ben lipkowitz wrote: > On Thu, 28 Feb 2008, Kirk Wallace wrote: > >>I am getting ready to assemble my DAC boards (SMT, 8-pin SOIC's). Does >>anyone have a favorite lead free solder and paste? Thanks. I got a sample of Sn100 (100% tin) and it was impossible to do anything with. I then got some SAC305 (3% Silver, 0.5% Copper, balance Tin) and it works much better, but is still harder to get good joints with than plain old SnPb solder.
The SAC305 paste I use is Kester R520A. There are a million variations, such as water-washable, no-wash, solvent-wash, different viscosities for syringe applicaton vs. stencil application, etc. If your boards are not made with high Tg (Glass temperature) you may have serious burning of the boards when you get them up to 240 C to reflow the lead-free solder. I have to pay significantly higher prices for high-temp boards for the lead-free process. If I don't, then rework is impossible, the traces and pads just fall off the board. Jon ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
