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I Forge Iron

Will this work, asking for a friend.


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I got this idea/design for a forge from YouTube, it was before i found this forum and all its information so i would like to get your opinion. Scrap the idea, or just build it and rework it after i get better at holding a hammer.

It is made from Firebricks, holds a single Devil Forge burner at the top and is clamped together by treaded rod and welded angle iron and flat iron.

The opening is 110x110 mm and 212mm deep.

Capture.JPG.8b907b83ee4e548ffafddbc5b564f5ea.JPG

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Are there hard non-insulating firebricks or soft insulating firebricks?   Will your system have problems with the chimney effect when shut down or tend to rerun exhaust gasses making Carbon Monoxide production spike high?

Have you looked at any of the many peer reviewed forge designs already posted on this site?

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hard non-insulating firebricks, since that is all i can find close to home, and it was what was described in the video. For as far as i know the burner just uses the venturi effect to pull in oxygen. So when i turn down the oxygen the flame should cool down and when i turn of the gas everything should be pretty safe. Is that what you ment?

I have seen many forges here using ceramic wool, but the ones i find in the Netherlands only run to about 1000 C, and the language barrier makes it hard to find what you guys are talking about.

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Hard firebrick that are not insulating WASTE a terrible amount of the heat you are trying to save in the forge to heat your workpiece. As such forges using them tend to run much colder/or use a lot more gas to get them to heat up to working temps.  Over here I call it the: "I'm going to save US$50 in refractory costs and spend $200 extra on fuel costs and expect to save money!" syndrome.

When you turn a forge off heat stored up in the forge will tend to chimney up a vertical burner. This can cause issues with parts that are not so heat tolerant!

The CO issue: hot exhaust gasses *rise* if the burner is sucking in the ambient atmosphere will those gasses get sucked in and re run causing increased CO production and is the ventilation for the forge area good enough that this is not a problem?  (I often run reducing for bladesmithing; I have a 20'x30' forge area with 10' walls, open gables and opposing 10'x10' roll up doors aligned along the common direction of the local breezes. I have not had problems. I know people that have barely escaped killing themselves with CO---as in stumbled out of their shop and fell unconscious into the snow on their patio.

There is a variation of that forge using *good* firebricks and side mount burners that Frosty has posted several times in the gas forge section. See if you can profit from that design!

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I will look that up, thank you sir. Those insulated stones are not even that much more expensive, its just that i either have to pay a ton of shipping for 12 bricks, or drive for about an hour to get them. 

I take it i should just take the ones that can take the most heat? or is 1260 C enough? They go up to 1650 C.

Since i will be using my shed i planned to put the oven outside to save space on my table and just keep the anvil inside of the shed. If i where to put the forge inside of the shed and there would be co2 problems they could just escape trough the roof/open door since nothing is insulated.(its made from corrugated plate at an angle, since co2 is somewhat lighter then air it would rise to the roof and go outside.)

 

Mod note: CO2 is heavier than air and will pool in low spots.

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NOT CO2, CO!  Carbon Monoxide not carbon dioxide!  The difference is a killer! There are holes in your roof to let it out?  Easy way to check out the ventilation is put a smoke source inside and see if it rises and escapes or builds up and lowers.  I visited a Celtic Round House once with a fire in the center of the floor and no chimney, the smoke made it's way through the thatch and door.  If you stood up in it you were smoked out of it, if you sat on the floor it was warm and dry and comfortable. CO is odorless, tasteless and deadly.

Keep the bricks dry if outside---they last longer.  If you won't be forge welding in it; then the 1260 C/2300 degF ones should work fine.

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oops, made myself a type-o there. Yes, there are holes, the corrugated plate are just nailed to a wooden beam, so there is a lot of nice air holes.

I have not been able to find the design Frosty posted, must be blind, will keep looking. 

Forge welding, had not even thought of that, since i will have to drive to go get them i might as well just get ones that go over 1400 C then.

 

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35 minutes ago, Deimos said:

since co2 is somewhat lighter then air it would rise to the roof and go outside.)

