Kester24-9574-1402 K100LD, Lead-Free, Rosin Wire Solder, .031" Diameter-Low Cost Alloy, 1 LB Spool

This is a good lead free solder wire with a Kester 48 RA flux core. K100LD alloy is eutectic so it doesn't have a plastic range that can accidentally be disturbed. Kester 48 is a good flux like Kester 44, in fact I find Kester 48 even stronger which is good for lead free solders. According to the data sheet you don't have to clean Kester 48 but it's not a true no clean flux.

This solder has truly been a revelation for me. Making the switch from lead solder was a conscious decision, both to minimize exposure for my employees and to contribute positively to the environment. However, my past experiences with lead-free solder left me somewhat disappointed due to its performance limitations, particularly its poor wicking capabilities.But this solder has completely changed the game. It performs on par with traditional leaded solder, which is a remarkable feat. The only notable difference I've encountered is that the joints tend to look slightly duller, necessitating extra diligence to prevent cold joints. However, this minor trade-off is more than compensated for by the peace of mind that comes with using an environmentally friendly alternative without compromising on performance.The fact that it wicks effectively means that my soldering projects are efficient, with reliable connections that I can trust. Plus, knowing that it's safer for my employees and has a reduced impact on the environment makes it an easy choice. This solder has truly struck the perfect balance between performance, safety, and environmental responsibility, and I couldn't be more pleased with the results it delivers. It's become a staple in my soldering toolkit, and I wholeheartedly recommend it to anyone looking for a lead-free alternative that doesn't skimp on performance.

This solder makes very good joints on circuit boards and solder lugs. I prefer it to other no lead solder because it has superior wetting properties and makes joints that are secure and reliable. The "no clean" fluxes really don't need clean up either, making this a good choice for "getting the lead out".

After trying many different kinds of lead-free solder wire, I came across the Kester K100DL alloy. I gave it a try, and must say it is the best I have tried so far. After experimenting a little bit with the temperature setting, I found out that in my case the best temperature is between 330 and 340C (625 - 645F). At that temperature the solder flows like the leaded solders I am used to.However one word of caution; It does not want to reflow that nicely without adding a little bit of extra flux. So if you have to do some reworking of joints, add a tiny bit of flux before reheating the joints.

Works great. A little more stiff, tougher and more thermally conductive than 60/40.

I found the internal flux to be insufficent. Reworking gold contacts ended up with black-pads! Eww. Won't use again.If you must use it, BYO-flux.

Tried to go ROHS, but this stuff is tough to rework, and doesn't work well for repairs. Soldering iron needs to be significantly hotter, and thud damage to boards is likely. Avoid using this for repair work on vintage equipment. If you are building a new project, thus stuff is great. It certainly comes with peace of mind if you're worried about contamination and cleanup.

Quick wet time, flows like solder did before lead free. Nice shiny joints.