samw1 Posted July 13, 2012 Share Posted July 13, 2012 Ok guys I'm having one heck of a problem with my forge fire and getting it up to the right size of fire ball. So far all it will do is heat 1/4 inch steel on a good day. I have had 1 1/2 inch steel bar forge welding temp in this thing so I'm baffled as to what I'm doing wrong. The only change that has been made is the addition of a hood and chiminy. Quick description of my set up. I have 4" square pipe tyure with a 2" square opening in the bottom of the fire pot. Fire pots about 6-7 inches deep and 12" by12" at the top. I have read everything on this site about fire building and have gone threw my books. I'm at a loss, so Give me all the help you guys got, I need it. Thanks Sam Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted July 13, 2012 Share Posted July 13, 2012 So what did the local smith say when they looked over your fire? For some things the Net is not the best source of information! Put your general location in your profile and you might get an invite to visit another shop to see how they are doing it. Otherwise we need to know all the details, types and size of coal, tuyere, blower, height of fuel stack, etc and usw---a picture will help Quote Link to comment Share on other sites More sharing options...
Glenn Posted July 13, 2012 Share Posted July 13, 2012 Do you have one air inlet from the blower etc. With a T system, any air outlet other than through the forge is not good. Check the down pipe, ash dump, to see that it is closed and not leaking air. If you have just a 90* elbow between the blower and the forge, check to see if the airway is open. I like a LOT of air going from the blower to the forge and find that for me a 2 inch twyere opening needs only one 3/8 inch bolt across the opening, and a 3 inch twyere needs only 2 each 3/8 bolts across the opening. Photos of your set up would be most helpful. Quote Link to comment Share on other sites More sharing options...
samw1 Posted July 14, 2012 Author Share Posted July 14, 2012 I live in new Boston il. I thought my location was saved but I guess not. I will try and get pics up tomorrow. Gleen I have an ash gate at the bottom that sits loose but have never had a problem until now. I use to forge outside until I moved, and got a garage that I converted into my shop. Quote Link to comment Share on other sites More sharing options...
Rich Hale Posted July 14, 2012 Share Posted July 14, 2012 Um,,,,,lets see if we can chase this down: Everything worked fine until you added a hood and chimney......Do you suppose that had something to do with the current problem? Can you move the forge outside without the hood and try it again? Is the vent piping of sufficient size for its task? Does the piping go vertically all the way throught the roof and extend far enough above to use prevailing winds or breezes to be on your side? Are there any trees buildings or parts of the roof that impede a natural air flow past the vent? Have you tried to preheat the sustem by building a class A fire in the forge first to get a draft started? A rolled up newspaper lit on one end and held up in the hood should do that and if all is well it will develop a strong updraft.When I do that in a wood stove in our two story house it makes a roaring sound right away and then the wood fire goes well. There are a lot of threads in this forum with lots of information that may help. But if you go through these steps you may solve it or not. If not you can tinker with it for a long time and maybe find the issue. Ir several problems. None of this will be better advice than Thomas' suggest to get someone knowledgeable to take a look. Quote Link to comment Share on other sites More sharing options...
samw1 Posted July 14, 2012 Author Share Posted July 14, 2012 Rich, It is straight up threw the roof and the draft works amazing. I followed all that everyone on here has taught me so far in design and execution. My dad keeps telling me to put a damper in and limit the draft on lighting the forge, the only reason I havent followed his advice is the challenge I face in installing a damper. The chiminy pipe is 10" dia and 1/4 inch thick. The hood is a 30 gal drum all chopped up in the right spots. I can't pull it out without a major overhaul and lots of destruction. I used what I could get ahold of for free and it left me in a somewhat permanent situation. Unfortunately it won't let me upload pics, I only have an IPhone to converse with you guys, my computer crashed and I'm without easy access to upload photos. I am really hoping to find someone who can walk me threw in person on where I am lacking, but I have looked threw the member database and wasent fruitfull on Someone close. Quote Link to comment Share on other sites More sharing options...
