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forge wont get to forge welding heat?????!!!!!!!?????!!!!!


Trip

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Hey yall,

well I have tinkered with this fire pot so much that it's got me pullin out my hair, and about to start building a gas forge!!!! LOL

My fire pot just will not get to forge welding heat, no matter how much air it gets. At first I thought it was to deep (5 inches) so I rebuilt it to where it was 3.75 inches deep. It is 10"X12", and has a 3" air pipe to it, and a clinker breaker.

So unless I a missing some thing on the fire pot build, I am starting to think that its my coal, but I don't think thats the issue.

Any idea's on what's going on here????

Thanks,
Trip

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Hi Trip, Have you lit it?

Depth of firepot should not matter that much, do you have pictures of the firepot empty we could see?

What size apertures do you have for the air to feed into the bottom of the firepot ?

What provides your air source and is it adequate ?

How do you control the air blast ?

Wherabouts in the fire are you positioning the metal ? Too low and it won't reach welding heat, too high and similarly it won't reach welding heat.

Try using charcoal as test run, if that works it may be the fuel you have been using,

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You can reach forge welding heat with good coal in a hole dug in the ground with an air supply. With that in mind you should be able to sort this out!
Thinking or wishing you have good coal will not change wot it actually is.
You did not say wot your air supply is. A lot of air supply items are not suited for forges. You made yoiur firepot shallower and that leads me to wonder if your steel is down near the bottom of your fire and the air supply is cooling the metal and not letting it come up to heat.
yoiu also did not mention wot steel kind and size you are tryhing to weld. Mild steel takes more heat than high carbon. Some kmild steels are harder to weld than others. If you are tryig to weld stainless that is a whole different deal. and may have to wait til you solve these issues and get someyears behind you.
If you want help; on this you need to visit other smiths that use coal and see what they are using and how they are set up. Tale some of your coal with you and see if they will tlry it. `Everything I have mentioned here has been covered in this forum. and likely there are other tips that may be of value to you.

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I have used 3 differnt types of air suppliers. An electric blower, a10" "Tiger" hand blower, and a 16" Champion 400 blower. The "air hole" in the bottom of the fire pot is a 2"X1.5" hole. I have tried setting the metal across the fire pot, down in the fire, and above it, and 7 other way's from sunday, it just won't get hot!!!
I am trying to weld mild steel. I am wanting to get my forge welding skills up so that I can take a class next spring on hand forging wood working tools (axes, chisels, draw knives, adzes, spoke shaves, ect) what's funny is that I could weld pretty good in my old brake drum forge, but with this thing, it just won't get hot enough....
I have read a lot of the threads about fire pots, and have tried some of the idea's presented in them, but no luck..... If I had the $$$ I would just get a cast fire pot and be done with it, but at this time, that's not an option. :(

I will got out to the shop and get a pic of the fire pot so yall can see what i'm talkin about.

thanks
Trip

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The pic seems to show a square hole, 2" x11/2" seems to me to be small. if you neck down your air supply if will increase the pressure a bit and that may lower the volume you use. I still wonder about your coal and stick with my suggestion that you visit another smith.
We know wot you are doing is not working. That is not likely to change unless you find the problem and know wot you need to change. Even if you remake the fire box, redo the plumbing and or change coal It is still a guess as to wot the forge will do at each step.
Step by step go over wot you have created and compare with forge designs on this site that work. Proven designs are the ones to copy. You mentioned buying a cast firebox. Wot are its dimensions? all of them? Wot its made from has to do with longevity. Steel plate or cast should work if they are made right.

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The pic seems to show a square hole, 2" x11/2" seems to me to be small. if you neck down your air supply if will increase the pressure a bit and that may lower the volume you use. I still wonder about your coal and stick with my suggestion that you visit another smith.
We know wot you are doing is not working. That is not likely to change unless you find the problem and know wot you need to change. Even if you remake the fire box, redo the plumbing and or change coal It is still a guess as to wot the forge will do at each step.
Step by step go over wot you have created and compare with forge designs on this site that work. Proven designs are the ones to copy. You mentioned buying a cast firebox. Wot are its dimensions? all of them? Wot its made from has to do with longevity. Steel plate or cast should work if they are made right.


My fire pot is made out of 1/2" thick dimond plate steel, is 10"X12"X3.75". Here is a link to the cast firepot I would like to get https://www.blacksmithsdepot.com/page.php?theLocation=/Resources/Product/Forges_and_Parts/Fire_Pot_with_Tuyere_and_Ash_Dum.xml/

I also need to redesign my clinker breaker. The coal I use will form a clinker that covers the bottom of the firepot and
s 1" thick, So obviously the clinker breaker I am using, isn't doing it's job.

