Fuel Burn Duration Inquiry

[edv7028]

Hi to All...

I just now joined this group because I've recently made a small forge out of some old Chevy Suburban Brake Drums. I've tried only Mesquite Wood Chips & Twigs as fuel so far; and found that I can heat 1/2" rebar hot enough to bend into a circle by hand only.

I've tried spraying old engine oil, cooking oil, and old diesel onto the fire to attain higher temps; but am still working on an automatic spray mechanism to get this done at a later date. From what I've read, it'll make lots of difference. As is, I can melt about 100 beer & soda cans in about 20 minutes, or as fast as I can throw them into the top inlet. I can also melt glass in about 2 minutes per bottle. This is irrelevant; but I only offer it as an F.Y.I. in case anyone cares.

If anyone has ever tried "Deer Corn" as fuel, I'd be really interested to know how well that works. I've read about many Home Heating Systems that use corn as fuel, along with wood pellets, Walnut Shells, etc.

I found some Bituminous Coal and Coke 2 days ago, and before I waste too much of it, wanted to know if anyone can tell me the temperatures that each can reach, and how long a 1 pound coffee can of each can burn given the same amount of air/fan speed.

Oh yeah... if anyone can give me a bried instruction on how to actually "Weld" metal together in my type of forge, again I'd appreciate your info.

Thank You !

Ed VA

[TASMITH]

I can't quote exact temperatures on burning coal or coke but I can tell you that coke burns at a lot higher temp. than coal does. Coke is coal that has had all the other volatile products ( such as benzene, toluene, tar. light oils, to name just a couple of the over 500 different chemical compounds contained in coal) driven out of the coal by heating it in the absence of air(in coke ovens). After processing what is left is about 90 to 95 % pure carbon. This requires a constant air flow to keep burning, were-as coal will continue to burn without a steady air flow.Coke produces very little flame (usually a light blue) but is the best fuel for a forge.When using coal you are basically reducing it to coke but are doing so in an open environment and thus you get more smoke(Volatiles burning in the coal) and significantly more flame but not the same heat value as coke.
Most Blacksmiths use coal or charcoal simply because it is far more readily available than coke. One other point I should make in the coal versus coke, is that the firepots are different for each of these products. Coal firepots are deeper( generally 6 to 8 inches) and are usually made of steel. Coke firepots are much shallower (and usually round) about three to four inches deep, and are made of cast iron. Coke pots are made of cast iron for the fact that coke does indeed burn much hotter than coal and would burn out a steel firepot much quicker.

Terry

[David Einhorn]

All of the firepots that I have are old, one Buffalo and a couple of Champion brand. These older firepots are cast iron. Cast iron holds up better to high temperature, from what I have heard, because the lower carbon content raises their melting/burning temperature. These firepots were used, and I still use, Bituminous Coal. I guess I am out of touch with modern firepots as I thought they were still being made of cast iron for people using coal.

If you look in some of the older books emphasis was placed on adding coal to outside of the fire and gradually working the coal inwards as the center of the fire burned out. Water was sprinkled on the coal outside of the firepot area to keep the fire under control and build up coke walls. The end result is that by the time the coal reached the firepot the fire was comprised of coke, and smoke was minimal. This hot coke fire needed a cast iron pot if the firepot was to last very long.

At least that was the way things were in the stone-age when I bought my equipment, perhaps someone could enlighten me on what suppliers of blacksmithing equipment are now using for materials in making their firepots.

[Steve Sells]

Actually cast iron has a higher carbon content, well over 2% C.

Its melting point is higher than steel because while the addition of carbon does lower the melting point of iron, this is only true until reaching the eustetic point, which is around 0.83%C, then it raises the melting point of the mixture again.

A second point I wish to comment on, as my Opinion only, is I have heard, and therefore assume that cast iron pots are made because casting steel is not as cheap as casting gray iron. It took me over 15 years to get a small hole in my last steep pot, and in fairness it has been outside exposed to the rain the last 6 years or so.

[dablacksmith]

well ide say as far as fuel goes coal or coke are going to be better than misquite chips . coke takes a fairly constant air supply to keep it going . what that means is if you are useing a hand crank forge or bellows (i do) then you cant stop pumping for more than a few minutes without risking haveing the fire go out! it is virtually smokeless after initial fireup tho and produces more heat per pound than coal.there are better and worse grades of bolth coal and coke and most places will give you a information on their coal like btu output ash content sulfur ect... that is a good way to compare two different brands of coal.as far as burn time it varys a lot from good to low quality! ive had coal that a bag would be used up in a day ! and the coke ime useing currently lasts about a week of forgeing .that is 5 day week 5-6 hrs a day... cirn walnut shells ect are fine for heating a house but probably not a good fuel for forgeing ... coal coke charcoal propane natural gas electricity are the comon fuels used to heat steel to forgeing temprature.as far as firepots go ive use all kinds and really havnt noticed a big difference on longevity between useing coal or coke... shouldnt make much difference one way or another the main difference i see is coal can coke up and form an "oven" to keep in the heat .. that is handy sometimes but ive gotten used to coke and dont miss the smoke!! good luck!

