This page documents my heat profiling experiment with a $20 Aroma
hotplate. The hotplate takes about 3 minutes to hit melting
temperature, but quickly heats to burning temperature, and the heat is
uneven. So, keep the board moving so it heats evenly, and be prepared
to remove it from the hotplate when it's done.
2:55 - The spots over the heating coil start melting
3:08 - the innermost spot on the outer area melts.
3:35 - the outer most spot melts.
3:40 - the first spot in the center area melts.
4:23 - The last spots at the center of the hot plate finally melt.
So, it's about 40 seconds to do the whole outer ring if you don't move
the board around. Moving it around would shorten the elapsed time by
making the temperature more even, so everything hits the melting
temperature together. We hope.
Note: for those of you who are unfamiliar with reflow soldering,
the second movie shows what happens when the paste melts.
There's no uncertainty about it when it happens.
