EMRFD Message Archive 466

Message	Date	From	Subject
466	2007-02-13 11:47:46	Ted Bruce KX4OM	More X-Pad photos with BF998
Hi all, I added four pics to JR's album on X-Pads. The upside-down mounted BF998s fit snugly in a 1/8" punched hole, but at least one leg barely touches the foil. Although you can barely see the legs, one is mounted right-side up over a 3/32" hole. I'd like to see someone more experienced than me in SMD techniques try this. I used regular (small diameter) 63-37 Kester solder with no paste. I need to finish my LED ring flash project. The photos with the pink anti-static bubble-wrap background were made with a 1.4 M-pixel Sony, whose flash was better positioned for macro work. The blue background (mouse pad) was done with a Nikon N-990 3.3 M-pixel ($900 in it's day!), but the flash is further away from the lens than on the Sony, so I got shadows. Ted kx4om
467	2007-02-13 12:03:12	Don Hackler	Re: More X-Pad photos with BF998
Ted Bruce KX4OM wrote: > Hi all, > I added four pics to JR's album on X-Pads. The upside-down mounted > BF998s fit snugly in a 1/8" punched hole, but at least one leg barely > touches the foil. Although you can barely see the legs, one is > mounted right-side up over a 3/32" hole. > > I'd like to see someone more experienced than me in SMD techniques try > this. I used regular (small diameter) 63-37 Kester solder with no paste. > A bit of solder-wick to soak up some of the excess solder would clean them up very nicely.
469	2007-02-14 11:01:00	Ted Bruce KX4OM	Re: More X-Pad photos with BF998
Thanks, Don. I was just researching SMD soldering techniques, and one of the items I came across was to wipe the braid (with the iron, of course) across the legs of soldered SOIC devices, right down each row. I'm sure that's old news to those experienced in SMD soldering, but all of these tips are news to me! 73, Ted kx4om
471	2007-02-14 13:38:32	Don Hackler	Re: More X-Pad photos with BF998
Surface mount means you pretty much have to "unlearn" a big portion of your traditional solder techniques. Most of us learned to make a good mechanical connection followed by a good wet "fillet" of solder. The solder was never supposed to be the mechanical connection. With surface mount, the solder is the only connection, and you end up using the minimum amount of solder. All you want is the parts to hold by capillary action of the solder to hold the part while the solder is melted. The solder braid will soak up any excess solder. Brush
473	2007-02-14 16:02:31	Ted Bruce KX4OM	Re: More X-Pad photos with BF998
Good comments again, Don. I have the flux that's rather thick, that comes in a short squeeze tube (RadioShack item). I also have a chiseled felt-tip flux applicator that I ordered from Mouser, but the flux itself seems kind of thin. I'll have to try it with some SMDs to see if I can get it to hold in place long enough to tack down one leg. I use an extension arm lamp for bench work, and I have the wearable flip down magnifiers..the big black thing, basically like the $5 versi