Re: Soldering irons [was Re: gEDA-user: Free Dog meetings at MIT starting this September!]

[sdb@cloud9.net (Stuart Brorson)]

My experience with Metcals is much better than with Wellers.  They
keep the heat at the tip better, and therefore deliver heat to the
part to be soldered more readily.  The reason -- as I understand it --
is twofold:  

1.  Metcals put a sensing element right at the tip of the iron to
measure the tip temperature.   Then they feedback on the tip temp to
control the current into the heaters.  This means that when you touch
a metal part with the iron's tip, the heat sucked away by the metal
part is immediately replenished by the iron, which pumps
current into the tip under command of the feedback circuit.   Wellers
don't have this feature.

2.  The heating element in a Metcal is right up at the tip of the
iron.  In a Weller, the heat slug is a slug which is heated from
further down the iron.  Therefore, the response of the Metcal's tip is
faster; it heats up faster, and the heat at the tip is replenished
faster if it is depleted.

Also, Metcal provides a variety of tips for their irons, including
nice, narrow ones for fine pitch work.  I don't recall Weller selling
really fine-pitch tips for their irons.

Please remember that this is my understanding of what's going on in a
Metcal gained by lab heresay; I might always be confused about some
detail or another . . . . 

Stuart



> 
> On Monday 23 August 2004 07:24 pm, Stuart Brorson wrote:
> > I'll lend my voice to the chorus of those who endorse Metcal soldering
> > irons for SMT work.  Metcal rulez, Weller droolz, IMHO.  Buy a Metcal
> 
> Why do you have this opinion?
> 
> --
> Samuel A. Falvo II
> 
>