[Flaming S Forge]

I tried corn one time. My coal fire was almost out when I decided to try some corn that I had on hand. I started putting it into the forge, turned on the air and in no time it was blazing away. No real smoke or harsh smell. For a little test of the heat output, I got out a railroad spike and put it into the fire to see how hot I could get it. It didn't take long to get to a yellow heat. I have a picture attached showing the spike. The only negative I found with the corn, it burns at a faster rate than the hard coal I was used to using. If I ever get a good deal on a large load of corn, I wouldn't be afraid to use it.

[tech413]

Corn eh??? hmmmm..... being on the farm I have access to TONS of it, I might have to try it out. Thanks!

[edv7028]

Hi & Thanks to All of you folks for your input...

Flaming S Forge... Your info was Great and I really appreciate the photo. Here, 100 pounds of corn is about 1/3 cheaper than 50 pounds of Coke or Coal; so I was interested to see if it worked, and how long it lasted. Your info was really helpful. Thank You !

I cranked up my forge today, trying to practice with lighting the coal and/or coke. It took me quite awhile to get it started, not knowing which I should have put in first, or at least not knowing which fuel was which. Anyway, I finally got it going; and proceeded to melt a bunch of cans and bottles. I had my Squirrel Cage Fan running at the top end, and the flames were blasting out the top of my forge. It worked GREAT !

I put an old empty 5 gallon kerosene can with the top cut out on the bottom, then cut a square hole in the side for the Squirrel Cage Fan's output. On top of this, I have one Brake Drum lying there as the firepot, and the other on top facing downward. There is a Perforated Stainless Steel Screen on the bottom to allowthe air in, and keeping the fuel from falling out. The melted aluminum, glass, lead, simply melts through the perforations, and is collected in the bottom of the kerosene can. I've already collected about 5 pounds of melted aluminum for recycling like this. Saves lots of space in the trash bags !

It didn't cost me anything except the 1985 Chevy Suburban which burned-up, and 1 cut-off wheel which is only partially used up. Oh yeah... it also took 2 gouging rods to burn a 2 inch hole in the side for a Hair Dryer Air Input which I no longer need.

"Cheap is Good !"

Thanks Again !

Ed VA

Edited December 20, 2008 by edv7028

[Steve Sells]

you do realize that you may be losing about half your aluminum cans in weight when melting them? that is why few use them as stock for casting.

[jayco]

Ed ,you mention spraying old engine oil and old diesel on your forge as a way to obtain higher temperatures.
I must tell you that both of these are dangerous to use in your forge.
The fumes from old engine oil are toxic.
Also, there is danger from flash fires as well.

Be careful!

[Glenn]

Read this link about used motor oil

Read this IFI thread

[edv7028]

Hi Again...

Steve Sells... Good Thinking about losing some of the weight as I melted those cans there Steve. It hadn't occurred to me; but I'm fairly certain that when I was using Mesquite Wood, I didn't lose much. Now, with the Coal and Coke, I have No Doubt Whatsoever that I'm losing LOTS of that Aluminum Weight. Before I can let loose of the can as I'm putting it into the top inlet, melted droplets of Aluminum are spewing out of the forge. It doesn't even take 2 seconds for the cans to melt/vaporize ! At least I burned an entire 55 gallon trash can of cans in less than an hour. Most of this time was handling the cans, and tending the fire.

By the way... does anyone have any idea what percentage of Coal/Coke turns into what you all call "Clinkers" ? Say for example that I put a one pound coffee can of each into the forge, and burn it, how much, (or how Many), "Clinkers" should I expect ?

Jaylis ???... Thanks for the warning on the burning oil/diesel. I did stay up wind of the fumes, and did lots of dancing around trying to stay out of their way. Not only are they injurious; but they stink !

Thanks Again !

Ed VA

[edv7028]

Hi Flaming S Forge...

How long does say a 1 pound coffee can of Coal or Coke Burn in your forge when you have your air system turned on high ?

How much Corn did you put into your forge; and approximately how many minutes did it burn for you ?

How much/many "Clinkers" do you usually get from a 1 pound coffee can of Coal or Coke ?

Thank You !

Ed VA

I tried corn one time. My coal fire was almost out when I decided to try some corn that I had on hand. I started putting it into the forge, turned on the air and in no time it was blazing away. No real smoke or harsh smell. For a little test of the heat output, I got out a railroad spike and put it into the fire to see how hot I could get it. It didn't take long to get to a yellow heat. I have a picture attached showing the spike. The only negative I found with the corn, it burns at a faster rate than the hard coal I was used to using. If I ever get a good deal on a large load of corn, I wouldn't be afraid to use it.

