Due to a careless selection of components (and you could say also bad layout) I ended up having a PCB with surface mount pads on both sides and on the same x,y coordinates.
I have already used my airgun for the TQFNs on one side but I have to solder some more on the other side and I am worried that by applying heat with the airgun, the already soldered chips will drop off from the bottom as I am heating up the top side.
Has anybody dealt with this issue before and if so, how do I ensure that what is already soldered will stay there despite the extra heat.
I've thought about putting Kapton tape or simple tape to hold the bottom components in place while I heat up the top side but then this could trap the heat around the components and make them desolder easier.
What I am planning on doing is simply place the PCB on a table so that the bottom components are sandwiched between the PCB and the table and they will hopefully not move out of place even if the solder melts while the top side is being heated up.