Selecting appropriate torch tip

Hi Lisa

What am I doing wrong? My O2 pressure is set about 5-7# and my
propane is a small canister that I don't set pressure. Any ideas? 

Sounds like you have the same setup as I do. After I got your email,
I tried my number 3 tip. I was able to light it an keep it lit,
although it was a bit difficult. I don’t think that you are doing
anything wrong. The number 3 tip is just very small and hard to keep
lit. What works for me is to keep it very very small ie say a
millimetre or two long, and keep the flame bright by maximizing the
oxygen. My guess is that one of your regulators may be operating a
bit roughly and not keeping a steady pressure. Not a problem as long
as you can operate your # 4 tip I don’t believe that I have used my
#3 many times. I only use it to repair very fine chain. Number 4 is
probably the smallest you would really ever need. I typically use my
#5 and #7.

Regards
Milt Fischbein -
Calgary Alberta