On 2013-04-18, at 8:34 PM, Carey Fisher <careyfisher@ncsradio.com> wrote:

> I've done a large number of small quantity SMT board runs as follows:
>=20
> 1.  Using a syringe of solder paste with the smallest tip provided, put
> tiny dabs on pads of Rs, Cs, Qs. For ICs, run a thin line of paste over t=
he
> pads on each side.
> 2.  Hand place the parts with reasonable alignment using tweezers and
> magnifier.  The paste will hold the parts in place.
> I made a parts holder using a bunch of small tin cups mounted to a board.
> Each cup has a ref designator next to it and the parts go in the tins
> before I start placing.
> 3.  Stick the boards in a toaster oven at the highest temp it will go to.
> 4.  Through the window, watch the solder melt (turn shiny) starting at th=
e
> back of the oven and progressing to the front. It's kind of fascinating t=
o
> watch!
> 5.  Surface tension of the melted solder near always aligns all parts
> perfectly. It's magic!
> 6.  Magic comes with a price:
> 7.  Once you've seen all the solder melt, turn off the oven and open the
> door.
> 8.  After the boards cool down enough to handle inspect with a magnifying
> lens.
> 9. You may have to use thin solderwick to remove the solder bridges on so=
me
> ICs.

This is pretty much the same process as the one I follow=85.although I went=
 all-out and bought some of those little antistatic snap-together container=
s from Schenzen for parts :)

It's definitely a lot easier, quicker and more precise to get your parts se=
tup in cups/containers and use a "cheat sheet" with the board ref IDs mappe=
d to the containers! At first I had strips of 0603s on the table and would =
peel back the backing, reveal a part, try and place it, lose it, peel back =
a bit more=85.you get the idea.

Good advice.

-m


--=20
http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist
.