Best professional soldering iron??

"db" wrote in message
.. .
So if you run a big iron for any length of time, and the tip begins to
exceed the melting temperature of lead came, how do you keep from melting
the lead came when you solder? I use a controller, actually rest the tip
on
the lead for a couple seconds to get the solder to flow. I obviously
couldn't do that without the controller. Do you actually never touch the
iron tip to the lead directly?

you move, and quickly. I solder lead came, with large and small irons,
depending on the size of the came and what solders easiest, they are all
quick. I do not use a controller, every so often I do clean the tip off,
its gets hotter faster than I can solder, and I am not slow. the cleaning
cools it briefly, but the more joints you solder and the quicker you do it
lets the heat be used at the same rate the iron heats. Optimal performance,
takes a bit of practice, but the controller is no longer a hindrance.

"db" wrote in message
.. .
So if you run a big iron for any length of time, and the tip begins to
exceed the melting temperature of lead came, how do you keep from melting
the lead came when you solder? I use a controller, actually rest the tip
on
the lead for a couple seconds to get the solder to flow. I obviously
couldn't do that without the controller. Do you actually never touch the
iron tip to the lead directly?

It seems to me that if you are actually leaving the iron tip on the lead
came for a couple of seconds (actual time), you are probably working with
an iron that is too cool. Lead came is fairly thin in cross-section, and
pretty easy to melt with an iron.

Think it through. It's physics, not witchcraft.

Lead came melts (depending on the alloy) at somewhere around 650F. Solder
melts (depending on the alloy) at about 530F. If your iron isn't
"instantly" liquifying the solder, it is too cool. You want the lead to
heat up to some temperature that will cause the solder to adhere to it, but
not hot enough to instantly melt the lead. You have about a 100-120F range
that you can work in. (Between the solder melt point and the lead melt point
is that 100-120F range.) If you have to wait even a nanosecond for your
solder to flow when applied to the iron tip, you are too cool. If the lead
came melts as soon as you touch the iron to it, you are too hot. What you
are trying to do is to have a localized molten pool of solder flowing over
some warmed lead that is not yet at the melt point, and then remove the heat
so the solder will crystalize around the warmed lead, forming a solid
mechanical joint. You are adding a new metal to the joint, not melting and
re-fusing the lead.

Everybody probably has a different technique; here's how I do a new lead
joint. After fluxing, I will put the tip of the solder wire onto the joint
and lay the flat part of the iron tip on top of the solder. As soon as the
solder melts, I will leave the iron there for "one-alligator" and lift the
tip straight up. The surface tension of the molten solder causes the joint
to "bead up" or make a little mound where the lead intersects. If the joint
isn't visually what I want, I might go back and add some solder. The trick
is to lift the iron straight up from the joint, not drag it off to the
side. Makes a nice, neat little joint that way. It is ALL about practice
and rythmn.

I prefer an internally controlled iron with a tip temp of 700F, so that I
know exactly what to expect when I solder the first, tenth, or hundredth
joint in a window. It's all in what you get used to and what meets your
needs for the project. Don't get caught up in the rhetoric about speed and
tip temperatures and phoney blustering. Having a 1100F tip is overkill and
wattage is only important in heat up (and recovery) time. A 30w iron will
get every bit as hot as at 300w one, it just takes longer to get there.

Think of this whole thing in reverse. An ice cube laying on a counter at
room temperature is 32F. So is a 25lb block of ice. It's just a difference
in mass, and how long it will take the cube vs.block to melt into water.
It took longer to freeze the block of ice than it did the cube, and the
block of ice will cool your 12 pack when the one ice cube won't. It's all
about thermal mass...

Ice is ice, and molten solder is molten solder. Once solder melts, it
does no good to continue heating it. At some point the molten metal would
begin to vaporize (like boiling water)...and you'd be in serious problems
with lead poisoning there. Solder at 530F works just as well as solder at
1100F.

"db" wrote in message
.. .
So if you run a big iron for any length of time, and the tip begins to
exceed the melting temperature of lead came, how do you keep from melting
the lead came when you solder? I use a controller, actually rest the tip
on
the lead for a couple seconds to get the solder to flow. I obviously
couldn't do that without the controller. Do you actually never touch the
iron tip to the lead directly?


All the techno-babble aside, it just takes practice. Sometimes I'll go to
an 80 watt iron for trickier lead. I solder fast but I am getting older,
and I like a bigger safety net these days. Alot of flux will also tend to
cool down the tip, and yes I touch the lead with the tip. The worst thing
that ever happened to me was doing a little repair to a 100 year old lead
filigree panel lamp. Melted a section of an intricate design by accident. It
took me a long long time to recreate the missing section.

--

JK Sinrod
www.sinrodstudios.com
www.MyConeyIslandMemories.com