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New to the site and have a few questions on a build.


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Greetings all! I am new to this site and have read a lot of the posts, along with a lot of research outside this site. I do have a few questions on my build that I cant seem to find answers too. I have been told that 240-350 cubic inch per one burner. Which number is closer? I don't want to build a "cheap" forge, but I sure don't want to pay an arm and a leg for some thing I might only take up as a hobby. I do have a blower to use on build, but I have recently read that it might be too weak. CFM isn't listed. I want to say its 1550 rpm. Most likely its out of a old furnace. It also says  "#1 Thermal Protected" so I am not too sure if it shuts down at a specific temp or what that means. As for the burner(s) I have seen so much talk on one way or another for burner builds. My forge was going to be around 600 cubic inches. I do want to make it smaller if I can. I can get the ceramic wool in 1" or 2" from what I am told easily. (we will see when the time comes) Along with cast-able refractory if I need it. I was going to line the inside of the stainless steel shell but I was told it might break and fall into it. is this true? If I am doing a blower + propane setup do I need an elbow before it hits the burner? (to mix the gas I assume) There plans too be 3 doors on it. ! back door that I can take down if I need to do larger items, and 2 front doors that swing out and to either side with an exhaust hole in them when they are closed. There will be a small porch as well.  What (if any) is the ratio of burner to exhaust hole size? I plan on making it an outside forge, that is semi portable. If I make the bed or floor do I put it on the blanket or the cast-able refractory, or just cast it along with the rest the shell? As for the propane setup I was planning on running 1 BBQ sized bottle. Will it freeze up?  I'm sorry for all the questions, but from what I have read there is a ALOT of knowledgeable people here. Where I live I cant seem to find any one near that has any info. I tell people I want to build a forge and I get either "what's that" or "why?!" (mid west Montana) If there is any one that wants to talk one on one I will be fine with that as well. Just figured that a few of the many questions I had where not listed (or I overlooked them) in the forums and would be helpful for others as well. The more I know, the more questions I have it seems. I thought this would be some simple project in the start but I have created a monster of one for me! :unsure:

 

 

 

    P.S. I know this belongs in a different thread but I will ask here first since I have asked a lot from you guys/gals as is. I am also looking for an anvil but don't want to buy it if I cant see/feel it. What stores or places would have such an item that would be worth buying?

 

 

 

Again so sorry for the long post. I want to get this right and not have to scrap it and start over. If you need more info or questions for me please feel free to ask.

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Hi; I have a motor vehicle how much can it carry?  Of course I won't tell you if it's a smart car or a massive dump truck...

 

How big your burner is has a large impact on how much it will heat.  RPM of a blower is not strongly correlated to CFM.

 

Got a manufacturer's name on the blower?  Contact them and ask.

 

My 10" dia and 16" long pipe forge with 2" of kaowool is very nicely blown by a 150 CFM blower---I've accidentally melted steel in it before.

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Good Morning,

 

Start with a simple design of a forge, when you find you are working material larger than you can handle, build another one. None of us have only one forge. A forge can be made with a 2" Pipe TEE, it would work well for tiny things (tips, ends of bars, etc). It costs less and takes less time to heat a small forge for a small job, than waiting 1/2 hour for your forge to heat up so you can do something. Thomas was saying the same thing.

 

There is no perfect or this one is best. The best one is the one that will do what you want, the quickest and least expensive. The best forge is the one you have, not the bird in the bush. An Oxy/Propane rose-bud is a forge, just without the container.

 

A forge can be built with 9 fire bricks, no insulation necessary.

K.I.S.S. Keep it Stupid Simple. :) :)

 

Neil

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Probably the first mistake aspiring blacksmiths make concerning their decision to build a forge is the size of the forge.  It must be huge, because after all, someday the aspiring blacksmith wants to make a sword.

 

Build a small forge from a 3# coffee can using a venturi burner.  Learn how to do the basics.  Learn how to build a proper burner, how refractory coating improves the efficiency of the forge, etc.

