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The following is a quick summery of the 55 Forge. More in depth design and discussion can be found on the site. The original 55 Forge was bottom blast. The fire shown is a little shallow, so if there is a question, just add more fuel. The tuyere was a piece of auto exhaust pipe with 1/4 inch holes to accept 1/4 inch round bar in a X pattern to form a grate. Lots of open room for air to move up and into the bottom of the fire. The next test modification was to put a brake drum into the 55 forge as a fire pot. You can see the cone shape to the ash and the rim of the fire pot. The bricks were added to give the fire more depth for the project at hand. Ash will build up to the top of the tuyere in the bottom blast in a fire or two. There is a T configuration below the bottom of the forge that is not shown. The T section is close to the bottom of the forge and the down pipe is 12 to 18 inches long (what ever you have on hand). Clinker is not really a problem due to the size of the tuyere. Just let the fire idle for a minute or two and the clinker will solid up and can be hooked out. Ash will at times fill the down pipe and need cleaned out. I have run this forge using coal dust or breeze. Once the fuel starts to coke ( a couple of minutes into the fire ) there is very little fuel that falls into the down pipe. The next modification was to make the 55 Forge a side blast forge. Just cut a slice in the side of the wall and add an air pipe. The depth of the slice was to the top of a house brick laid on its side. It was available. The fire shown is a little shallow, so if there is a question, just add more fuel. I like this design as it is so simple to build and works. That is an aluminum clothes dryer vent pipe being used to transfer air from the blower to the forge. With the side blast version the ash and any clinker builds up under the fire. On either 55 forge, the cut edges of the metal as they are sharp. You can roll them over, or cut a 2 inch piece of metal from the parent drum, fold it in half long ways, and place it over the cut edge of the metal pan. The 55 forge was developed so that any one in any third world country could have a forge with little or no cost. The forge runs on solid fuel, coal, coke, wood, charcoal, lumbar, pallets, etc. As has been stated many times before, Fuel does not make the fire hot, Air makes the fire hot. If there is a question about how hot, then add more fuel and more air. It can and has reached welding heat. It has also melted the metal if you do not pay attention to what your doing. ( Do not ask how I know this as I was not paying attention.) The 55 Forge is a great design that is simple and works. It is easily modified to adjust the size of the fire pot, the depth of the fire pot, different tuyere configurations, and the list goes on and on. Folks thought a brake drum was needed, so I tried both a brake drum and rotor. Each has advantages and disadvantages and in the end were not required. It simply adds a level of complexity to the system and overcomplicates simple. The fun part of the 55 Forge is make one, use it, modify it as you wish. When you finish there is another 55 Forge on the other end of the drum as a spare. The label on a drum is NOT accurate, it only means that is what the drum contained just before the label was applied. I found a empty drum at a auto repair shop. The label said 5W30 motor oil with a brand I immediately recognized. Somehow the top of the drum was hooved or domed a bit. When I removed the bung plug from the bung hole there was release of pressure and an overpowering aroma of gasoline and other very volatile materials. I ask the shop manager about the drum and he said "Oh that was the one they used for racing fuel last weekend." ALWAYS choose a drum that you can pronounce what it contained before you brought it home. NEVER use anything that throws off heat or sparks when you open a closed container or drum. If in doubt, have someone else cut the drum in half while you go get a burger and fries for the both of you for lunch. The 55 Forge is just a way to get you started quickly, so you can play in the fire while you research and plan on what your second forge design will look like.