Do I handle the torch differently when using alternate fuel gas for cutting?
Yes, adjusting the preheat flames is quite different when using alternate fuels. The preheat flames must be worked up in order to force a high volume of fuel gas out of the tip. Insufficient gas flow will result in starving the tip, causing the flame to burn slightly inside the tip, which In turn will cause the tip to over-heat. Forcing the fuel is accomplished by repetitiously opening the torch fuel valve followed by the oxygen valve to work up the flame. Once the flame has been adjusted to provide a strong gas flow, oxygen is added for the final time to produce a neutral flame. This is accomplished by adding additional oxygen to the flame until the preheat cones are reduced to their shortest point. Adding oxygen beyond that point will produce an undesirable oxidizing flame. Also, due to the slower burning rate of alternate fuels it requires the torch to be positioned further away from the steel when preheating. When using acetylene, the points of the preheat flames are typically posi
