Re: Soldering 402 chip R's

John Larkin wrote:

On Wed, 19 Sep 2007 13:21:28 -0700, Paul <energymover@xxxxxxxxx>
wrote:


On Sep 19, 1:08 pm, Spehro Pefhany <speffS...@xxxxxxxxxxxxxxxxxxxxxxx>
wrote:

On Wed, 19 Sep 2007 13:02:21 -0700, Paul <energymo...@xxxxxxxxx>
wrote:


Does anyone have any advice on soldering 402 size chip resistors to a
PCB? I thought perhaps some liquid solder that would slowly dry when
heat is applied from a heat gun.

I just use an iron. You need to actively hold them down or they'll get
sucked into the solder blob by surface tension. I tin one side, attach
the resistor then resolder both sides to make it pretty. A bit slow,
and you can expect to lose (as in never see again) some percentage of
the part.


Sounds like you're rather skillful. I can hardly see these buggers
with the naked eye. They're about the size of a grain of sand. So you
remove them from the paper, place it on the PCB, then place an iron
across the entire R? What percentage of R's will stick to the iron?



No.

Get an illuminated magnifier or some 2.5x granny glasses.


Granny glasses is a good one :-)


Small-tip soldering iron.


The Weller ETS tip is my favorite. Keep super clean, use sponge often.


Blob a little solder onto one pad.


With the emphasis on "a little". Kester 15mil no-clean still looks like a sewer pipe compared to 0402 but it's the smallest I could find that worked.


Place resistor with tweezers, and reheat that pad to solder one side.


I often use a tooth pick to hold them down.


Solder the other side.

Touch up as required.

Practice.


Or design with huge parts, like 0805's.


--
Regards, Joerg

http://www.analogconsultants.com
.

Relevant Pages

  • Re: Soldering 402 chip Rs
    ... I thought perhaps some liquid solder that would slowly dry when ... heat is applied from a heat gun. ... I just use an iron. ... remove them from the paper, place it on the PCB, then place an iron ...
    (sci.electronics.design)
  • Re: Soldering 402 chip Rs
    ... I thought perhaps some liquid solder that would slowly dry when ... heat is applied from a heat gun. ... I just use an iron. ...
    (sci.electronics.design)
  • Re: Soldering 402 chip Rs
    ... heat is applied from a heat gun. ... I just use an iron. ... sucked into the solder blob by surface tension. ... remove them from the paper, place it on the PCB, then place an iron ...
    (sci.electronics.design)
  • Re: Soldering 402 chip Rs
    ... heat is applied from a heat gun. ... I just use an iron. ... sucked into the solder blob by surface tension. ... remove them from the paper, place it on the PCB, then place an iron ...
    (sci.electronics.design)
  • Soldering 402 chip Rs
    ... PCB? ... I thought perhaps some liquid solder that would slowly dry when ... heat is applied from a heat gun. ...
    (sci.electronics.design)