What soldering wire should I use? - Page 1
Forum section: electronics / general

author: xReM1x
author_rank: Regular Contributor
timestamp: March 18, 2015, 12:17:31 pm
content: Hi,I'm looking for good soldering wire on ebay, (low cost shipping to israel) and I found those:http://www.ebay.com/itm/110-GRAM-REEL-OF-HIGH-QUALITY-LOCTITE-MULTICORE-LEADED-SOLDER-/311314439315?pt=LH_DefaultDomain_3&hash=item487bc95c93http://www.ebay.com/itm/MULTICORE-SOLDER-D9922-2METRE-SOLDER-WIRE-LEAD-FREE-0-7MM-X-2M-/171365024395?pt=LH_DefaultDomain_3&hash=item27e626c28bhttp://www.ebay.com/itm/2Meter-2M-MULTICORE-X-39-Flux-63-37-1-02mm-Solder-/151609947028?pt=LH_DefaultDomain_0&hash=item234ca83394What should I order?

author: Zucca
author_rank: Unknown
timestamp: March 18, 2015, 01:01:02 pm
content: Quote from: xReM1x on March 18, 2015, 12:17:31 pmWhat to you need to solder?For fine work pick a small diameter. The opposite for big soldering job. Pick a good brand,do not go cheap. Soldering wire is the basis for a good and high quality result.

author: TimFox
author_rank: Super Contributor
timestamp: March 18, 2015, 01:18:36 pm
content: You are looking at different alloys in this list.Lead-free solder is now required for ROHS regulations, but is not so easy to use as traditional leaded solder. If you want to keep your tools to meet ROHS, you must always use lead-free solder on your iron. Lead-free solder is also required for plumbing on drinking water supply pipes. I won't enter into the ROHS: threat or menace? debate.For leaded solder, 63-37 SnPb is the "binary eutectic" alloy, which melts cleanly. Another alloy, which is becoming harder to find, is 62-36-2 SnPbAg, with a smidgeon of silver in a "ternary eutectic" alloy that melts cleanly at a slightly higher temperature and looks shinier when soldered properly. Eutectic alloys melt and freeze at the same temperature, without passing through a mushy stage.Lead is toxic, especially to children, and should be handled carefully. Lead-based solders now come with safety instructions.ROHS components can be soldered with either solder, but the pad design for leaded and unleaded solders differs due to different flow properties of the alloys. Of course, if you solder a ROHS resistor with leaded solder, the result is non-ROHS.I wholeheartedly agree with zucca's comments above. I keep two rolls of solder next to my iron, both SN62, in 0.050" and 0.025" diameters. Kester and Multicore are both high-quality brands.

author: VK3DRB
author_rank: Super Contributor
timestamp: March 19, 2015, 10:21:30 am
content: Quote from: TimFox on March 18, 2015, 01:18:36 pmWhere have you read that from? It sounds like rubbish. If you clean the tip, virtually no lead will contaminate the product. If you swap the tip for a ROHS only used tip, absolutely no lead will contaminate the product.It is odd how the European Greenies have concocted this ROHS directive, and yet have Chernobyl living next door and places like France infested with nuclear power plants.

author: Someone
author_rank: Super Contributor
timestamp: March 19, 2015, 10:30:29 am
content: Quote from: VK3DRB on March 19, 2015, 10:21:30 amThe ROHS compliance trolls will have you believe you need to have side cutters that have never touched leaded joints lest you contaminate their precious product, it all gets a bit crazy.

author: John Coloccia
author_rank: Super Contributor
timestamp: March 19, 2015, 10:31:59 am
content: Quote from: VK3DRB on March 19, 2015, 10:21:30 amMixed use tools is a major source of contamination and will easily bump you over the RoHS limit. The limit applies to every teeny tinniest part of the product, not the product as a whole. If there is just one joint, or even just part of a joint, that is over the limit, the entire product fails.Anyhow, a small amount of lead in the solder makes for a lousy joint. It's much better to have dedicated RoHS tips and cleaners that never see lead.

