Super small AC bed heater, how to control it?

I have found an interesting very small bed heater, one that is about 10cm in diameter. It is AC powered and can hit nearly 100 C.
Got your attention?
It is a desk-top coffee cup warmer.

I was looking for something to heat my micro-Kossel bed while also looking for a 15cm metal disk to use for a bed. I currently use a 5" (13cm) acrylic 1/4" thick disk for a bed. I found a mug heater in my desk junk box, and thought, huh, if this hits 60C then I am good. I taped the thermocouple from my DVM on the plate and turned it on. In a couple of minutes it hit 97C! This plate is metal, pretty smooth (about as good as most of the heated beds I've seen) and a diameter that I might be able to just use as the bed, if a little small. Acrylic has a melting point of 160C, it goes "glass" at about 105C, so heating it to 60-100C is a bad idea, so maybe just using the mug heater hotplate as the bed might be the better path forward. Regardless...
Jackpot!
So.
I have heard of others that use AC bed heaters and so I know that there is something we can connect to our printer boards to do this. Looking through Marlin code it seems like the bed is just "bang-bang" controlled, not PWM'd since it has such a high thermal mass. It would seem ideal to connect a triac circuit to the bed heater output to control an AC bed heater. I know they are used, what are they called?

They don't call us "hackers" for nothing!

Thanks,
DLC

Edited 1 time(s). Last edit at 11/16/2017 12:26PM by dlc60.

Use an SSR- it won't need a heatsink. Connect the SSR input to the controller, get a 100k thermistor and attach it to the heater using high temperature silicone. Never use bang-bang control for the bed heater. Use PID control- it's already baked into your firmware- all you have to do is turn it on.

Here's how I wired the electronics in UMMD, including a line powered heater:

[drmrehorst.blogspot.com]

Edited 1 time(s). Last edit at 11/16/2017 12:33PM by the_digital_dentist.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

I use a very cheap SSR for that. 400W 220V AC silicon heater
[nl.aliexpress.com]

Edited 1 time(s). Last edit at 11/16/2017 01:44PM by amigob.

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P3steel DXL, with Due/RADDS/Raps128 dual Wade's extruder

Just to say make sure it is a DC-AC SSR as they come in several flavours - DC-DC, AC-AC, DC-AC.
Also check the voltages.