Just a quick update: I have obtained an oxy-acetylene torch, bought a length of fat tube, found and drilled some scrap steel and cobbled together a large burner. On just propane, it puts out a large amount of heat, but with a scarily diffuse, large and unusable flame. I now need to try and hook up the oxygen pipe to the compressor and try again.
UPDATE TO UPDATE. Just hooked the torch up to the compressor and tried again: success! It has a nice, bright blue flame, totally controllable and, if the roar is anything to go by, very powerful. I need to tidy the burner up a bit, mainly because the jet is in at a slight angle and the flame is not central to the shroud, but otherwise, it is ready.
Once it is finalised, I shall post some pictures and, if possible a video of it in use.
Regards,
James.