Electronic – Homemade printing and soldering for small components.. the best way

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Which is the best way to solder small components such as SOIC or QFP44 packaged components to a PCB without using adapters?

And how can I manage to print PCBs with small track distances and widths for those type of packages?

Best Answer

Drag-soldering works very well for me. Tack down two opposite corners ensuring that the chip is correctly positioned, apply plenty of jelly flux, put a small blob of solder on a medium tip and drag it along each row of leads. Remove any solder bridges with desoldering braid. I use a mini-hoof cartridge with my Metcal system which is specifically designed for drag-soldering.

I often make my own PCBs at home using the photo-etch process; the UV exposure unit cost me about £20 to make, and I print the transparencies on my HP inkjet printer. I don't have any problems with fine-pitch devices, and can go down to 8/8 mil track/spacing. I normally use 10/10 or 12/12 mil, though.