CO2 is not lighter than air.  It is heavier and will pool in low spots without proper ventilation and air movement.  CO has the same molecular weight as diatomic nitrogen which composes over 70% of the air around us, so it tends to disperse more or less evenly in the air.  Both are colorless and odorless and can cause death through overexposure.  The difference is that CO binds to the hemoglobin in your blood and it takes a fair amount of time for your body to recover from exposure.   CO2 does not bind to your blood, so mild to moderate exposure does not require any lengthy recovery time.  However, if there is enough CO2 in the air around you, it can displace the oxygen you need and essentially suffocate you gradually before you realize what is happening.

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All the info there is pretty overwhelming :wacko: Especially with translating all the terms and brands, and trying to find the dutch versions of everything.

But at least now i know i need a new design. ^^

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My first Insulating Fire Brick (IFB) forge was built with angle-iron and threaded rods, as it's one of the simplest designs for beginners.  I fitted an angled side-mounted burner, rather than a top-mounted one, to avoid the burner pipework over-heating when the forge was turned off.

If you block-off some of the end openings with spare IFB's, then the forge can get plenty hot enough for a beginner.

IFB_Forge_side_burner1.jpg.5a857aeeb0d1b134adf69a3b25c7ec4a.jpg

IFB_Forge_side_burner3.jpg.3690e8e90820c0bd15addfaf8a3b6098.jpg

 

Insulating Fire Bricks are easy to cut with an old saw (which will then be blunt!), and you can recess the end of your burner into the inner wall of an IFB, so that your burner tip doesn't melt.
IFB's are fragile, and will crack after a number of heat/cool cycles.  Coating the inner surface with a suitable "Flame Face" coating will make them last longer.

I believe the recommended coatings are Matricote or Plistex, but I used a DIY mix, as it was easier to get the materials in the UK.

Good luck with your build.

Tink!

Tink!

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To add to Buzzkill's comments about CO2:  The fact that CO2 is slightly heavier than air is why the "smoke" generated in theaters and movies which is actually CO2 or what is coming off dry ice clings to the floor.  That is why you see actors or dancers wading around in "smoke" up to their knees.

"By hammer and hand all arts do stand."

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Thanks for correcting me about the CO and CO2, the source i used also confused the two.

44 minutes ago, tinkertim said:

IFB's are fragile, and will crack after a number of heat/cool cycles.  Coating the inner surface with a suitable "Flame Face" coating will make them last longer.

I believe the recommended coatings are Matricote or Plistex, but I used a DIY mix, as it was easier to get the materials in the UK.

Can find nothing about those two brands being available over here, and the shop that sells the stones only has some heatproof mortar.

Will the stones just crack, or will they fall apart? And can you still use the forge if a stone is cracked?

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Hi Deimos,

The angle-iron and threaded rods generally keep enough tension on the soft fire bricks, so that it will still hold together and be usable if it cracks.

It is more the granular nature of the surface of the soft fire bricks that suffer most after heat/cool cycles.  Filling this open surface with a protective "Flame Face" coating makes it tougher, and less likely to crumble with the high heat of forging.

Be aware that all forge lining materials are "disposable" items, and will need to be replaced over time. The more expensive refractory coatings, such as Kast-o-lite30 have a much, much longer lifetime that Insulating Fire Bricks (IFBs), but a beginners forge made out of IFBs will allow you to learn a lot.

If you cannot get Matrikote or Plistex easily in NL, then you could try the DIY flame-face mix I use.  It works well on IFB's (which I have on the floor of my second forge design).

I have to go for now, but will post up some more info later if you are interested.

You could check out my posts in the "Problem with Forge. Welding Temps" thread if you like.

Tink!

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Thank you, that is why my design also clamps the top and lower half together, M10 treaded rods can take a lot of force. And i plan on make metal frames that keep the top and bottom bricks together. 