 

I'm now on experimental forge #4 - it's a 3# coffee can with a pass-through hole in the back.  No, I can't do everything with this forge, but I can do 95% of the things that _I_ want to do at this stage in my journey as a beginning blacksmith.

 

As to anvils, get a 30-40" piece of railroad track and stand it on end - you'll have lots of mass and a fairly decent area to work on.  If you decide you don't want to keep smithing, you'd be surprised at how easily you can get rid of all of your equipment.  If you keep at it, you'll have a portable anvil to complement the 400# behemoth that you buy once you start making super-duper progress.  

 

I got my first anvil for free - because I let people know that I wanted to start the craft.

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I'm on my second gasser and my fourth solid fuel forge, sixth is you count charcoal and mineral coal as separate forges.

 

Get a burner into some sort of insulated forge chamber as quickly as you safely can and start using it, All sorts of ideas, improvements and revelations will be generated by the act of getting a fire going and heating up some metal in it.

 

Everyone's process is different, but we all heat metal.

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Mornin' people! Wow I wasn't expecting this fast of an awnser(s). Thank you all. I do understand I need to keep it simple. At my current living location I wouldn't have enough room to store more then 1 forge. As for the coffee/soup can setups, are they really that good? Yeah it might show me the basics, so that is a plus. However it just seems like a waste of resources to me. I suppose that I can build a small one to learn. then go from there.

 

 

As for the propane cylinder body style forge, is this one considered to be a very large one that you wont use much or just more of an advanced smiths forge? Reason I ask is my shell that I planned on using is near that size. (its an old stainless steel beer keg, pony size.) It already had a hole in the mid part for a burner and the exhaust hole is nearly the correct size from what I can gather.

 

 

 

As to anvils, get a 30-40" piece of railroad track and stand it on end - you'll have lots of mass and a fairly decent area to work on. 

 

I was planning on getting a huge chunk of RR rail 90 weight. 3-4 feet and 250 lbs of RR spikes. I was reading on what setup I should do to make the anvil and there was talk of the legality behind even owning such items. I talked to a police officer, and he said (very abruptly and angrily) "to even own them it is against federal law" so I asked if I got the RR to document the sale to me or some thing of that nature, he still said no, and if I am caught with it, im  in trouble. So I called my source back that works with the RR and he said yeah its a federal offence. So I didn't get any of it. ( I try to keep my nose clean) Is there a loop hole that I am missing?

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Owning chunks of metal that used to be rails or spikes is not illegal.  Stealing them from the railroads or trespassing on railroad property invokes a host of crimes.  Used rail equipment is sold every day - legally.  You can also buy brand new spikes by the piece or by the barrel.

 

Yes, a pony keg would make a lovely forge, but as a new smith start small - you'll save on gas and you'll get practical experience that won't cost you too much.  Propane is not free.  The more space you heat, the more propane you use.  As a beginner, heating space you don't need is leaving money on the table.  My coffee can forge is insulated with one inch of Superwool HT and painted with a reflective coating that reflects the heat back into the forge.  I can weld in it.  I work in small-ish stock (3/4" and below) but I have done 1" stock in the can - it just takes a while.

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Welcome aboard, glad to have you.

 

I think the officer might've been exaggerating a bit to maybe discourage you from scrounging along the tracks. THAT is a federal offense, don't do it, getting caught can result in a little graybar hotel time. You can buy rail and spikes from the RR at their salvage sales or perhaps the scrap yard, if they sell to the public, just get a receipt.

 

When I started figuring out propane forges I copied the Johnson Appliance 122 I had access to for measuring and have had good results using their basic ratio of. 1 ea. 3/4" burner outlet per 350 cu/in volume. the Johnson uses a blown (gun) burner and the same ratio works well with NA (Naturally Aspirated) burners.

