Process control of hotbar soldering

▪ Control the gap between the thermode head and the object to be pressed (usually PCB). When the thermode drops to the object to be pressed, it must be completely parallel to the object to be pressed, so that the object to be pressed can be heated evenly. The general method is to loosen the screws which are locked on hotbar soldering machine by the thermode first, and then adjust them into manual mode. When the thermode is lowered and pressed on the pressing material, confirm that after full contact, screw the screws tightly, and finally raise the thermode head. Usually the object to be pressed is PCB, so the thermode should be pressed on the PCB. It is better to find a non tin board to adjust the hotbar soldering machine.

▪ Control the fixed position of the object to be pressed. Generally, the objects to be pressed are PCB and flex board. It is necessary to confirm that the PCB and flex board can be fixed on the fixture carrier. At the same time, it is necessary to confirm that the position of hotbar is fixed each time, especially in the front and rear directions. When there is no fixed object to be pressed, it is easy to cause air welding or crush the quality of nearby parts. In order to fix the object to be pressed, when designing PCB and FPC, special attention should be paid to the design of adding positioning holes, preferably near the hot pressing of molten tin, so as to avoid the displacement of FPCB during pressing.

▪ Control the pressure of the hot press. Please refer to the recommendations provided by the hot press manufacturer.

▪ Need to add flux? Flux can be added as appropriate to facilitate smooth welding. Of course, it's best to achieve your goals without adding it. Because the flux in the original solder paste has evaporated after the solder paste is printed on the circuit board and flows through the reflow furnace, when pressing hotbar, it is usually necessary to add flux once to improve its welding ability. The purpose of flux is to remove oxides.