After the furnace had been allowed to cure for a week, I removed the inner form and started a small wood fire inside to drive off most of the steam.
Meanwhile, I removed the form for the vent hole of the lid, and then stuck the lid in the oven at 250 degrees for about 3 hours to drive off moisture.
Voila! After removing the nice and toasty lid from the oven, it was noticeably firmer (firm enough to pick up).
The furnace had been burning a small fire the whole time. Once the lid came out of the oven, I stoked up the fire again (it is mostly coals in this picture) and placed the lid on top.
Notice how nicely it fits on top and completes the furnace.
Ramping up the heat by adding a small computer fan for forced air.
All the steam is gone by this point.
It has gotten hot enough to start the oil burner up. Notice the CO2 tank pressurizing the tank with around 1 psi - enough to force the oil out in a smooth stream.
There we go!!!! Now that's what I call a flame!
Ahhhhhh, what a beautiful sight!
It has reached the point where I need to use a welding mask to look inside or else I'm blinded for a few seconds. Notice the lens flare it's giving the camera.
Now THAT is hot.
This thing is really, really hot - I'm estimating around 2000-2500 degrees inside... which should be enough to vitrify the refractory.
The excitement is over, for now. Brick up the furnace and let it cool overnight.