 

I've had much better luck using multiple plies of 1" refractory blanket than thicker say 2". The 1" bends to fit the shell better, fewer and smaller wrinkles. In my first pipe forge I made a hard inner liner from a rammable high phosphate refractory with a 1" ceramic blanket outer liner. Worked well but kind of overkill.

 

For a pipe forge I like stainless steel stove pipe. It's available in many diameters and lengths, usually multiples of 2" for short lengths and the hardware is off the shelf. Wall hanger brackets make perfect legs, for instance. You can work it without special tools, hole saws, drill bits, pop rivets do the trick, nicely. Lining it with a ceramic blanket is as easy as cutting it an inch or so long and compression will hold it in place securely.

 

Using a good kiln wash like ITC-100 will help it survive welding fluxes if you're planning on welding. A split 3,000f hard fire brick makes a fine floor but a lot of guys use kiln shelf, both are dandy floors but both last a LOT longer with a kiln wash.

 

I don't know what kind of blower you're are referring to or what CFM you need. Check some of the commercial forge/burner manufacturers and see what they use.

 

Running the air fuel mix around a corner is a good practice to assist mixing and it helps prevent back firing though if you get a backfire going, just shut off the gas 1/4 turn ball valve is my favorite shut off, and do some tweaking on the mix or air speed. A back fire is when the flame front starts moving us the burner tube away from the forge chamber BACK towards the blower and if allowed to continue can do BAD things.

 

You'll see a lot of opinion about which basic burner design is better but they'll both perform well if properly designed and tuned. Beyond the obvious, portability, ease of construction and being tied to electric, both are more than capable of driving an iron melter let alone a welding capable forge.

 

Frosty The Lucky.

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Hey, thanks Frosty! You seem to pop up in a lot of different posts. Glad you could share your knowhow with us starters. Not too used to the people I TRY to talk to about my latest endeavor, and they have next to nothing to help me out. (At least around my town) This don't shock me much conceding I cant find an anvil that's more then 50 lbs to save my life. (I checked 20+ stores today alone)  

 

The elbow idea it is then. Is there a minimum CFM a blower should be to help prevent backfire?

 

 

I do plan on one day trying to weld. The "coffee can" forge that was mentioned previously, will it get to welding temps pending on the build, or is it just too inefficient?

 

 

Thanks again for the input, from all of you!

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Here's a 1/4" square bar loop weld.post-9780-0-94369200-1383837400_thumb.jp

 

It was done in this coffee-can forgepost-9780-0-04382300-1383837433_thumb.jp

 

I was using the burner at the right (3/4" modified Porter style burner)post-9780-0-14433800-1383837446_thumb.jp

 

In the first picture, the dark object is the #2 cat in the house, who insisted that she needed to be in the picture.

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Cool I might do that to start with then. get my foot in the door. The burner placement is right above? I thought that could cause problems with the exhaust going into the burner. Your focusing the heat right on instead of the "vortex" method hmm ok. I think I might have to hit the drawing board on my next free session of time. Thanks.

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You are correct!

 

When you have it at top-dead-center you need to use some scrap superwool (kaowool, etc) to stuff around the burner in the holder tube to prevent hot gasses from rising and messing with the burner's air intake.  In a forge this small it's hard to get a good swirl going (at least I've not had a lot of luck with that) so top-dead-center is my next choice.  Use the hot spot to your advantage!

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Ahh did you ask everyone in those stores about finding an anvil or are you dedicated to paying the highest possible price?

 

You probably want to buy a good condition used one from someone who has no use for it but wants to see it properly used.

 

I found one in just a day just by asking around at Church at the coffee hour after the service---they gave it to me too.

 

It's the people *NOT* in the business of making money selling anvils that will give you the best deals and to find them you have to

TALK TO EVERYONE!

 

Had a fellow here recently who kept wanting to just talk with tool dealers at the fleamarket.  ALL my anvil purchases that resulted

from fleamarkets were from people NOT selling tools; they didn't have the anvils on-site but back at home---less competition!!!

