07-14-2009, 12:29 PM
I haven't been to the "Engineer's Technical Workshop" in quite a while, but today I'm suffering from a cold so I'm looking through forums I don't always have time to peruse. This is an old thread, but I think this bit of info is important to share. In California they are trying to get rid of lead in everything. The last time I looked at solder in a Home Depot, they had gone lead free, and the lead free solder was 95/5. 95/5 is 95% tin and 5% antimony if I remember correctly (might be the other way around). It needs to be heated about 200 or 250 degrees hotter than lead solders. We used 95/5 in refrigeration work because it is much stronger than 50/50 or 40/60. Occasionally I would come across a refrigeration unit that had been repaired by a plumber, and the discharge line would be blown right off the unit. It had a good solder connection, but the solder was not strong enough to handle the pressure. I hardwired a motor in an Athearn that I donated to the modular club for use pulling our track cleaner cars around the layout. When the club went to dcc, one of the guys needed to rewire to isolate the motor from the frame. He asked me what I had used for solder? None of his usual soldering irons would melt it! He ended up alloying the solder with other softer solders to get the wires apart. If the Home Depot or other big box home improvement store has discontinued the lead based solders and switched to 95/5, or the even newer silver bearing solders, you will need a soldering gun or a really big iron to get the solder hot enough. The last time I looked, Grainger still carried 50/50 and 40/60.