I have been looking very hard for refractory, and i can find some things. I can find mortar, cement and concrete. I take that the mortar is useless and i should go for cement or concrete. But from what i can find those only withstand up to 1200 C. Both Matrikote or Plistex are not for sale over here, and i can find nothing about kiln over here, since it translates into the dutch word for oven. And adding coating just gives me black paint for the outside of you cast iron stove.

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Hard refractories are available most places. Perlite is a gardener's soil additive available most places; mix them together for a workable alternative to insulating hard refractories like Kast-O-lite 30. Can't find the bricks you want? Turn your homemade refractory into bricks. This worked for home casting hobbyists for years before Kast-O-lite 30 was available. My first casting furnace had a two inch tunnel wall made of it, and it got yellow-white hot inside. The main difference between a tunnel forge and a casting furnace is that one stands vertical and the other rests horizontal.

One third Perlite to two thirds refractory by volume.

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Try calling ceramics or potter's suppliers and see what they use and sell to protect the inside their: kilns, pottery ovens, furnaces, whatever they call them from molten glazes. Have a notebook handy so you can write down the correct terms and tell us in a post. 

One of out members in the low country was doing some darned good experiments making kiln washes and refractory tiles. He was mixing SMALL amounts of Bentone and Zircopax, 3% and less Bentone to 97% or greater zircopax. I believe he found the Bentone at a ceramics supply.

Below is a pic of one of the bolt together forges and burners our club put together in a workshop. I believe something like 30 were made in an afternoon. We used Morgan Ceramics K-26 IFBs. They take the rapid thermal cycling found in propane forges. 

They reach welding temps easily with a single 1/2" T burner, as pictured. This forge had been running maybe 3-4 minutes when I took the pic.

Frosty The Lucky.

1517978216_Noweldforge08sized.thumb.jpg.c6e1f491bfef380badbcc0d2b3a133cc.jpg

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Words are a problem cross languages; like there are several languages where the word for charcoal and the word for bituminous coal is the same word and it's a modifier that indicates whether it's the plant based or the mineral based one. 

So instead of Kiln; what do you call the furnace that potters fire pottery in?  The Netherlands is famous for Delft pottery after all.

And THANKS Frosty for yet again posting the picture of the forge I was talking about!

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Nice touch with the sliding doors, really like the design.

Like i said, i could find some stuff, but it is all rated at temperatures lower then 1200 C, since it need to protect the bricks i take it it needs a lot more heat then the bricks?

2 minutes ago, ThomasPowers said:

So instead of Kiln; what do you call the furnace that potters fire pottery in?  The Netherlands is famous for Delft pottery after all.

That would be a ceramic oven, or a pottery oven.

Will keep looking, and start just calling companies, the internet is not my friend at the moment. 

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Hij Deimos, 

Looks like you are on your way with the right kind of bricks. If you need some pointers to local sources that have online shops or if you have trouble translating parts/things shoot me a dm. The ceramics supply in Haarlem I got some of my stuff from has a webshop too. 

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  • 2 months later...

Got the coating done and tried her out today,

 20210113_183053.jpg.1ea1c31a9dbdb085422670ca0267b24d.jpg

Closing of the back helps a lot with the heat, could not really close of the front like I wanted because the pieces I was working on where pretty small and I really need better thongs (get yourself some wolfjaw thongs, they are wonderfull for everything.... unless it any other shape then round...)

She gets pretty hot, and a lot faster then I expected, but I have not been able to burn my metal. Will try again tomorrow with a more closed of front. 

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More thongs when blacksmithing?  I'm not sure any of them are truly better or worse for our application. Hopefully you are wearing something over those.

To my eye the flame shape looks good, but it appears to be burning fuel rich if the color in the picture is what you are seeing with the naked eye.  If you open the choke a bit that should help you get an even hotter forge.  I'm looking forward to seeing what you do with it.

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Got to keep the wife happy, so its just thongs, clogs and apron ;)

It is a very blueish flame, picture is pretty much how it was in real life. I think the choke was about 4mm open. I opened it further at first but did not see any changes, will take of the training wheels and crank it up to 11 tomorrow. 

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