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This is where I keep pictures of the F1 furnace, from construction through the final melt when it happens. Have a look around and enjoy the pictures. Any questions, you can contact me at "derek" at n e r d u l a t o r . net (remove the spacing, quotes, etc)

Construction Pictures - 10/15/07

These are a few pictures taken during the construction of the furnace. They show the general method of assembly, but don't detail too much of the plans or instructions. There is a full set of plans here if you are considering building one.

First Ignition - 10/16/07

These pictures were taken during the curing of the furnace. A wood fire was built in the furnace to drive the moisture out of the furnace walls, and cure it. This may not be necessary, but I did it anyway to make sure the moisture was out.

The First Oil Burn - 10/18/07

Assorted pictures after testing the F1 burner and controls, to achieve a self-sustaining waste oil flame. The goal was to test the burner and evaluate the controls, but I put a piece of aluminum in the furnace just to get a preview of the flame temperatures I was getting. I don't have the thermocouple installed yet at this point, so there isn't any temperature data available. I'll plan to put it in this weekend, and start posting thermal charts along with the pictures. The tests were successful, and the aluminum bar melted some but didn't puddle. These pictures are after the burn is complete, I didn't have my camera during the burn (poor planning!), and didn't feel comfortable leaving the furnace running to go get it. The conclusion from this test is that much finer fuel controls are needed, and the 3/8" line is definitely way overkill for the fuel pump used. The fuel control I was using here is a small piece of plywood with two screws in it, clamping a metal bar onto the fuel hose to create a restriction. The fuel flow was unstable, and the furnace either ran too lean (smallish flame, low heat output, high exhaust wastes), or too rich (oily smoke, leaking liquid oil onto the sand pile). A needle-valve type control is definitely necessary, and I think I will reduce the fuel line to 5/16", and further to 1/4" for the needle valve control. It may not be a bad idea to make a stainless steel "injection" nozzle that will fit inside the fuel intake port, and provide a more consistent flow. Despite all the problems, the furnace self-sustained on the used motor oil, and even melted the piece of aluminum I put in there.

The YMD-F1 EOL - 10/25/07

The YMD-F1 Furnace is now end-of-life. It achieved a total of three melts, which isn't very impressive, but it served the purpose of getting my feet wet, and preliminary testing just fine. I blame the failure on the low fracture strength of the refractory. The furnace didn't really fail on it's own, I kind of picked at it a little to see if it was durable or not. Turns out it's not. I think there was too much perlite in the mix, resulting in a low tensile strength after the perlite burned out of the refractory. Perlite "fuses" at a pretty low temperature. The hairline cracks that had formed earlier expanded to the point at which I could see the flame inside, and then the furnace body eventually fell apart. I attempted patching it, but it appeared the perlite had fused out, and the resulting structure was far too brittle to handle without further breaking it. I have a feeling it will be re-incarnated, rising from it's ashes like the mythical phoenix.