a good choice of finish coating for ceramic blanket--especially not--if the blanket hasn't been rigidized, because it has no mechanical toughness at all, due to phase changes in the zirconium particles

(3) ITC-100 is a vastly overpriced choice, compared to two other heat reflective coatings, wich DO afford mechanical protection for a whole lot less money; they are both sold and shipped in small quantities by Wayne, a member in good standing on this forum, who also has a nice looking dog, and a cowboy hat I covet; it's white, and with the nice dog I could meet girls...oh wait, I'm waaaaay to old for meeting girls, and besides Kathy would skin me alive; he can keep the dog and hat, under the circumstances...

If you already bought the ITC-100 all hope is not lost. Change your choice of finish coating to Satanite or still buy one of Wayne's products, and use the ITC-100 in a double layer over it. For the first layer, simply coat the ITC-1-100 straight out of the jar. Heat it to stabilize it on the forge surface, and then paint on a second coat that you have first separated in some extra water. Here's the deal; the active ingredient in ITC-100 is zirconium oxide. BUT, the amount of re-radiation zirconium gives off depends of the particle size in its coating. Mixed into enough water (a couple of inches in a water glass) the crude particles will separate out of solution, sinking to the floor; the rest is colloidal particles; as in super small, which re-radiates over 90% of the heat that falls on the coating.

It looks like you employed conduit fittings to hold your burners on the forge top? Good move, but your photo doesn't show the burner ends and gas plumbing. Since this thread is supposed to be about burners, how about being a nice guy and giving us a peek at yours? Pretty please?

[Mr. B]

Well I'm not usually this easy, but. ... ;-)

Só the blankets I have now installed can I turn them around and put the sodium silicate side towards the shell? Then regidize with the zi?

[Mikey98118]

"Só the blankets I have now installed can I turn them around and put the sodium silicate side towards the shell? Then regidize with the zi?"

You certainly may, and no harm done. It was the other end of the burners I was looking for, but truthfully that is such a great photo of the burner threads, electrical conduit fittings, and steel plate to anchor it all safely, I can't complain

Steel absorbs heat fast, and then gives it up to materials you don't want overheated, just as fast. Lose the door; your forge is going to need that much exhaust opening to run right anyway.

You can cut the forge opening a little oversized and glue the blanket all around the opening with, with rigidizer, so that the new opening ends up the same size after the blanket is pushed through it). Then use a narrow strip of blanket around the outside of the opening to further protect the cement board from super heated exhaust fumes.  Finish coat the additions to seal them. Yes, you have some extra work to do, but if you had used a steel shell, those exhast fumes would only have made other troubles around its opening; take heart.

If you haven't finished the burners, a can only suggest choosing a Frosty "T" burner in this forge; why? Because the "T" makes a soft flame, which is less likely to impinge on the forge floor, and more likely than a fast hard flame to give up its heat to the forge interior then a fast flame, which needs a circular path to do so efficiently.

[Mikey98118]

Ack; too late! you appear to have a couple of Mikey burners in that forge. Fortunately you installed two of them, which I would normally consider one too many in that space. Which means that you can turn them way down; they will still put out very fast flames, but when turned down, the flames get shorter; you are still okay.

[Mr. B]

Thanks for your help.  I was wondering if that was you I have bought them from. You got them on e-bay, yes? 

Oh for clarification.....I did do away with he cement board. It fried on me when I did a test heat. Pretty much turned to dust. went with sheet steel/nuts/bolts and washers for a skin.

[Mikey98118]

I still plan to try cement board...

No, they are not my burners. As an author and recognized expert on the subject. My selling burners would make any lawyer's mouth water with anticipation; in a tort case, he could scream undo influence. I don't need the grief. Burners given away; many. Amount of burners or other heating equipment sold; zero.