On Saturday 27 August 2005 03:48 pm, Darrell Harmon wrote: > I have not used stencils yet, but I may give it a try now due to the low > cost. I have a blank DSPcard that would be a really good test (except for > the $120 worth of parts involved). It has a LQFP176 and a FT256 BGA. I > have previously soldered the BGA in a toaster oven with no paste and > everything else with an iron. I don't see the stencil being too beneficial > for the LQFP (takes about 45 seconds to solder by hand), but the 0402 caps > are not much fun to solder (there are 57). We use stencils in our shop - Stainless steel. I've never used the disposable ones. Even with stencils, no matter how good you get at using them, occasionally you have to use an iron to clean up pins that have solder bridges. Small ceramic caps and resistors are easy: Glue them to the board with a tiny dot (And I mean small...) of locktight (The stuff for screws and such. Although, I'd imagine you could even use white school glue). You put the small dot of glue in the center between the pads so when you put down the capacitor or resistor, the center of the device is glued to the board. Let it dry and then you can either put solder paste at the ends or solder them by hand. we use handheld pick and place vacuum pins for this type of work - In both prototype and repair. But, I'm sure you could do it with other tools like very fine gauge tweezers. Regards Marvin
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