Stacy E. Apelt - Bladesmith
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There seems to be so many people wanting a forge but confused on the cost and difficulty of making one. While large forges can be complex, a simple beginner forge is simple to build and low cost. Lets get started.
The forge has there parts - yes, only three! The shell, the refractory, and the burner.
The Shell-
Any tube of material that wont melt or burn will work. Normally it is a metal tube or piece of large pipe. Some low cost and readily available ( often for free) things can be found, but the best two are:
Pipe - By far the best choice - A 12" piece of 6-8" pipe. Most scarp yards, and many machine shops have it laying around. A plumbing company may give you a scrap piece.
A suitable shell can be a section from a surplus large gas tank (O2,nitrogen, helium, etc.).
The refractory:
There is no point in scrounging here - one linear foot of 24"wide inswool is $9.50. Five pounds of satanite is $14. High Temp Tools and Refractory sells all forge supplies and much more.
The Burner:
You can build a venture burner, but there are so many little quirks that the best choice is to buy one. Atlas Forge sells a great 30K BTU burner with regulator and hose that connects to a 20# BBQ propane tank. $60.
A few 1/4" bolts, a 3"X1.25" pipe nipple ( or similar length of pipe), some firebricks, etc. will finish the job. $100 will make a first class forge.
Start with the shell. Lets assume you have a 12" long piece of 8" pipe. Drill/cut a hole that matches the inside of the 3"X1.25" pipe nipple. The hole should be placed 4" from the back end of the forge shell. Grind a curve on the end of the nipple that will make it sit flush with the shell. It should be at a slight forward angle, and at a tangent to the chamber when the refractory is installed. This will make the flames flow around the walls of the chamber. Once you have all that figured out ( tip- draw it on paper full size first), weld the nipple on the shell. Before you weld it on, drill two sets of three holes 120 degrees apart. Drill them about 3/4" from each end of the nipple, and tap them for 1/4" bolts. These will lock the burner in place later on. Weld on some legs so it sits about 4" off the table. Rail road spikes make great legs.This completes the simple shell of a tube forge.
Next, we line the shell with the inswool. Roll a sheet of paper up and measure the inside circumference of the forge shell. Cut the Inswool to that length. Roll it up and slip inside, lining the shell. Adjust as needed so it makes a nice fitting lining. Use a thin knife to punch a hole where the burner will come in. Slide the wool out and make a 2" circle where the hole is punched. Put it back and align the hole.
Now we mix some of the satanite with water to a fairly thick mix that is about the consistency of yogurt or sour cream. Use a rubber gloved hand and a paint stirrer to spread an even layer over the wool..... about 1/4" thick is good. You wnt it fauirly smooth, but don't get crazy. Shape some of the satanite along the burner hole so it makes a "flared" opening from the burner tube to the chamber. Let dry and build this "flare" up in layers as needed. Let the refractory dry for a few days, and fire it with the burner in place and running very low. Just run a minute, turn off, let sit, run a little longer, turn off, let sit, etc. The idea is to slowly dry and cure the refractory. Once the lining starts to get well cured, give more heat and then run for 5-10 minutes. This will cure the satanite. At any point if cracks appear, let things cool off, patch with slightly thinned satanite mix, let dry a day, and cure again.
You now have a simple tube forge that will get hot enough to forge and work for simple HT.
Improvements could be a coating of ITC-100, and stacking firebricks at the ends to make adjustable ports.
You will have to play with the burner position, moving it in and out to find the sweet spot where it runs low and high best.
www.hightemptools.com is where you find all the supplies and also great FAQs about using the materials and making a forge.
Atlas Forge is here on Bladeforiums, and sells his burners ( and completed forges) in The Exchange.
The forge has there parts - yes, only three! The shell, the refractory, and the burner.
The Shell-
Any tube of material that wont melt or burn will work. Normally it is a metal tube or piece of large pipe. Some low cost and readily available ( often for free) things can be found, but the best two are:
Pipe - By far the best choice - A 12" piece of 6-8" pipe. Most scarp yards, and many machine shops have it laying around. A plumbing company may give you a scrap piece.
A suitable shell can be a section from a surplus large gas tank (O2,nitrogen, helium, etc.).
The refractory:
There is no point in scrounging here - one linear foot of 24"wide inswool is $9.50. Five pounds of satanite is $14. High Temp Tools and Refractory sells all forge supplies and much more.
The Burner:
You can build a venture burner, but there are so many little quirks that the best choice is to buy one. Atlas Forge sells a great 30K BTU burner with regulator and hose that connects to a 20# BBQ propane tank. $60.
A few 1/4" bolts, a 3"X1.25" pipe nipple ( or similar length of pipe), some firebricks, etc. will finish the job. $100 will make a first class forge.
Start with the shell. Lets assume you have a 12" long piece of 8" pipe. Drill/cut a hole that matches the inside of the 3"X1.25" pipe nipple. The hole should be placed 4" from the back end of the forge shell. Grind a curve on the end of the nipple that will make it sit flush with the shell. It should be at a slight forward angle, and at a tangent to the chamber when the refractory is installed. This will make the flames flow around the walls of the chamber. Once you have all that figured out ( tip- draw it on paper full size first), weld the nipple on the shell. Before you weld it on, drill two sets of three holes 120 degrees apart. Drill them about 3/4" from each end of the nipple, and tap them for 1/4" bolts. These will lock the burner in place later on. Weld on some legs so it sits about 4" off the table. Rail road spikes make great legs.This completes the simple shell of a tube forge.
Next, we line the shell with the inswool. Roll a sheet of paper up and measure the inside circumference of the forge shell. Cut the Inswool to that length. Roll it up and slip inside, lining the shell. Adjust as needed so it makes a nice fitting lining. Use a thin knife to punch a hole where the burner will come in. Slide the wool out and make a 2" circle where the hole is punched. Put it back and align the hole.
Now we mix some of the satanite with water to a fairly thick mix that is about the consistency of yogurt or sour cream. Use a rubber gloved hand and a paint stirrer to spread an even layer over the wool..... about 1/4" thick is good. You wnt it fauirly smooth, but don't get crazy. Shape some of the satanite along the burner hole so it makes a "flared" opening from the burner tube to the chamber. Let dry and build this "flare" up in layers as needed. Let the refractory dry for a few days, and fire it with the burner in place and running very low. Just run a minute, turn off, let sit, run a little longer, turn off, let sit, etc. The idea is to slowly dry and cure the refractory. Once the lining starts to get well cured, give more heat and then run for 5-10 minutes. This will cure the satanite. At any point if cracks appear, let things cool off, patch with slightly thinned satanite mix, let dry a day, and cure again.
You now have a simple tube forge that will get hot enough to forge and work for simple HT.
Improvements could be a coating of ITC-100, and stacking firebricks at the ends to make adjustable ports.
You will have to play with the burner position, moving it in and out to find the sweet spot where it runs low and high best.
www.hightemptools.com is where you find all the supplies and also great FAQs about using the materials and making a forge.
Atlas Forge is here on Bladeforiums, and sells his burners ( and completed forges) in The Exchange.
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No regrets.