On 11/6/2019 10:02 AM, Dave wrote:
Harvey,
? I was hoping to avoid "lead free" solders altogether but I am sure there is a good reason for them.
The reason for lead free solders is that a lot of the electronics equipment gets dumped in a landfill.? The lead leaches out and gets into the ground.? In the EU, environmentally conscious people decided to mandate that lead be removed from electronics equipment, thus causing the switch to lead free solder with the included difficulties.
I will continue to avoid them as long as I can. But, that brings up a new question. Now that I am starting to gather the goods to try SMD pcbs, I have run into a small issue. I have a bunch of thru hole PRC fuses and when I tried to hunt down a SMD alternative from LittleFuse, all they have is the "lead free" variety. Can a lead free component be soldered to a copper clad pcb with tin/lead solder?
Easily.? Just ignore the lead-free solder and use standard solder.? I have a number of parts that are ROHS (Reduction of Hazardous Substances), and they seem to solder just as well.? OF course, the PC boards I get from China use standard tin/lead solder.
Or would I have to use lead free solder on that one component?
I've not had a problem.
Or better yet, mixing thru hole and SMD components on the same board is not a problem I guess?
Design wise, no, not a bit of a problem.? They're just parts.? On my latest designs, almost everything is SMT with the exception of the so called "dupont" connectors, standard through hole pin connectors you connect either IDC or single row (tektronix style) wire connectors.
One reasonable thing to do is to make jumper cables with the standard Chinese socket to socket connectors (they're a bit long, but if they fit....).? You just buy a connector kit and replace the plastic shrouds with a single piece, inline or not.? Does very well for test connectors.
Harvey
Thanks,
Dave
On 11/5/2019 6:45 PM, Harvey White wrote:
Lead free is, I think, tin, bismuth, and silver (might have remembered this properly).? However, it does not play well with low temperature soldering and is (AFAIK) inferior in all respects to what one would want in solder.? I have never heard of a eutectic mix, so the low melting temperature doesn't happen with lead free.? This puts more stress on parts, let alone makes soldering more difficult.? Yep, tried lead free, didn't' work as well.
Now the chip-quik has a much lower melting point (IIRC, pure bismuth has a rather low mp, but again, could be wrong).? The chip-quik is designed to alloy and melt at a lower temperature, making removal of large ICs easier.
They do say that you can use it for soldering directly, but that's a good question about how and what.
Harvey
On 11/5/2019 4:49 PM, Dave wrote:
Thanks Harvey,
? I bought a syringe of as per Stefan's post above. I have read about a foreign brand named Mechanic that most people give it high marks.
I also watched some video's earlier today about flux cleaners and in one of them they said MG's the winner.
Isn't bizmuth the stuff that is in lead free solder, or is it some new type? I guess it is a new type because from what I read, lead free has a higher melting point that no lead solder. I have no clue as I never tried it.
Dave
