Light bulb kilns are used primarily to dry parts like rungs to a super dry state, about 4%. This is a key component of making a strong joint. Because chairmakers often use air dried wood, this kiln can also be used to get the moisture content of parts like front legs and arms down to a usable percentage, usually about 8%. And it can even be used to dry slats after steam bending.
This kiln is based on the one I’ve used in my shop for many years. I’ve customized the design for people building a few chairs in their home shop by making it smaller and easier to build. For folks building Boggs chairs it can hold enough parts for 2 chairs.
Light bulb kilns were traditionally heated by 100 watt incandescent light bulbs. These have gotten hard to find. But there’s an excellent alternative — 100 watt ceramic heat emitters that are typically used to heat reptile terrariums. They screw into the light socket just like a light bulb and produce an equivalent amount of heat.
 
Plans by: Jeff Lefkowitz