Sn60Pb39Cu1 Solder

[JJPOD]

I recently ordered what was advertised as Sn60/Pb40 solder.  Upon arrival, I noticed that the solder was actually Sn60Pb39Cu1 (Weller EL60/40-100).  I could not find too much here on the forum about solder containing a small amount of copper.  However in the build manual for SEX3.0, it say under no circumstances should copper bearing solder be used.  Does this statement even apply to very small amount of copper (and thus avoid this product at all costs)?

[Paul Birkeland]

That product may work for your kit, but I would stick to 60/40 or 63/37.