When it came time to open up my box of 7018AC electrodes, I didn't want to just leave the box open, nor did I have the time to make a proper rod holding oven. So, I concocted a quick and dirty holding oven from some items I already had on hand: a five gallon metal paint can, a light bulb, some aluminum flashing, a grounded line cord, and a porcelain lamp holder.
The line cord is connected through the bucket with a proper strain relief, but it isn't visible in the pictures as it lives underneath a half inch of insulation covered by aluminum tape. Although it is rated to 105C, I still wanted to shield it a bit from IR and the ambient temperature of the unit.
The aluminum flashing serves to block the hot spot created by the lamp, and also serves as a convective circulator, helping to even out the temperature in the unit (there is about a one-inch gap at the bottom).
With a 60 watt light bulb, the rods achieve a uniform 220F temperature, which while less than the 250F recommended by Lincoln, is still better than letting them sit at the mercy of whatever the conditions inside my house are.
The outside is covered in standard house insulation, and small insulation "pillow" is placed over the lid to help insulate the unit. At 60 watts, the unit will cost me about $3.00 a month in electricity.
Eventually I may upgrade it with a thermistor/SCR controlled heating element from a toaster oven, but for now this works well enough.