I have used one to remove cable stop, which is sort of reverse brazing....plenty of heat.
does use a lot of Oxy tanks..... we are talkikng minutes not tens of minutes.
it is a handy thing and good for what it is
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Life is too short not to ride the best bike you have, as much as you can
(looking for Torpado Super light frame/fork or for Raleigh International frame fork 58cm)