On 09.05.15 23:21, Gene Heskett wrote: > > As far as I can tell the best selective soldering machines use a > > solder fountain. > > That I am not at all familiar with.
A static solder bath may be used to solder one connector or one chip to a board, but the production-line "solder baths" I'm familiar with feed boards through on a conveyor, preheat with infra-red lamps, then the board slowly traverses a centimeter above a bath of molten solder with a board-wide rectangular tube protruding a millimeter. As the board approaches, the solder pump starts, and a wave of solder fountains, striking the underside of the passing board. It gives complete through-hole solder penetration in half a second. More importantly, I guess, the inevitable surface oxide dross is entirely absent from the wave, having instantly slid to the surrounding lower pool. That pretty much eliminates solder bridges, so long as the board is fed perpendicular to the rows of chip pins. We always laid them out one way, to make that easy, and simplify chip insertion. (Dunno what the rules are for SMD) I think that the operator skimmed the bath now and then, but on my few escapes from the design lab to the factory, boards just went through on their own, at a steady pace. (Up to "double-euro", which is 220 x 160 mm, IIRC. So a modest sized bath.) Erik -- In the bathtub of history the truth is harder to hold than the soap, and much more difficult to find." - Terry Pratchett ------------------------------------------------------------------------------ One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
