Here is my source of iron for this melt. It is an old cast iron fireplace insert. This thing slides into the fireplace opening in a home and the logs burn inside it. Of course it won't fit in the crucible in this form so I need to break it apart...
This believe it or not is the fireplace insert after about 15 minutes with a sledge hammer. Completely flattened and ready for the crucible. While it may seem unbelievable that the thing broke apart like this so easily, it's really nothing special. Cast iron is very brittle in thin sections and cracks almost like glass. So breaking it apart is so easy a caveman can do it.
Here is a crucible load of thin iron scraps. They are about 1/4" in thickness. I decided to start with something that should melt easily.
Lately I've been re-filling the fuel tank with used motor oil instead of used cooking oil. I can get a seemingly unlimited supply of this freely from auto repair shops as mentioned on the oilburners part 7 page. Used motor oil ignites easier and burns with a little more heat than used cooking oil. But used cooking oil is "carbon neutral" and a renewable resource. In fact check out my comparison list of used motor oil Vs. used cooking oil.
When melting iron gas welding goggles are very helpful. Since with an oil burner the furnace chamber is full of flames it is nearly impossible to see the crucible without these goggles.
Here is a look into the furnace with a gas welding lense over the camera lense (you can't see in without it) Notice how the level of the metal in the crucible has dropped due to melting.
Here are the tongs I made to lift the crucible out the furnace. I "slapped" them together in about an hour at 2:00AM the morning before I made this iron melt. The ones I made from a pair of plier-type nippers shown on the brass casting page have been discarded. Notice that the "gripping" section is "V" shaped. This design should allow these tongs to lift crucibles of several sizes. The crucible will just fit deeper or shallower into the V's depending on it's size.
Yep, that's hotter than aluminum alright. Notice my safety clothing... jeans and orange t-shirt. In my metalcasting booklets I mention wearing safety clothing for protection yet I don't. But I think all the authors mention that 'cause no one want to get sued! I plan to buy safety clothing (or at least start wearing gloves) but without it if I feel uncomfortable heat I know to move back. With a special safety outfit I may not feel the heat and thusly get over confident. This could lead to the outfit catching on fire (from being too close to the furnace) and in a panic a person could forget to "stop-drop-and-roll" and next thing you know you're running around the yard looking like the human torch from the Fantastic 4!
At last I have broken the "iron ceiling" and managed to get a controlled iron melt! Indeed this iron is not hot enough to be very useful for most castings but the point is that I put the pieces of technology together succesfully and now only have to improve the system. I'm pouring the metal with the liftout tongs but I plan to build a nice pouring shank soon.
Back in 2002 when I first put my waste oil burner experiments online a lot of people in the Yahoo! metalcasting forums were publicly against waste oil systems. I was once told that this is "third world" technology not worth the effort. I was told that the burners produced "dumb yellow flames" (yes that was the term used) and that I should stick with propane. Fortunetly I was determined and confident in my work. And I quickly realized that these people were uneducated in this field. Had I listened to them and the many "armchair experts" this iron casting and many of my future achievments would not be possible for me. So the lesson here is SCREW THOSE... uh, I mean... Don't give up on your goals!
Here is the resulting ingot. Nay... it is not a mere ingot! This artifact is the culmination of over 5 years worth of research and development, and indeed a substantial amount of money. This is the "iron stone" that will pave the pathway to a cornucopia of backyard metalcasting advancements! Let's move on to the next page.