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For a while I've been fiddling with electronics, designing my own pcb's and soldering a lot of thing together, which is lots of fun. I've become quite comfortable soldering small parts, like 1206 resistors (by hand) and SOT-23 packages (solder paste + hot air).

I now often come across parts that are basically supposed to be used in a professional way, by pick and place machines, for example, parts like TPS63001 (3x3 QFN package) or the MAX17043G+U (TDFN-8) and was wondering if I should attempt to use them and what would be the best approach. I know that using parts like those are best suited to be picked & placed in a automated way, but price wise that doesn't really seem to be a option for one off prototypes.

If I want to solder these parts manually, what kind of equipment should I be looking at? (Or should I not attempt using them at all? ) I currently only use a soldering station (a cheap baku) that also has a hot air gun, which is ok, but not perfect, so I was already thinking about buying a proper soldering station (maybe a weller). Would hot air be a good way to go with these small parts, or should I look at hot-plate soldering or even a reflow oven? Should I look into some device for magnification? maybe a electronic microscope? And what about a solder paste dispenser? would it be more suitable than stencils for one-offs? Any other tools that would be required for this work?

My main problem with soldering paste is currently that I don't have a proper way of putting the right amount on for these small parts. Usually I pot on too much which leads to shorts in the circuit.

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  • \$\begingroup\$ Firstly, the TPS63001 device has a thermal dissipation pad on the underside. If you're relying on this pad to have a good connection I wouldn't recommend it by hand. Usually components come in at least 1 hand solderable package, if not, there's always alternatives available \$\endgroup\$ – Doodle Mar 29 '17 at 14:57
  • \$\begingroup\$ Normally (relatively) easy hand soldering stops at about the 0805 level. Beyond that you will probably need a good magnification device. We use a stereo microscope specially bought for the job. \$\endgroup\$ – Dirk Bruere Mar 29 '17 at 15:39
  • \$\begingroup\$ 0402 is no problem by hand, and all I use is eyeballs and a cheapass soldering iron bought at a home improvement store. Anything that doesn't have the pads underneath (bga or thermal pad on the bottom) can be hand soldered. \$\endgroup\$ – JRE Mar 29 '17 at 15:57
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There are two main techniques to hobbyist SMT soldering: hand soldering, and reflow. Hand soldering uses an iron, solder, soldering wick, and sometimes flux. Reflow often involves applying solder paste, which consists of little beads of solder suspended in flux, to the pads of the board, placing the components onto the pads, and then heating the assembly to melt the solder creating a joint.

This is taken from the following; https://www.wayneandlayne.com/smt/

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  • \$\begingroup\$ I know soldering paste is the way to go, but what equipment would be best suitable with small parts, especially those that have thermal dissipation pads underneath? Would a hot air gun be sufficient? or is a hot plate better, or even a reflow oven? \$\endgroup\$ – ErikL Mar 30 '17 at 7:06
  • \$\begingroup\$ EEVblog has a playlist with soldering tutorial videos. It particularly includes some videos about soldering chips with thermal pads. You may find it useful \$\endgroup\$ – GAttuso Mar 30 '17 at 7:58
  • \$\begingroup\$ The equipment you use will be determined by the task you are trying to accomplish and your comfort level. On my own prototype boards I like to use the Weller WCL100 solder station. On repairing some notebook PC mother boards I believe an oven works best, others my have a different opinion. \$\endgroup\$ – MEZLAW Mar 30 '17 at 19:54

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