I am building a 1000W microwave kiln for glass jewelry. The internal capacity needs to be around 5 litres. What internal dimensions of the cavity should I avoid, or strive for, to ensure even heating. Where should I locate the feedpoint, and. Would a magnetron feeding into such a small space be subject to an excessive load?

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    $\begingroup$ so, while microwave kilns use RF, they're not radios, and although it all boils down to Maxwell's equations, it's not a question about general radio technology or theory. This is engineering a specific heating device, so maybe ask this over at electronics.stackexchange.com . $\endgroup$ Jul 26 '19 at 8:36
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    $\begingroup$ (also, seriously, a 1000W microwave oven can, without being obvious, lead to permanent or even lethal damage (Ok, death is permanent, too) if built incorrectly, and you can only verify it's built correctly by using expensive microwave measurement equipment. This might be one of the rare cases where "if you have to ask, this project's a bit too dangerous for you" applies. There's microwave weapons with lower power.) $\endgroup$ Jul 26 '19 at 8:44
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    $\begingroup$ @RJohnson The problem lies in how easy it is to accidentally "weaponize" that Panasonic. Defeat one interlock, and it's very dangerous -- and I can see doing that accidentally, if you're poking around in the works. $\endgroup$
    – Zeiss Ikon
    Jul 26 '19 at 11:18
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    $\begingroup$ "simply trying to downsize" but that involves a complete re-engineering of a microwave resonator cell. That's the majority of the RF design involved. "I'm just trying to replace the horses in front of a carriage with an electric motor" would be an analogy that comes to my mind. $\endgroup$ Jul 26 '19 at 14:51
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    $\begingroup$ Why do you want to make the cavity smaller? Size makes very little difference, all the energy is absorbed by the food or other load. Also how will you seal the smaller cavity? Kitchen microwaves have a cunning quarter wave choke that seals the oven without electrical contact (which would get dirty and rust etc.) $\endgroup$
    – tomnexus
    Jul 26 '19 at 17:36

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