I've read several more threads on IFI, and got some good idea's, so I'm heading out to the shop and be like the mad scientist....... or mad blacksmith in this case. ROFLOL
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Hi trip,
To quote you, "what's funny is that I could weld pretty good in my old brake drum forge, "
Was that the same fuel you are using now?
if so the fuel is fine, so it must be something wrong in your setup.


it was coal....... I just pick up free coal where ever I can find it, but when the coal I am using now is gone, I am going to Cumberland Elkhorn, and buy some regular "blacksmith's coal".
so as far as I know it was the same stuff.
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can you burn your steel in it? if you can burn your steel you are past welding heat. if it clinkers up fast, and with the size of clinker you are talking about you are burning up a lot of iron, have dirty coal (lot of ash and moisture) or are not getting a good coking before you weld. are you coking up your coal into a coke cave? it works better with some coals and forges.

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can you burn your steel in it? if you can burn your steel you are past welding heat. if it clinkers up fast, and with the size of clinker you are talking about you are burning up a lot of iron, have dirty coal (lot of ash and moisture) or are not getting a good coking before you weld. are you coking up your coal into a coke cave? it works better with some coals and forges.


The coal I use won't "cave up", so what I do, is I coke my coal up from the sides.
I have burnt up small metals (1/4") but never any thing bigger than that. I have tried!!! LOL don't here of to many folks TRYING to burn up metal do ya???!!! LOL

Got a cardboard pattern cut out for a new fire pot, with a bigger "air hole" and clinker breaker. I think the reason my clinkers won't go in to the breaker is because it had to much of a "floor" and not enough of a hole. Just a thought. So with the new firepot it will only have 0.5" of "floor" on all sides, so that the only place the clinkers have to go is down through the firepot.

Trip
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Looks like you are burning anthracite and it looks like you have a lot of ash mixed in with it. You will be better off when you get some bituminous coal.

You know there is sometimes too much air blast. If you are blasting more air then can be consumed by the fire what is left over will actually cool you steel.

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Looks like you are burning anthracite and it looks like you have a lot of ash mixed in with it. You will be better off when you get some bituminous coal.
You know there is sometimes too much air blast. If you are blasting more air then can be consumed by the fire what is left over will actually cool you steel.


That's one thing I am sure about, is that it is Bituminous coal, and I made a sifter that takes out all the ash.

I'm hoping that my new firepot will fix the problem, we shall see!!!!!
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People need to understand as coal goes anthracite is as closes to coke as you can get in a coal. it is the best coal to forge with because it takes little time to get to coke. as for your coke cave, do you wet your coal? if not that will help it to stick together as you steam the coal to coke.

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People need to understand as coal goes anthracite is as closes to coke as you can get in a coal. it is the best coal to forge with because it takes little time to get to coke. as for your coke cave, do you wet your coal? if not that will help it to stick together as you steam the coal to coke.


Matto, are you sure about that? I don't think that anthracite cokes up at all, it just burns. When coal forms it is bituminous first and then metamorphicelly converted to anthracite under extreme heat and pressure. Not much volatiles left after the conversion.

Coke is made when you burn off the volatiles from soft bituminous leaving almost pure carbon.
It bubbles up as the tars burn off and forms a kind of crust that forms that nice cave.
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you are right , what i was taught was to use it like coke. the man that told me about coal and its uses has a double phd in chemistry and started the wyoming anylitical labratories. he developed some of the grading systems for anylizing coal content all over the world.
anthracite has the highest carbon content and the lowest ash and moisture content of all coals. it is basically all carbon. so to use it you have to burn it like you would pure coke.

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just a side note, as i was tought the grading of coal is as follows ; you start with the lowest grade which is lignite,(brown coal or boiler coal) very high ash and moisture content, dirty coal and is manily what is shipped all across the U.S. going to power plants. next is sub-bituminous which appears dull black has a higher carbon content than lignite and lower than bituminous. less moisture and ash than lignite, then you get to "blacksmiths coal" bituminous, (hard coal) has low ash, sulfer and moisture content has great coking ability. anthracite contains the lowest moisture and ash content and the highest carbon content of all coal types. it is as close to pure coke as you can get in a coal. using anthracite you have to wet and pack it to get it to "stick". Bealer talkes about it in the art of blacksmithing.
andrews in new edge of the anvil list the types of coal, Sims in the backyard blacksmith also has this list. Dr. Leroy Jacobs, of the wyoming analytical laboratories, who i smithed a lot with and has developed some of the grading systems for coal lists the same way. he also agrees that bituminous is the most used as blacksmithing coal. i also agree 100% that bituminous is one of the best coals to use for its availibility and versitility, it is tried and true, as blacksmiths coal in all books i have read and by all smith i have talked to. i think anthracite gets a bad rap because smiths don't burn it right and it is harder to find and use. it also cost more.

this is just some of what i have learned over time in blacksmithing about coal, but if any of it is wrong please let me know i don't want to be telling and teaching wrong information.

