Hi ya'll!!

I wished this little beast lent itself to a selective wave soldering pallet,
but it don't. Go to: http://www.driveway.com/share?sid=e25a88c4.8e904&name=Pic
tures
and look at "Funwave.JPG" to see what I mean.

You can see by the dime I put there how big it is. This comes in a 10-up
panel. There's about a dozen SOT's, eleven-1206's, and around thirty-0805's
on the backside. Up top there's three-14-pin, one 8-pin, and one 6-pin DIP
IC. There's also one 5-pin right angle header, as well as two radial caps,
one axial fuse, and a 3-pin PTH transistor.

The 14-pin straddle mount connector and the two LED's have to be hand
soldered because they also straddle the board. The variable resistor on the
backside also is hand soldered because it can't be waved...fun stuff huh?

We do get skips...mostly on the SOT's that I've seen...Mike said he's seen
some on the other passives as well. We do get other defects because of the
layout of things on the bottom. Those two 1206 caps in the upper right corner
bridge quite a bit, and there's always the excess solder on the leading edge
of a component that's oriented the wrong way to the direction of travel in
the wave.

Me and Mike have been discussing this wonderfully designed board. My opinion
is that using paste and adhesive may take care of some of the problems, but
with this board there's always going to be touch-up.

I also ask myself what new problems might be introduced dispensing adhesive.
The last "good" dispenser I've used was a FUJI FGL-V...and back then we did
have some issues with epoxy bleeding on to the pads with SOT's as well as the
"tail's" stringing onto the pads when things weren't working as well as
planned...

One last issue we talked about was an experience I had at a past company
where we printed paste and dispensed adhesive. What would happen during
reflow was when the paste would hot slump, some of the paste would embed
itself into the epoxy, and then cure...so we had all these little solderballs
cured into the epoxy. Our customer wouldn't take the boards like that, and we
wound-up eating them...

-Steve Gregory-

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