author: Ian.M
author_rank: Super Contributor
timestamp: March 19, 2015, 11:16:12 am
content: The ROHS limit is Lead (Pb): < 1000 ppm. That is a 0.1% limit on Lead concentration.Start with a tip that has been used for Lead/Tin solder, wipe your tip as clean as possible, and tin it generously with lead free solder, and you've just reduced the Lead concentration by at least a factor of ten by simple dilution. Repeat two more times, and as long as your Lead free solder is well under the ROHS limit, your tip is certain to be under the limit as well.Its almost always OK to simply wipe and tin twice then wipe. You don't start from 100% lead, and the reduction per wipe/tin is usually more than a factor of ten + any traces will be further diluted in the first joint so it meets the limit.Of course, its good practice to have separate bits, and separate tools makes sense as then you can colour code everything including the solder reels and avoid mix-ups, but if you have to switch from non-ROHS to ROHS compliance doing field repairs, with a limited toolkit, clean the iron properly and you will be OK as long as you have the correct solder.Similarly, if you have to do an emergency non-ROHS repair on a ROHS board or visa-versa, desolder and clean the joint, resolder, desolder and clean again, and you have reduced the concentrations enough that there will be no problems with embrittlement when you finally make the joint.

author: nctnico
author_rank: Super Contributor
timestamp: March 19, 2015, 11:32:02 am
content: When it comes to lead free solder I'm quite fond of alloy 99C 5C 502 from Multicore. It is easy to work with and gives me joints which are almost as shiny as leaded joints (using a tip which big for the job and the temperature set at 330deg C). For leaded solder I also stick with the Multicore brand.

author: John Coloccia
author_rank: Super Contributor
timestamp: March 19, 2015, 12:29:56 pm
content: Quote from: Ian.M on March 19, 2015, 11:16:12 amProducts have failed and been caught, and it's been traced back to multi-use tools. If you care about being compliant, then you do it right. If you don't care and want to wing it, then wing it. Also, as I said above, even a TINY amount of lead mixed in with lead free solder will make for a terrible joint. You can solder RoHS components and PCB finishes with lead solder because it doesn't care about small bits of lead-free alloy, but lead free alloy does NOT work with small amounts of lead in it.Anyhow, I had a nice, long conversation with a chief head mucky-muck scientist type guy at Kester, and he recommended Kester#48 K100LD. It's compatible with the standard 186 flux (same as with industry standard Kester 44 leaded solder), and makes great joints. I'm not sure what the alloy is, but he may have even mentioned it's eutectic. I found it does seem to make the best joints for hand soldering of anything I've tried. Incidentally, he also recommended ENIG finish.

author: TimFox
author_rank: Super Contributor
timestamp: March 19, 2015, 12:32:46 pm
content: My previous day job involved digital x-ray imaging systems, and we had to convert our electronics production to ROHS. To comply, we were told by corporate to use dedicated soldering equipment to avoid contamination. This was amusing, since our megavolt imaging systems often used literally a ton (or tonne in the EU) of lead for safety shielding alongside our ROHS-compliant electronics.For those who, like me, do not sell electronic products, there seems to be no reason to switch from leaded solder, following normal safety procedures. However, for those who work or seek work as electronic technicians, it is probably better to practice with lead-free solder to perfect their soldering at work, since the melting and flow properties are noticeably different.

author: Mechanical Menace
author_rank: Super Contributor
timestamp: March 19, 2015, 01:33:32 pm
content: Quote from: VK3DRB on March 19, 2015, 10:21:30 amNot only the OTT green lot tbh. Not only did the lead contamination decimate of the ecologies of an awful lot of our waterways, it's pretty certain that the drop in violent crime at the same time as the drop in lead contamination in the environment is causally related and not just a correlation. It wasn't just done at a whim to make environmentalists feel good, it was to fix a real problem and ended up helping problems we didn't even realise were related.Chernobyl also isn't in the EU, and nuclear power is relatively safe compared to most other options.