In a message dated 01/19/2000 9:55:42 AM Central Standard Time,
[log in to unmask] writes:

<< Ok..so what are the causes of solder beads?? >>

Hi Jan!

Solder beads or "Squeeze balls" as they're sometimes referred to, are caused
by too much of the gray stuff...solder paste. In a cleaning environment
they're usually not a problem because they wash off. But in a no-clean
environment, BIG headache!

They can be eliminated by modifying the apertures in your stencil to reduce
the volume of paste you're putting down. Instead of square apertures you can
turn them into triangles or "homeplates" with the pointy ends pointing
towards each other to the center of the footprint. A lot of  stencil vendors
will do this automatically...at least mine does. I just tell them I want
no-clean apertures for all the passives...I think it's an extra $25-50 charge
for the editing they have to do in the gerber.

Hope this helps...

-Steve Gregory-

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