Found Dreaming

My furnace lids are bare ceramic wool, currently held in place with ceramic disks laced to the metal framework with Inconel wire. I run oil burners and really pour in the heat. It's pretty rough on that wire over time. I'm wondering what wire may be a better choice. I looked at titanium, which has a higher melting point, but it seems that it would oxidise too badly in the heat, the same as steel. (There is platinum and palladium of course, and while I'm at it I could buy a new Rolls Royce as well). Is Kanthal a better choice than Inconel? Is there some sort of ceramic rope made?

Richard

here you can get ceramic fiber board, in mexico I don't know. you going to have to do some research on the wire thing.

How'bout stainless TIG rod that's like an 1/8th inch thick?

it will burn out.

Yes, oxidation is the problem with steel, or stainless, or titanium. The wires that don't oxidise at high heat that I know about: Inconel, Kanthal, thermocouple wire, all melt at around 2600 or 2700 F. I run my furnace over that. Granted some of the heat is conducted away by the wire out to the cooler regions, so the wire never gets to the temperature of the innermost heart of the furnace, but the wire still suffers. Oh, for some 3000 degree wire.

Richard

I think they make some ceramic buttons that have a stem that goes into the blanket. The wire attached to the stem and is protected from the heat.

The ones I have found are good to about 2500 F. I made some from Mizzou. Two of them have held up. Two broke. The stems broke off. Not in use, but in installation. Mizzou is not exactly designed for small, high strength parts. I think I will make a few more. I will be firing up in a day or so and will stick them in the furnace for a cure. The two that did not break are still doing fine.

Richard