If you are using stainless, which is the best choice for a pulse jet, you will not be able to weld it easily with oxy-acetylene. Bronze welding could work because it is well into red heat. You could also do a bit of research on Stellite. This is a hard surfacing alloy which, if my memory serves me correctly, can be applied using oxy-acetylene at around the same temperature as bronze welding but once it has been melted and resolidified the softening temperature to re-melt is higher than the first time. |