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Date: | Mon, 21 Jul 1997 23:32:41 +0800 (SST) |
Content-Type: | text/plain |
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Hi,
I guess you should try to check if the wave-solder pot is being contaminated.
Sometimes, it might due to contamination in the pot, there is solder-bridging
on the smaller chip components such as 0805 or 0603..
Good Luck
Poh
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At 11:44 AM 7/18/97 PDT, Nachbor, Suzanne (MN51) wrote:
>
>We have 0805 chip components with bridging occurring (underneath) after wave
>soldering. 1206 chips placed on the same board with approximately twice the
>adhesive volume do not show any bridging. We have been using this
>component, adhesive, adhesive dot size, and footprint for years and never
>had this problem. The only change that has occurred is our pick and place
>equipment. The default on the new equipment was to place the chip at 3.5N
>force. The old one placed at approximately 2N force (this value is highly
>suspect). We are in the process of doing some testing with placement of
>the chips at different forces to see if this might be our problem. We are
>also looking at the adhesive material and cure times, etc. Has anyone else
>observed similar problems?
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