john said:
I must have lived a sheltered life because onmy Antex soldering iron I
have always used a standard chisel tip.
Recently I saw a lot of cheap soldering irons in the stores with a
conical tip. I can't think I'd ever want to use that shape but someone
must be doing so. What use does a concial tip have for
electrical/electronic work?
I think that to some extent, it's a case of what you get used to. The
'standard' 700 degree bit that most people use on the old Weller TCP
Magnastat irons - and bear in mind that for many years these were the
workhorse iron of the electronics industry, and are still to be found in
many workshops - is conical. I have always found that a conical tip is much
better on high density boards, as a flat or chisel tip can easily heat two
joints at once if you don't position it carefully. If you are soldering
under magnification, as is sometimes required with even fairly 'ordinary'
boards, I find that it is easier to see what you are doing, with a small
conical tip.
I don't find that I have any problem getting enough heat into joints with
this type of tip. If your iron is set for the right temperature for the
solder being used, it won't be a problem. If any joint won't flow
satisfactorily, then the iron that you're using is either not powerful
enough, or a conical tip simply isn't appropriate for that particular type
of joint. Those of us professionally involved in bench soldering, usually
keep two or even three irons, plus desoldering equipment, at the ready, and
just reach for the 'right' one for the job, without thinking about it.
Obviously, there's a lot of generalisations there, and for hobbyist or
occasional use, the 'traditional' or standard Antex-style chisel bit, is
probably the most versatile general-use type. One downside of conical tips,
is that the plating tends to fail fairly quickly, so they don't last as long
as chisel tips. We had quite a debate about this on here a few months back,
and we all pretty much agreed that the conical Weller TCP tips used to last
a lot longer than they do now. One interesting document came up in that
debate, which explained about the dreaded lead-free solder leaching iron
from the tip plating and accelerating wear which, when coupled with the more
aggressive fluxes used in this stuff, leads to much shorter tip life.
Arfa