My Hartman Electric Furnace

[rgsparber]

Back around 2002, Dan Hartman masterfully updated the 1984 electric furnace designed by David Gingery. In 2008, I stood on Dan's shoulders and attempted to improve on his design. Here is the result which has served me well.

If you are interested, please see

https://rick.sparber.org/modified%20...%20furnace.pdf


Your comments are welcome. All of us are smarter than any one of us.


Thanks,

Rick

[NortonDommi]

Thanks Rick,
I love your PDFs. Have you ever looked a foamed cement? One day if people ever stop bothering me I need to build a furnace and I have seen a few people using foamed cement sealed with Waterglass as the insulator with very good results. I like the fact that it is easy to work with and castable.
Here is a link to a foam generator that works well: http://pelagic.wavyhill.xsmail.com/

[rgsparber]

Thanks Rick,
I love your PDFs. Have you ever looked a foamed cement? One day if people ever stop bothering me I need to build a furnace and I have seen a few people using foamed cement sealed with Waterglass as the insulator with very good results. I like the fact that it is easy to work with and castable.
Here is a link to a foam generator that works well: http://pelagic.wavyhill.xsmail.com/

I don't have any background in cement but the paper is certainly interesting. I couldn't find a date so wonder when it was written and how have samples fared over time.

I know that mixing high temperature cement and perlite is a common procedure when making furnaces. It would have a similar outcome.

Thanks,

Rick

[hemmjo]

...Have you ever looked a foamed cement? snip... http://pelagic.wavyhill.xsmail.com/

I have looked at foamed cement for use in raised bed planters. It my research says it is not very durable. I also know that Portland cement is not very heat resistant at the temperatures you may want in a furnace. At 1500˚F portland begins dehydrate. Hydration is the process that causes the cement solidify and to bind to the materials in concrete. Any prolonged temperatures about 1500˚ will destroy the cement.

I have this link bookmarked for when I get around to building a foundry furnace.

I ask have an old ceramic kiln, that I recovered from the trash, stored alone with my other "will get to it someday" stuff. It has lots of that soft fire brick heating elements and a nice stainless steel exterior that will be easy to reconfigure to a crucible furnace.

John

[bruce.desertrat]

Thanks Rick,
I love your PDFs. Have you ever looked a foamed cement? One day if people ever stop bothering me I need to build a furnace and I have seen a few people using foamed cement sealed with Waterglass as the insulator with very good results. I like the fact that it is easy to work with and castable.
Here is a link to a foam generator that works well: http://pelagic.wavyhill.xsmail.com/

This sounds a lot like the RAAC concrete (currently starring in a huge scandal in Britain) https://en.wikipedia.org/wiki/Reinfo...rated_concrete