Whilst we had the utmost success with the Fat Boy in the beginning, as the Propane cannister emptied out it started to behave quite unusually.
Although it still worked perfectly fine when it was standing upright, when it was turned upside down the super-hot blue flame turned into an over-oxygenated yellow flame – which meant that it wasn’t blowtorching things properly anymore.
I did some research and found out that this is a common problem as the cylinders empty out, and that you actually need a regulated blowtorch nozzle.
After searching online, I found a suitable model – also sold at Bunnings – the TS3000T. It comes in a pack with a propane cannister, under the code TS3000, which cost about $68.
It’s much larger than the standard nozzle, but has the required regulator and another feature the old one didn’t have – automatic ignition via the trigger. I gave it a test run and yes, it burns upside down perfectly with my half empty propane cannister. Sweet!