Rich Hale Posted July 14, 2012 Share Posted July 14, 2012 Sounds like your on the right track,,did you try a class a fire with a rolled up newspaper to preheat the flue? ,,,That kind of in a remote way does wot your Dad said, you have a lot of still air in the size of p;ipe and it just needs a good reason to begin to move,,kind of like me! Quote Link to comment Share on other sites More sharing options...
pkrankow Posted July 15, 2012 Share Posted July 15, 2012 You say it was used outside, you moved, then set it up inside. How long was the forge disused? Take the blower off, make sure it blows, sweep the tue, ash dump, etc and all to make sure no squirrels moved in.... Phil Quote Link to comment Share on other sites More sharing options...
Drewed Posted July 15, 2012 Share Posted July 15, 2012 Sounds like a lack of air problem to me. Chimney and flue shouldn't affect the fire that much, smoke yes but not fire. Check blower and tywere for obstruction/ leaks. Then again, you could have too much air and it's cooling the metal. Quote Link to comment Share on other sites More sharing options...
Glenn Posted July 15, 2012 Share Posted July 15, 2012 Time to start over. Check all air ways to be sure they are clean of debris and open. Check to see the blower is putting out good quantities of air. At the T portion of the twyere, make sure the connections are air tight, and the down tube where the ash collects is clean of ash, and capped or plugged at the bottom. (The ash tube can fill up and choke off air flow, and should be dumped or cleaned early and often.) Make sure the square inch area of the grate is sufficient to allow ample air to the forge. My forge has a single 3/8 in cross bar for a 2+ inch opening and 2 each 3/8 or 1/2 inch cross bars for a 3 inch opening. I can fuel this forge with coal dust and the grate works well when the coal starts to coke up a bit. If you have a free standing forge, outside forge with no chimney move on to the next paragraph. The hood and chimney should be clear of debris and 10 - 12 inches in diameter. It should open as close to the fire as possible so it CAN draw the smoke from the fire. Pre-heat the chimney by burning a couple of sheets of newspaper close to or in the chimney. This gets the draft going to draw the smoke from the fire. The chimney should be as straight as possible for the best results. Bends, elbows, and horizontal runs, reduce or can kill the draft. The hood opening should be approximately the same size as the cross sectional area of the chimney. You MUST have sufficient air coming into the room to match or exceed the air that is being sent up the chimney. Open a window or door open to supply this air. The chimney height is recommended to be 3-4 feet taller than any surrounding object within 10 feet of the chimney. This may need to be extended in height if trees, or other tall objects are near by, or if the natural air currents cause a problem. An open chimney is best. If you use a chimney cap, the opening between the bottom of the cap and the top of the chimney is recommended to be 3-4 times the cross sectional area of the chimney. Build a fire from paper, cardboard and sticks that would make a boy scout proud. Add some small pieces of wood and get a good bed of coals. Add coal a double hand full at a time until it catches fire and cokes up. Punch it down so there are no air pockets or caves. You should continue to add coal till you get a fire ball about the size of a melon or 4-6 inches in diameter or larger depending on the size of your work. To heat your metal, [ole the fire down to collapse any air pockets or caves, and insert it about 2/3 of the way up from the bottom of the fire ball. Add just enough air to achieve the heat you need for the size metal you are heating. This allows the fire to burn the oxygen from the air before it gets to your metal, and the metal then gets only the heat. This should get you started. Build a fire in the forge outside and be sure it meets your needs. Then add the chimney and observe the way the fire preforms. Move the whole thing inside and it should work the same, being sure to have incoming air into the room to meet or exceed what is being sent up the chimney. Photos of your set up will greatly improve your responses to your questions. Many times the response is generic in nature as we can not see the problem. Your set up is different from any other forge and chimney set up. You may have to play with it a bit, changing ONE item at a time to tweek it to your needs. Quote Link to comment Share on other sites More sharing options...
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