[hpsdr] Atlas, How do I hand solder this thing?

[Steven Bible]

The two iron or twezzers method is for all the two lead parts (caps,
resistors, diodes, etc.).  The idea is that the part will position itself
using surface tension when the solder is in its liquid state.  Very handy.

For multi-leaded parts, the technique depends on the part.

For dual inline parts (SOIC, SSOP, TSSOP, etc.) keep all the pads clean and
free of solder.  Pick one corner pad and apply a tiny bit of solder.  Then
with tweezers, position the package over the pads, align, then solder.  Melt
the solder and repostion as necessary until the part is aligned.  Then
solder the opposite corner lead.  Now the part should be in position,
aligned, and you can solder the remaining pins.

For very fine pitch quad leaded parts (CPLD or FPGA), keep all pads clean
and free of solder.  Of course, a microscope is the best tool for this type
of work.  Since the leads and pads are very fine, the tinning of the
soldering iron tip is enough to tack a lead in place.  Use tweezers, vacumn
holder, tooth-pick-and-bees-wax to hold the package in place.  Tack one
corner lead.  Then tack an opposite corner lead.  Look and double look to
make sure you have the package aligned.  Then proceed to solder the
remaining pins one at a time.  The tendancy here is to use too much solder.
Try and limit the amount of solder fed onto the pin-pad.  Ample flux helps
the wetting action.  I do not recommend the flood and wick method.  This is
simply too dangerous in that you may damage the part from over heating or
bending a pin.  The major problem with this method can be a solder bridge
that you will have a very hard time seeing under the pins.  They are very
hard to find even with a stereo microscope.

Take a look at the Spring 2006 PSR for a duscussion on the choice of a
microscope

   ftp://ftp.tapr.org/psr/Spring_99_2006.pdf

73,

- Steve, N7HPR
 (n7hpr at tapr.org)




> -----Original Message-----
> From: hpsdr-bounces at hpsdr.org [mailto:hpsdr-bounces at hpsdr.org]On Behalf
> Of Hughes3hns at aol.com
> Sent: Sunday, June 18, 2006 4:11 PM
> To: Christopher T. Day
> Cc: hpsdr at hpsdr.org
> Subject: Re: [hpsdr] Atlas, How do I hand solder this thing?
>
>
> ***** High Performance Software Defined Radio Discussion List *****
>
> Getting old is a real pain... I did a lot better when "Surface Mount"
> meant you bolted it to one side of the board instead of mounting it to
> stand offs....but I'll bet you still can't solder an Altera with your
> two iron method... ;-)
>
> Peter
> N7BMG
>
> Christopher T. Day wrote on 6/18/06, 6:46 PM:
>
>  > Huh, piker. :-) I learned the two iron approach on the RefLock II board
>  > with 0603 parts. The secret is to sneak up on them from behind.
>  >
>  >
>  >     Chris - AE6VK
>  >
>  >
>  > -----Original Message-----
>  > From: Hughes3hns at aol.com [mailto:Hughes3hns at aol.com]
>  > Sent: Sunday, June 18, 2006 2:48 PM
>  > To: Ahti Aintila
>  > Cc: hpsdr at hpsdr.org
>  > Subject: Re: [hpsdr] Atlas, How do I hand solder this thing?
>  >
>  > ***** High Performance Software Defined Radio Discussion List *****
>  >
>  > ...
>  >
>  > And unless you have a Metcal Talon or are extremely coordinated
>  > trying to use two soldering irons to hold an 0805 component will just
>  > result in a nervous breakdown.
>  >
>  > ...
>  >
>
>
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