Nitish Gupta, business development, Advance Tech Services, says, “Defective surface-mount components can be repaired by using soldering iron or by using a non-contact rework system. In most cases, a rework system is the better choice because SMD work with a soldering iron requires considerable skill and is not always feasible. Temperature accuracy is of utmost concern. RX-802 has a patent six-seconds heat recovery used with a reflow bit for SMT soldering that delivers better and efficient working without shorting and bridging.”
Coggeshall gets a piece of equipment called 898 rework station for about US$ 88 through AliExpress. It is called so because the first Chinese company used that name and now eventually there are a dozen companies using the same name. Coincidentally, the ovens are the same, too. These all look the same on AliExpress or Alibaba. The 898 is a combination of hot air and soldering iron—the hot air is truly indispensible for surface mount rework. There is a set of skills you need to hone if you have to reflow, and you have to use a solder wick to remove solder.
Hot air will usually help you take care of most reflow unless you have something exotic or very small. An exotic component is a lead-less component like the one on Arduino Leonardo quad-flat no-leads where the central processing unit is a small black rectangle. If you have one in hand, look carefully at the perimeter and you will see small dots. That part is impossible to work on without hot air.
There is one more piece of equipment that is basically a bed that heats up—Aoyues66, a toaster oven that sits on your desk and costs approximately US$ 200. When you place your board on the bed, it will heat up the whole board from the bottom. It also has a little arm over the board and a hot-air gun that blows hot air down on the board. These are the last resort if you have rework to do like when you have a ball grid array with pins on the bottom; this may be the only way to get to that part of the board. For light emitting diode arrays that are closely placed, this is the only way to get densely packed parts of the same.
The author is senior editor at EFY. He is B.Tech from University of Calicut, and is currently pursuing MBA from Christ University, Bengaluru. This article was written with major inputs from Bob Coggeshall, who runs Small Batch Assembly, a small, maker-centric business from NoVa Labs in Reston, Virginia, USA