Regarding the toaster oven technique, I have seen SMDs soldered by placing a
single bead of solder paste on all of the legs, down the entire length of
the chip. Just one bead of solder per row of legs (not sure if I'm making
sense here). Then heat the chip with a heat gun (or toaster) & the solder
will separate between each leg (due to surface tension?) & solder each leg
to the board. Saves time because you only have to put down one bead of
solder. It looks very slick, as it is such a crude method but it works so
well. If you were good at it you could probably solder a 32 pin PLCC to a
board in less than a minute.

Steve

-----Original Message-----
From: pic microcontroller discussion list
[mailto:PICLIST@MITVMA.MIT.EDU]On Behalf Of Wagner Lipnharski
Sent: Monday, November 18, 2002 3:58 PM
To: PICLIST@MITVMA.MIT.EDU
Subject: Re: [EE]: SMD Soldering, was Printer to PCB?


Roman Black wrote:
> Wagner Lipnharski wrote:
>
>> Roman, how do you deposit the solder paste over the board's SMD pads?
>
>
> Just spot or "line" with the solder paste syringe,
> I got a 19 gauge needle from the pharmacist (the
> real BIG one you don't want to ever see in your
> doctor's hand) cut it to 10mm length and filed
> the cut end very smooth and flat. Alexandre G said
> to always use the good paste with 2% silver and
> I followed his advice. :o)
> -Roman


I just used the very narrow plastic noozle it comes with, around 1mm line
can be poured.
The idea of using a X/Y home made plotter with a paste spitter would be
great.

Wagner.

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads