| Pdelcast |
12.23.2010 01:58 AM |
Quote:
Originally Posted by Freezebyte
(Post 391336)
Im confused by the oven. Isn't the solder already placed by the stencil printer? Is it a special solder that stays in paste like form to install components and then once heated and melts and cools, it turns solid once? How can those delicate circuits survive in that high heat which im guess is like 300+ F?
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That's exactly right -- the solder paste melts in the oven, and then becomes solid when it cools.
The electronics are designed to withstand the "reflow" temperature (which is the soldering temperature) for several seconds. The oven is designed so that it slowly raises the temp, spikes the temp up for a few seconds (long enough for the solder to melt) then cools the board slowly.
The solder paste is designed to be slightly sticky, to keep the parts in the right place on the circuit board. If it wasn't sticky, the parts would bounce all over the board when the placer was putting down parts.
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