Thanks for the info MangoAve.
The heat removes any water so it is not trapped in when the hairspray seals the surface from oxygen entering the relic. It is a fast way of cleaning and sealing your relic. The other option is time consuming but lasts longer. Removal of chlorides is the ultimate goal, but realistically, we usually abrade the iron with a wire brush an remove the water and seal it.
Finding relics is in my blood
GPX 5000, CTX 3030, E Trac, Vista Gold