Small heating disk for project

[Muggs]

Hello All,

I'm looking for a small heating disk for a project that I'm quoting. Ideally I would want a 1/4" disk heated by 12Vdc and ranging in temp from ~30C to ~50C (86F to 122F).
Does anyone know of a source for something like that? I can find plenty of "gum-stick" sized ones but nothing like a disk that is that small.

TIA,
Muggs

[reboots]

Perhaps you can simply use a resistor in a favorable package. Johnson Dielectrics RWPB03W350R0TS is a 350-ohm wirewound resistor in a 0.320x0.300x0.102" axial package, which is a little larger than your 1/4" requirement. 350 ohms with a 68-ohm series resistance at 12V would dissipate 288mW through the package, approaching its power rating of 0.3W. Whether that's hot enough will depend on the rest of your project, and of course the temperature isn't regulated; you would need either closed-loop control or a predictable thermal gradient.

https://www.mouser.com/ProductDetail/Johanson-Dielectrics/RWPB03U100R0TS?qs=sGAEpiMZZMug%252BNZZT2EIM%252Bw093hgTVdcWe%252BgpNzjgG8%3D

That part is an expensive precision resistor, and Mouser shows only qty/4 in stock today. If you think you might need production quantities, and/or are ready to devise a mounting method, there are cheaper and more available wirewound SMT resistors, with higher power ratings, in smaller packages.

[coppercone2]

that would be best suited on a aluminum substrate PCB IMO with some heat transfer glue poured on top the resistors (the ones they use for flashlight LED). Chassis mount resistors would be better or ones with a thermal pad.

[NiHaoMike]

How about a steel washer and a simple induction heater circuit?

[Muggs]

Thank you all, I really appreciate your insights.