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From everything I've read so far it sounds like you have a load of poor coal Trip. Sure it may be bituminus or maybe sub-bituminus which is pretty poor. Regardless it may be from a coal shale seam, good for boiler or power plant use and nothing but clinker stock in a forge. I have a big old batch of shale coal I dug at a local mine a few years ago and from a seam of otherwise superb metallurgical coal. Stuff fooled me like a chump but I got over it, it still looks prime.

You've built one good forge so I doubt strongly you've made a significant mistake on this one. Sure there are details where improvement can be made but I'd be surprised as Santa and Mommy that Christmas eve if you'd done something fundamentally wrong.

So, before you start rebuilding your forge try picking up some bona fide blacksmithing coal and see how it works. I'm betting you'll be pleasantly surprised.

Frosty The Lucky.

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From everything I've read so far it sounds like you have a load of poor coal Trip. Sure it may be bituminus or maybe sub-bituminus which is pretty poor. Regardless it may be from a coal shale seam, good for boiler or power plant use and nothing but clinker stock in a forge. I have a big old batch of shale coal I dug at a local mine a few years ago and from a seam of otherwise superb metallurgical coal. Stuff fooled me like a chump but I got over it, it still looks prime.
You've built one good forge so I doubt strongly you've made a significant mistake on this one. Sure there are details where improvement can be made but I'd be surprised as Santa and Mommy that Christmas eve if you'd done something fundamentally wrong.
So, before you start rebuilding your forge try picking up some bona fide blacksmithing coal and see how it works. I'm betting you'll be pleasantly surprised.
Frosty The Lucky.


You might be on to some thing.

The coal I am using was given to me, by a elderly man about 0.5 hour from me. He heats his house with an old coal boiler, and he only likes to use the bigger coal, so he sifts out the smaller stuff, which is the perfect size for blacksmithing. He gave me about 2 tons, and said that I can get another 2 tons this November. But it this is what is causing my "high blood pressure" then I might have to say " Thanks, but no thanks".
I found a place that sells "blacksmithing coal" and it's priced at $400.00 per ton, and it will cost me about $100 to go get it, so i'm looking at $500.00 a ton. Is that a fair price, or is it kinda high? thinking about going to a gas forge, but I don't know.

Thanks,
Trip
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Sounds like your clinker may be part of the problem. A heavy clinker or a lot of as can plug things up to the point where you are not getting a good fire. No clinker breaker will not remove a big clinker on the bottom of your fire. I find the best bet when I am getting a clinker forming is to let the fire cool for a couple of minutes so the clinker will solidify into a ring and then hook it out with a poker. Some coal will not form a ring and some makes mostly ash but it sounds like yours is forming a mass.

Also you say you have a 2"x1.5" hole which could be bigger but you don't mention how big your clinker breaker is? If you don't have a gap 3/8-1/2" either side of the clinker breaker you are not going to get enough air. Try removing your clinker breaker and just putting a 1/2" bar down the middle. You may find that is your problem.

I have a ton of coal I got for free that is not that good but is not bad and I often burn metallurgical coke because it is cheap and because of the lack of smoke. But I keep a couple of bags of good Pocohontis coal around in case I need a particularly hot fire. I will often toss in a handfull or two of the good coal to help keep the coke lit or to juice up the free coal. You might try a couple of bags from a blacksmith supplier to see how it compares to the coal you are getting. It will be more expensive by the pound than the blacksmith coal you are thinking of buying but it will be cheaper than buying a ton of coal only to discover the coal was not your problem.

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Well yall, I just thought I was going to have a new firepot, but I welded the "tuery?" backwards, so it wouldn't fit in my masonry forge. SOOOOOOOOOOOOOO

I took out my existing firepot, took out the old clinker breaker with a cordless sawzawl, raised the bottom plate up to where it was 3.75" deep, and made the bottom hole bigger (2.5"X2"), and put in a piece of 3/4" rebar in the center of the hole.

Also I disconected my electric blower, and hooked up my big 16" Champion 400 blower.

I guess all that fixed it, because I just did my first successful forge weld, since having this masonry forge!!!!!!!!!!! I am one HAPPY country boy!!!!!!!!!

so I guess I will make a mobile steel forge out of the extra firepot.

Thanks for all your help yall,

Trip

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