For those that grew up working with through-hole components, surface mount parts can be challenging to deal with. However, there are plenty of techniques out there that are more than accessible to the DIY set. With the right gear, soldering SMD boards is a snap – just get yourself a hot pan of sand (Youtube link, embedded below)!
The process starts with a professionally manufactured PCB, and accompanying stencil. All major PCB CAD packages are capable of generating stencil files these days, and many manufacturers will throw in a laser cut stencil for minimal extra cost with a PCB order. The board is first mounted on a stable surface, and has solder paste applied, before components are placed with tweezers. Perfect placement isn’t necessary, as the surface tension of the molten solder pulls components into their correct orientations. The populated board is then placed on a bed of sand in a frying pan, which is placed on an induction cooktop. The board is then heated until the solder melts, and all the components are neatly reflowed. Once allowed to cool, the board is done!
The trick is that the sand helps evenly heat the circuit board, while keeping it a safe distance away from the heat source. Results are good, and the process is far quicker than hand soldering. It’s easy to keep an eye on the process too. Of course, the traditional method is still to use the humble toaster oven, but new techniques are always useful. We’ve seen it done with a Bunsen burner, too. Video after the break.