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Where is the sensor that the oven uses to measure the temp? - it would be great to know to compare accuracy of the results.
It is worth noting that the temperature displayed on the oven is different from the temperature measured on the PCB by a lot - up to 30 C, even in lower temperatures.
General Reflow Tips
- Preheat the board to bring the board up to temp to reduce the chance of cold solder joints if the whole joint is not up to temp
- Don't make the preheat period too long or else all of the flux will dry out
- Every component usually has a recommended reflow profile in the datasheet (or at least max temps), as well as the solder paste
- We will follow the recommendation for the solder paste, as this
- etc.
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The desired temperature is reached and slightly surpassed, but temperature is not stable between peaks which could affect the quality of the solder.
The following figure shows the temperature of the edge of another copy of the same PCB. The same pattern as above can be observed, but the temperature is notably higher than what was measured in the center of the board.
