++++++++++++++++++++ Date: Tue, 05 Mar 2002 13:15:56 -0600 To: elecraft at mailman.qth.net, Wayne Fowler K0WF , Eric Raub NM0X , Gary Surrency From: Tom Hammond =?iso-8859-1?Q?N=D8SS?= Subject: [Elecraft] ELECRAFT-RECOMMENDED SOLDERS "What brand/type/diameter solder should I use for building my Elecraft Kits?" We've all probably thought it to ourselves, and we've certainly seen it in print here on the Elecraft Reflector... This question appears almost weekly on the Elecraft Reflector, and Elecraft Chief Tech, Gary Surrency (AB7MY) admits that he hears it almost every DAY. In an effort to help answer the question and reduce concern by users, I have been asked by Elecraft to compile a document which, it is hoped, hoped you will refer to the following data when making your solder selection. If you only want to know what solders to buy, you may jump right past the next section and go right to the 'meat' of the subject, to the section titled "ELECRAFT-RECOMMENDED SOLDERS". Also, BE SURE to read the section on what types of solder NOT to use! 73, and as a good friend often reminds us... "Keep the rosin fumes aloft". Tom Hammond N0SS ---------------------------------------------------------------- DEFINITIONS: RESIN A solid or semi-solid organic compound lacking a crystalline structure. Resins are characterized by not having definite and sharp meting points, are usually not conductors of electricity, and many are transparent or translucent. Natural resins usually originate in plants, such as pine sap, and are not water soluble. The rosin used in soldering fluxes is an example of a resin. Also used to describe fluxes based on synthetic resin rather than rosin. ROSIN A naturally occurring resin usually associated a component of pine sap. It is a mixture of several organic acids, of which abietic acid is the chief component. Available as gum, wood and Tall Oil Rosins, sometimes chemically modified. The most widely used material in the manufacture of soldering fluxes for the electronics industry is water white (ww) gum rosin. R = Identity code for a flux which contains rosin without additional activators. RA = Identity code for a flux which contains rosin with additional activators to enable soldering of difficult substrates. Although RA-based material, the residues are not-corrosive if left uncleaned. RMA = Identity code for a mildly activated rosin flux as used for much electronics work. Although RA-based material, the residues are not-corrosive if left uncleaned. Solder Wire = Solder available in small wire gauges, as opposed to BAR solders. Silver-Bearing Solder = A solder alloy which normally contains 2% silver along with 62% Tin and 36% Lead. While this type of solder WAS originally recommended by Elecraft, it has been determined that kits assembled with this type of solder can be more difficult to repair due to the higher melting point of the solder. As a result, there is an increased risk of lifting a PC board land while attempting to desolder or re-heat a plated-thru connection. Elecraft no longer recommends using silver-bearing solder. However, rigs submitted for repair which were assembled using silver-bearning solder WILL be serviced without question. _____________ ELECRAFT-RECOMMENDED SOLDERS (NOTE - This list is NOT exhaustive. However these brands and fluxes HAVE been tested and have been found to be acceptable. There are most certainly other brands, with equally acceptable flux cores also available.) The following brands and types of solder are RECOMMENDED for use when building Elecraft kits. Below this section, I have included a listing of available solders from both Mouser and Digi-Key, just to give you at least two possible sources. Kester RA (Activated Rosin) Type Flux Core types "44", and "285", 60/40 or 63/37 Sn/Pb content in diameters between 0.020" (0.5mm) and 0.035" (0.89mm), with 0.020" to 0.030" being the preferred sizes. ----------- Multicore (previously Ersin-Multicore) RA (Activated Rosin) Type Flux Core Multicore Content Part # Sn/Pb Diameter Spool Weight MM00979 63/37 0.022" (0.56mm) 1 lb (0.5kg) MM00980 63/37 0.024" (0.61mm) 1 lb (0.5kg) MM00981 63/37 0.032" (0.81mm) 1 lb (0.5kg) MM00992 60/40 0.024" (0.61mm) 1 lb (0.5kg) MM00993 60/40 0.032" (0.81mm) 1 lb (0.5kg) MM01020 60/40 0.022" (0.56mm) 1/2 lb (0.25kg) MM01021 60/40 0.022" (0.56mm) 1 lb (0.5kg) MM01022 60/40 0.024" (0.61mm) 1/2 lb (0.25kg) MM01023 60/40 0.024" (0.61mm) 1 lb (0.5kg) MM01083 63/37 0.022" (0.56mm) 1/2 lb (0.25kg) MM01084 63/37 0.024" (0.61mm) 1/2 lb (0.25kg) RMA (Mildly Activated Rosin) Type Flux MM01045 63/37 0.032" (0.81mm) 1 lb (0.5kg) ----------- Radio Shack Rosin Core Solders R / S Content Part # Sn/Pb Diameter Spool Weight 64-017 60/40 0.032" (0.81mm) 0.5 oz (14g) 64-005 60/40 0.032" (0.81mm) 2.5 oz (71g) 64-009 60/40 0.032" (0.81mm) 8.0 oz (0.25kg) 910-3836* 60/40 0.031" (0.81mm) 1.0 lb (0.25kg) * Available through R/S Tech America ----------- W A R N I N G - W A R N I N G - W A R N I N G DO NOT build ELECRAFT kits using solders which contain NO-CLEAN or WATER-SOLUBLE FLUXES, nor should you use NO-LEAD solders! Kits submitted for repair which HAVE been assembled using No-Clean or Water-Soluble fluxes MAY be refused service..! DO NOT USE SOLDERS WITH THESE TYPES OF FLUX CORE Kester "245" No-Clean Solder Kester "331" Water-Soluble Solder or ANY solder with "No-Clean" or "Water-Soluble" flux core. If you have ANY questions about what solder is appropriate to use PLEASE ASK ELECRAFT BEFORE YOU USE IT. ____________________________________________________________ Possible sources for solders. Again, not nearly exhaustive. MOUSER ELECTRONICS ( http://www.mouser.com ) KESTER SOLDERS "44" Rosin, Activated Rosin Core Solder MOUSER Dia Weight STK NO. Alloy (in.) (lb.) 533-24-6337-0100 63/37 0.020" 1 533-23-6337-18 63/37 0.025" 1/2 533-24-6337-18 63/37 0.025" 1 533-23-6337-27 63/37 0.031" 1/2 533-24-6337-27 63/37 0.031" 1 MOUSER Dia Weight STK NO. Alloy (in.) (lb.) 533-24-6040-0100 60/40 0.020" 1 533-23-6040-18 60/40 0.025" 1/2 533-24-6040-18 60/40 0.025" 1 533-23-6040-27 60/40 0.031" 1/2 533-24-6040-27 60/40 0.031" 1 "285" Rosin, Mildly Activated Rosin Core Solder MOUSER Dia Weight STK NO. Alloy (in.) (lb.) 533-24-6337-9700 63/37 0.020" 1 533-24-6337-9718 63/37 0.025" 1 533-23-6337-9713 63/37 0.031" 1 533-24-6337-9710 63/37 0.031" 1 DIGI-KEY ( http://www.digikey.com ) MULTICORE SOLDERS RA (Activated Rosin) Core Solder DIGI-KEY Dia Weight STK NO. Alloy (in.) (lb.) SN6324-ND 63/37 0.020" 1 SN6322-ND 63/37 0.025" 1 SN6321-ND 63/37 0.032" 1 DIGI-KEY Dia Weight STK NO. Alloy (in.) (lb.) SN6022-ND 60/40 0.028" 1 KESTER SOLDERS "44" Rosin, Activated Rosin Core Solder DIGI-KEY Dia Weight STK NO. Alloy (in.) (lb.) KE1103-ND 63/37 0.020" 1 KE1112-ND 63/37 0.025" 1/2 KE1109-ND 63/37 0.025" 1 KE1111-ND 63/37 0.031" 1/2 KE1102-ND 63/37 0.031" 1 DIGI-KEY Dia Weight STK NO. Alloy (in.) (lb.) KE1107-ND 60/40 0.020" 1 KE1118-ND 60/40 0.025" 1/2 KE1116-ND 60/40 0.025" 1 KE1117-ND 60/40 0.031" 1/2 KE1106-ND 60/40 0.031" 1 "285" Rosin, Mildly Activated Rosin Core Solder DIGI-KEY Dia Weight STK NO. Alloy (in.) (lb.) KE1201-ND 63/37 0.020" 1 KE1202-ND 63/37 0.025" 1 KE1200-ND 63/37 0.031" 1 ___________________________________________________________ NOTE: Neither Tom Hammond nor Elecraft have any interest whatsoever in the Kester, Multicore, Mouser Electronics, or Digi-Key companies. Compiled for Elecraft, 02/28/2001, by Tom Hammond (N0SS) ++++++++++++++++++++ Date: Tue, 05 Mar 2002 11:52:54 -0800 From: Wayne Burdick Organization: Elecraft To: Tom Hammond =?iso-8859-1?Q?N=D8SS?= Cc: elecraft at mailman.qth.net Subject: [Elecraft] Re: ELECRAFT-RECOMMENDED SOLDERS Tom Hammond NØSS wrote: > "What brand/type/diameter solder should I use for building my > Elecraft Kits?"