This is the conundrum, fitting 3/4 of a Q8 into an S2 sized package.
“Ye cannae change the laws of physics”.
“I’ve got to have 30 minutes” …
Perhaps filling the head with a phase change material could keep it going on turbo for more than a minute before step down. Much much better than simply relying on thermal mass.
Quick estimate: Paraffin wax, heat of fusion 250 kJ/kg.
Find a way to fit say 25g, that could soak up 6.25 kJ, lets say on turbo its pulling 4A from 3.7V = 14.8 W ignoring the light coming out of the front.
So the wax could maintain the head at a safe level for 422 seconds = 7 minutes of full turbo before step down became necessary. Of course there would then have to be a lengthy cooling off period before giving it another full blast. Meanwhile it would make a nice handwarmer on cold days.
Another wacky idea: monitor the LED forward voltage shift with temperature to get a precise reading of the LED junction temperature rise. Saves the need for an MCPCB sensor and measures it where it really matters. Use high melting point solder too, in case of accidents.
PS: if there are going to be FW3Ti and FW3Cu in future, the thermal control may need some re-tuning to cope with the very different thermal properties in case A (particularly for Ti), hopefully the “universal” system will adapt when in 7135 mode.
PPS: I think there is still a place for “hotwires” in bright torches, at least the incandescent bulb chucks it’s waste heat out of the front instead of into an MCPCB, and of course the CRI is perfect Make a handy fire-starter in emergencies too.