-Blacksmith stuff

DIY coal forge plan (this is the basic, every coal forge is made up from this basic schem):

Gas forge (easier and cleaner, but doesn't top the 1000°C necessary to forge welding unless you DIY or buy the right burner, anyway you can forge and heat treath):

Video to get an idea:

Burners for gas forge (for advanced stuff)

Building a gas forge is really simple. You only must get refractory materials (kaowool, firebricks, refractory cement etc.)

Accessories for anvil (hardy tools, you insert 'em in the square):

More advancer RailRoad anvils:

MIT course about modern forging.