... I wanted to thank Tom for his efforts in putting this information together. I hope you find it useful next time you buy solder. Some of you may notice that "No-clean" solder is on the DO NOT USE list. At one point (a long time ago) we recommended this type of solder as an alternative for those who wanted cleaner-looking boards. However, after long experience with it, we determined that it makes component removal more difficult. We've been discouraging its use for the past couple of years. The types that are on the recommended list are pretty conventional solders that do leave some residue. This is OK--you do not have to clean off the boards to make them work. The flux residue from such solder is non-conductive. 73, Wayne N6KR +++++++++++++++++++ Date: Wed, 06 Mar 2002 21:13:01 -0600 To: Gene Fuller , elecraft at mailman.qth.net From: Tom Hammond =?iso-8859-1?Q?N=D8SS?= Subject: [Elecraft] Re: Elecraft recommended solders Gene Fuller, W4SZ wrote, regarding No-Clean solders... ... snip ... >However, I am a bit puzzled why you chose to issue such a dire warning on >the Kester 245 no-clean solder. There is certainly nothing whatsoever wrong >or substandard with this product. Yes, the flux action is not as powerful as >some other solders, but use of the 245 product should not cause damage to >the boards under any circumstances. > >Are you perhaps tarring all 245 solders with the same brush as the 2% silver >bearing version? > >I have been soldering with Multicore and various Kester solders for decades. >When I built my K2 I decided to try the recommended Kester 2% silver >bearing 245 flux solder, which I had never used before. I love it. The >joints look great. I have never had a bad solder joint or a PTTL. I have had >no difficulty whatsoever removing components for adding mods, etc. (OK, so >I use a Hakko 808 for unsoldering.) > >In any case, it is somewhat disconcerting to discover that my K2 is now an >outlaw because I used the recommended solder. 8-) > >You might want to consider separating your warning into those solders that >are genuinely bad, such as those containing water soluble or acid fluxes, >and those that are merely a bit trickier to remove. In fact, I've already done that, in the document which will appear on the Elecraft web site. When I was reformatting (to WinWord format, for Eric) the document for Eric, I realized that I was, at least a bit UNEVEN in my handling of the No-Clean solders. Particularly since Elecraft had, at one time, recommended the use of Kester No-Clean FOR the assembly of its kits. It'd be pretty difficult for me, OR Elecraft for that matter, to place kits built with No-Clean Fluxed solders in the same basket as those assembled using Water-Soluable or Acid Fluxes... and, of course, they should NOT be included there either. While Elecraft no longer recommends the use of No-Clean fluxed solders, kit's assembled using them WILL, of course, be accepted for service. And this is now specifically so stated in the document to appear on the elecraft web site. Finally, Please allow me to insert comments recently received from Gary Surrency, Elecraft's Lead Tech... >The main problem I see with the no-clean solder, is that it wets the solder >connection so poorly, there is a tendency to apply more solder to get the >job done. Any oxides or finger oils on the wires or pads will interfere >with the fusing process. I've used a lot of different solders, and I just >can't see using anything with minimal or weakly active flux - at least in a >kit environment. > >And I am the guy who usually has to work on these kits when the customer >can't get them to work. So, the question is not only whether No-Clean solder's will work for kit building, but how well UNskilled builders might be able to use them, as opposed to RA/RMA fluxed solders, and how readily they can be serviced if the soldering produced by the use of No-Clean solder causes problems. I _do_ appreciate your comments. Thanks, Tom Hammond N0SS +++++++++++++++