I am just recently learning how to solder SMDs and wanted to ask for your advice. I have come to realize that my old iron is far too basic to be effective in soldering devices this small, and I would like to invest on a good work station with good products.
So, in your experience what is the best products to use with the best price?
The WES51-120V-ND is a solid, relatively economical unit with a variety of small tips available. Note that good technique will allow you to do quite a bit with even a standard 1/16" spade tip. SOICs, SOTs, 0603 (EIA) passives or larger, no trouble at all. Own one, have one in the cubicle, bought one for a friend.
Advanced hand SMD work calls for a hot air station, which aren't cheap from respected-brand sources. Off-brand units are available on Amazon for much less and can do the job (own one) though as with most such products, you risk getting what you pay for... Good tweezers, good technique, and a stereo microscope will let you do things like 4-ball BGAs with half-mm pitch quite successfully this way.
I'd also recommend use of lead-bearing solder; lower temps, better joints, no tin whiskers...
If you're every tring to do fine pitch chips, flux would be your friend; lightly flux the pad areas and lightly solder one corner pad. A pair of SMD tweezers are very usefull in line up the pins. One you have the chip lined up solder that corner pin and then do an adjacent pin. take a look at it, and if everything looks dandy you can indivindually do every pin, or what I do is glob solder across the pins and use some solder wick to suck up the globs leaving behind small enough amount of solder to make a good connection. Double check for solder bridges and always be sure to clean up with so de-fluxing spray.
Doing it right the first time is important becuase as Rick pointed out, the have SMD chips desoldered you would need special equipment, like hot air stations, or as i use at, metcal that has various tips depending on what you trying to desolder. Tips for metcal and also hot ait stations can run like $150, which to me sounds insane, but sometimes it is required because of the density of nearby components. I am thinking about my boken gpu's at home. I dont have a tip to localize the hot air towards the bottome side of the BGA, then i could start heating caps on the bottom side or losing components near the bga. But the tip costs as much as the GPU at the time, so not worth it to me.
And as far as solder stations, Weller has allows had a good price to qualitly comparison. Tips are inexpensice, and I've learned using those brass cleaners instead of the wet sponge, together with some soldeirng tin, with make those tips last quite a while. I have never liked desoldering smd components with the right equipment, maninly becuase of bent component lengs or ripping the pads off the board. Just happended to me yesterday actually. Got mad, globbed solder across either side of the SOIC and used a simple heat gun until I felt like the solder had liquidfied and tapped on it - chip fell off fairly easily but i could see that when I tried it with a soldering iron the pads when bent out of shaped and some were missing, which is usually the unconnected pads anyways.