Normal forges can be used to make Dwarven armor (and weapons), but first you need the Dwarven Smithing Perk. This is also true of most other types of armor. Dwarven Smithing can be acquired at Smithing level 30.
Crafting Dwarven Equipment required Dwarven Metal Ingots which can be smelted from various pieces of Dwemer scrap metal. The breakdown for these pieces and how many ingots they produce is:
- Bent Dwemer Scrap Metal - 3 ingots
- Large Decorative Dwemer Strut - 2 ingots
- Large Dwemer Plate Metal - 3 ingots
- Large Dwemer Strut - 3 ingots
- Small Dwemer Plate Metal - 3 ingots
- Solid Dwemer Metal - 5 ingots
These items (along with ingots themselves) can be found lying around in the numerous Dwemer ruins and/or by looting Dwemer Constructs such as spiders and centurions.