 

Lets see the ones I remember were selling: greasy car parts; plumbing supplies, cleaned out garages/basements and this was in

the middle of the city! 

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Jcornell wrote:

 

"When you have it at top-dead-center you need to use some scrap superwool (kaowool, etc) to stuff around the burner in the holder tube to prevent hot gasses from rising and messing with the burner's air intake. "

 

I have to do this, stuff a thin layer of scrap kaowool around the burner in the holder, to keep the heat from rising. I've got my burner tube mounted 15 or 20 degrees from top dead center. Heat rising was blistering the paint off the burner mount.

 

In retropect, I'd use a bigger burner mount as the 3/16 clearance between the burner and the mount is a pain to stuff with kaowool, have to carefully wedge it in with a popsicle stick. a nice 1/4 or 3/8ths clearance would be easier to plug.

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Ok thanks. As for talking yeah I been telling everyone I work with and places I go... Ie antique shop owners. My next bet is to start hitting the road and finding some farmers willing to talk. I still have a few tricks yet to try.

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My 2 cents on the forge subject is that the most important things in a forge is to have even heat. Saves a lot of time and hassle. Another thing is to have all of the oxygen consumed before the flame hits the metal to reduce oxidation especially when forge welding. And for it to heat up quickly. Also for the long term use of a forge, I would say if you are going to just be forging steel for the most part, use a venturi or naturally aspirated type of burner. If you are going to be forging aluminum, bronze or copper go for the forced air since it is easier to maintain a lower temperature on them. You can get lower heat on venturi burners but require more maintenance and dinking around to keep your forge burning smooth. Thats the burner part of it. Now for the refractory/insulator, you can go bricks, castable refractory or ceramic fiber blanket. Castable and bricks are more durable but need a longer heat up time and act more as insulators. Ceramic fiber blanket is a refractory/reflector and will heat up much faster because of less mass and the fact that it "reflects" the heat back into the chamber better. My preference is ceramic fiber with a 1" kiln shelf or Silicon carbide shelf and coat the fiber blanket with something like ITC 100 or slip to help keep it contained.

 

You mentioned stainless steel inner shell for your forge? I make all of my forges out of stainless steel since it will last much longer than steel when exposed to the heat up and cool down cycles. Use a stainless shell if you want, or steel. You will get many years of use out of both. What I wouldn't do is put any type of metal in the chamber of the forge other than what your forging. Always have the refractory on the inside of the heating chamber for maximum efficiency.

 

I have three forges. One for forge welding that can handle the corrosive nature of the flux, one forge for doing smaller stuff which is a two venturi burner type, and a two burner forced air large forge for doing bigger items and most of my bronze work since i can easily turn down the heat.

 

I wont get into burner design on this post but it is worth researching because they all work differently and some better than others.

 

The trick to getting that swirl in the forge chamber which contributes a lot to getting an even heat in the forge chamber is to have the burners coming in at a tangent and placed the longest distance from where the floor of the forge is. Think of the way a centrifugal blower is made but reverse the flow direction.

 

hope that helped

 

Monel

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Welcome aboard Monel, glad to have you. If you'll put your general location in the header you might be pleasantly surprised at how many of the IFI gang live within visiting distance.

 

Have you forged Monel? Any advice on alloy?

 

Frosty The Lucky.

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Welcome aboard Monel, glad to have you. If you'll put your general location in the header you might be pleasantly surprised at how many of the IFI gang live within visiting distance.

 

Have you forged Monel? Any advice on alloy?

 

Frosty The Lucky.

Done. And thanks for the warm welcome.

 

I have forged a good amount of Monel. I would say 400 but last I checked it wasn't being made anymore but any nickel copper alloy around 60/40 forges fine and welds like stainless steel. A cheaper option is a copper nickel alloy or cupronickel c71500 and looks virtually the same. Now is the time to stock up since the price of nickel has dropped from $22 to around $6.

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