>
> Hot plates keep getting hotter and hotter. I found that I ∗can't∗ use
> the hotplate for a second board unless I let it cool completely first,
> else the board burns (charred epoxy!).
>
You could attach a thermistor to the hot plate and build a simple temperature control circuit to keep the temperature FAR more stable than the controls, if any, that are built in.
I've never used a hot plate anyway though, I just transfer, soak, clean, etch, optionally tin with the liquid stuff, then solder the parts.