[Stoves] Inverted top lit updraught

[Crispin Pemberton-Pigott]

Dear Andrew 

You have answered one of my questions: can the temperature be raised by
preheating the combustion air. It is easier to do in a stove than in a torch
so that is one angle to be exploited.

Re melting steel with propane+oxygen. The torch cuts easily but only with
the special many-flames-nozzle adaptor and only because the fuel doing the
cutting is iron+O2. The flame alone without the compressed O2 coming through
the middle is able to melt steel - i.e. it can be used for gas welding steel
to steel with (for example) a coat hanger as the filler wire.

Regards
Crispin