Edited December 21, 2008 by edv7028

[edv7028]

Hello & Thank You for your links to those reports on burning oil.

I have logged onto your website about 3 or 4 times; and the last 2 times, I keep getting an error which disallows reaching you. The error is...

"Access Violation at Address 0000000".

I have never had this error on any other website in the 4 years I've had this computer; so I'm guessing the problem is at your end. If not, and you know of anything I can do, please let me know the procedure.

Thank You !

Ed VA

Read this link about used motor oil

Read this IFI thread

[Flaming S Forge]

I really can't give you an accurate figure for corn consumption since I only used it that one day more as an experiment. When I'm using coal, I just shovel on more as needed and never really kept accurate account of burn duration. If I run my forge mainly wide open when heating large stock, I will use about 30lbs of coal in an 8 hour period. If I'm working with small stock, I don't need near as much air flow and I use less coal. For your answer on clinkers, that depends on the quality of the coal you use and the air flow. When I'm forging at a lower air flow, my forge burns the coal up into a nice powdery ash residue with no clinker problem. However, if I am blasting it with full air output, I will get some nasty clinkers which if not managed properly will rob the fire of true heat potential. I guess the best answer I can give you is do some experimenting yourself. Since no two forges and fuel combinations are 100% identical, you have to find what works best in your forge setup. You asked about coke. Since I only use anthracite (hard coal) I don't get any coke. It burns to ash. What I like about hard coal is virtually no smoke or smell. Only have some smoke when starting it with kindling. I have my forge vented with only a 7" pipe and my shop stays smoke free. I do have a constant flow of fresh air coming into the shop at all times because of the potential of carbon monoxide. Also have a carbon monoxide detector next to me in my forging area. I hope some of this rambling has answered some of your questions. Why don't you edit your profile as to your location. Someone might be close to you to offer additional help. One other thought, when you have a good fire from a safe fuel of choice, you don't need to add any accelerent to the fire. You will have more than enough of heat to get your job done safely. Good luck.

[edv7028]

Thank You Flaming S Forge !

Sorry to keep bothering you; but you seem to have tried lots of the stuff I'm trying to learn about.

Gee... 30 pounds in 8 hours ?!?!?! I have this 50# bag that I was hoping would last me MONTHS ! I hope it gets cheaper if I expect to accomplish anything.

As I mentioned in an earlier post, I had one Really Beautiful Fire going yesterday in my Brake Drum Forge where the 3/4" thick Brake Drum got to glowing Cherry Red. I had my Squirrel Cage Fan running Full Bore; but being a small fan, it's nothing really impressive. Anyway, I had what I'm assuming are lots of those "Clinkers" after the 1st burn. I cleaned out the forge, started another batch of Coal/Coke Combination, and then re-burned those "Clinkers". The Leftovers got considerably smaller; so I guess those "Clinkers" will burn too if I get them hot enough. I don't know.

I'm still having problems getting my Coal/Coke to ignite, even with the instructions I found on this website. Finally, I got a combination of wood chips and candle wax into a pile at the bottom of the forge, put a little Coal/Coke on top, then lit it up. So far, this has been the easiest way to get everything burning; but it still took me about an hour.

The weather here has been foggy/misty for several days; so I was wondering if my Coal/Coke has absorbed any of that moisture, and now will not catch fire as it should. If you have any input on this, please let me know.

I'll add some info to my profile in case it helps anyone's answers to my questions. As always, I Thank You All !

Regards,

Ed VA

Edited December 21, 2008 by edv7028

[Flaming S Forge]

Don't be afraid to ask all the questions you have. The guys here have an abundance of knowledge and are more than willing to help. As far as starting your fire, here is what I do. I'll put some very dry kindling wood in the forge by itself with no coal. I take my propane torch and light the wood with full air blast. After the wood is burning well, I slowly start adding coal around the outside of the fire. Then slowly working inward towards the center of the fire I'll add a small amount of coal. As the fire gets bigger I add more coal. I can usually get my forge up to forging heat in about 15 minutes time. The key is to add a little at a time and be patient. You mentioned that it was foggy and misty there a few days. Coal fires are affected by atmospheric pressure. Dreary days you have low pressure which doesn't let your fire "draw" as freely as on a nice clear sunny day. I have heated my home with coal for the past 37 years and I learned alot about what coal fires like and dislike. Today we are having freezing rain and snow here. I had to increase the air feed on my coal stove in the house to have an efficient burning fire.

[newbysmith]

I am a new smith and I am using corn. It does a good job. Cant find any coal around here close so $6 bucks for 60lbs of feed corn lasts me 4 weekends or so. Anyone tried wood pellets? Do they burn quicker than corn?