I had a post about this on the old website, and never transferred it over to here.
Some time ago I bought a Scotch TL901 laminator with the intention of using it to transfer toner to PCBs for etching custom circuit boards at home.
It is really a simple machine inside, required a single resistor wired in with the thermistor to bring the heat up to the needed temp to transfer the toner.
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Essentially adding that resistor raises the set temperature so the rollers get hotter, which allows cleaner toner transfer.
Video: