I need to assemble and test a rather large (40x30 cm) board with single sided SMD parts, Sn Ag Cu solder (officially 217°C melting point). Usually I place group after group of components and locally solder these groups with a "hot air pen" (rework solder station), which works beautifully.
However, this method does have problems when parts are tall and contain a lot of temperature sensitive material like plastic connectors or electrolyte caps. For those parts, the hot air can heat the parts way higher than the 260 °C they are usually rated for, before the solder starts to melt, leading to damaged components.
Is there a reliable way to solder such parts when a proper reflow oven is not available ? In particular, I have a plastic multirow SMD connector with a BGA like landing pattern (Samtec SEARAY) that I don't know how to solder well.
I do have the following:
- hot plate up to 300°C
- hot air pen
- kapton tape
- a large convection oven which goes to maybe ~210°C (doesn't reflow reliably).
Unfortunately the board doesn't make good contact with the hot plate because it warps upwards when heating the backside