while glow ignitors make combustion far easier, it is actually possible to start your glow engine without one. i know a guy up at the flying field that i belong to who one day was having trouble starting his engine. he got it to start once after much difficulty, he flew it, shut it off, and he gave up trying to start it again. he figured his glow ignitor battery must be low so he opened it up to put it on the charger and noticed there was no battery inside. he had forgot to take it off the charger at home and put it back in the ignitor. also, the filament is not just platinum. it is a platinum irridium alloy. two stroke lpugs have more irridium in the alloy than four stroke plugs do because platinum retains heat better. if there was a pure platinum brand and you put it in a two stroke, it would preignite every single stroke.