Same idea but simpler execution.
Verify Solder pot temperature.
Verify Temperature of Solder as it leaves the nozzle.
Verify preheating gets your PWB up to 90C-120C prior to soldering.
Check machine speed, verify 4 seconds contact with solder at each lead. Verify that max component temperature is not exceeded during contact with the solder.
All the above can be done with a handheld thermometer and some flexible thermocouples.
After that, your variables are PWB weight(mass) and thickness. Extend preheat time to achieve 90-120C, and slow down the movement to assure the barrels are meeting the minimum fill requirement.
Hope this is of some help. Don't overthink it.
'hege
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