On 30 Jan 2006 07:28:21 -0800, jim rozen wrote:

In article , Boris Mohar says...

Yes. Weller tips cycle the mechanical switch in the handle. Metcal tips use
curie point to continuously affect the amount of absorbed RF energy.

The weller tips also use the curie point, but as you say to
affect the switch in the handle.

I work with a *lot* of MOS and otherwise static sensitive devices,
and I've never had one of the weller irons like that cause a problem.
In fact they're my preferred iron, the variable temp weller ones
just don't last more than a year, and I don't like the 'feel'
of the metcal ones.

The handle's just not 'right.'

Jim

You need tiny delicate hands to solder 0201 resistors
Here is a trick that increases the life of the Weller iron switch. Solder a
1N400X diode across the switch terminals. The iron will not cool down as
rapidly and, switch will not will not cycle as frequently and it will be
switching less current. The transformer in the one that I modified was beefy
enough to handle the DC component caused by the half wave rectifier without
overheating.

--

Boris Mohar