I posted previously about some drivers I purchased for a couple of convoy s2+ sst-40 flashlights. The first one I purchased from China and it had some quality control issues so I purchased one from. Mountain electronics and it was excellent. I gifted one light to a friend and decided to grab another driver and a beefed up switch from mountain electronics. I put it all together and it was working fine but the little plastic bow tie piece that covers the electrodes wasn’t centered so I took the pill back out and my joint on the positive terminal broke loose. On all my other mods I was using a soldering iron with dual temperatures on the low setting and it had a very fine tip. Well my tools got stolen so I asked my wife to grab me another one from radio shack. Turns out they had went out of business so she got one from I believe Ace hardware or something. Anyways this one has a much fatter tip and seems to get extremely hot. It came with solder that seems to have a lot of Flux and it gums up the tip of the iron really badly. Also I am having a hard time not globbing way too much solder from such small components. I kept having trouble getting a joint to stick afterwards and am pretty sure I shorted somewhere and fried the driver. First it was stuck on high then I finaggled more and heard a sound that was I’m pretty sure sometimes frying. Could anyone recommend a brand of Iron and a brand of solder that they use to mod? It’s kind of embarrassing coming on here and telling you guys that I’m having issues with something that should be the simplest mod other than a drop in. I have never had a problem like this before but it is what it is. Thanks
This is the best solder I have ever used. RadioShack SnPbAg 62/36/2 Silver-Bearing Rosin-Core Solder, 0.015" Dia?
Radio shack has a few stores still open but they have turned mostly to internet sales. That solder is thin for small work and is silver bearing for a higher conductivity with a low eutectic temp.
Since the “Recommend soldering iron” question pops up quite often, I’ll point you to this recent thread for a soldering iron.
soldering iron recommendation for simple work
Thank you so much. I’m embarrassed at having an issue with something so simple. I’ve done much more complex mods (still far from anything other than amateur) but the only factor that changed has been the soldering iron and solder. I really do appreciate your input.
I also had some trouble with soldering in the beginning. I now know that if the solder joint is nice and shiny the temp was nice and high.
No need to be embarrassed buddy
Soldering irons can be finicky at times
I destroyed a really nice driver from lexel on here
I really wanted that driver also , I tried to solder a spring in and a lot of the components decided to walk away from there home place
I’ve now fixed my iron
I have a massive few kg reel of 20 year old solder that’s loverly , nice combo of lead and silver
Nice! Hopefully I will get a nice setup figured out and get comfortable with it.
Yup, def no need to be embarrased for seeking out knowledge, quite the opposite.
Sounds like you need to get to grips with soldering basics, which is all about applying the right amount of heat to the right components in the right place for the right amount of time 
Heat is bad for components but needed to melt the solder in order to get it to flow to where it’s needed, so the aim to use the least amount of heat possible to control the solder.
A temperature controlled iron is a must, as is understanding which tip to use and how to maintain the tip, a dirty tip blocks heat which has an adverse effect when trying to control heat flow.
Solder composition is probably more relevant than who makes it. The two main advertised solder types are leaded and lead-free. Leaded is easier to work with but breathing lead-laced fumes (amongst other things) is largely undesirable which is where lead-free comes in, but it’s harder to work with as it melts at a higher temperature.
For home hobbyists the common composition for leaded solder is Sn63Pb37 which translates as: Sn=chemical symbol for tin — 63=percentage of Sn in the solder — Pb=chemical symbol for lead — 37=percentage of Pb in the solder. The 63/37 ratio is eutectic, which basically means the sweet spot for the mixture, and has a melting point of 183 degC.
You can also get sn60pb40 (60% tin, 40% lead) which i think is slightly cheaper to produce with the trade-off being a slightly higher melting point of 188 degC, and sn62pb36ag02 (62% tin, 36% lead, 2% silver) but i can’t remember the reason for adding silver.
Lead-free solder has melting point around 220 degC, which means having to put a lot more heat into components when working with them, a big trade off.
The above mentioned solder types are common for home use, in industry there are a whole host of compositions designed to meet specific criteria.
Flux helps solder to flow thus reducing the amount of heat needed. It is normally contained in solder wire you buy but gets used up in the process of soldering which is why fresh solder seems to melt more easily than pre-flowed solder (i.e. and exising solder joint). You can buy flux separately to add to existing solder joints to help it flow more easily but while i muddle through with what i’ve got i’m not knowledgable enough to advise on the different types or how to use it effectively, that’s definitely something i have to learn! (And i’m not embarrased to know it 
)
Have a read through here for some more info: Soldering iron tips, how to solder SMD without ruining the PCB and come back on either thread with any questions you have
Again, I have to add another thanks. All this information is so invaluable to me. The thing where you said selective temp is a must had to have been why I never had a problem until my new setup. It seems to get much hotter plus it has huge tips that are interchangeable but were all so robust that I couldn’t use a conservative amount of solder (at least with my experience level). I totally get Flux and lead free solder as a pipe fitter but intricate electronics are on a whole different level. All of this info you have given is golden, along with the other input. I love this site as a resource, it’s priceless. I must have gotten lucky with my first setup that worked great but I had help picking it out by someone who knew what I needed for the job. I do want to get another iron like I had before when I had none of these problems but with all of the suggested threads and info I learned I think I can make the right choice. You guys rock. Thanks.
Good link Marc E! Soldering flux is essential for good soldering. Soldering without it can get very messy. The flux helps makes the solder adhere and keep it liquid. Whenever I’m soldering and the solder seems to get uncooperative, I add a little more flux and that makes a big improvement.
Another thing Onthebrightside is to keep the soldering iron tip clean. Oxidation on the tip makes it hard to solder. I use a brass tip cleaner with rosin flux paste to keep it clean. I’m constantly cleaning the tip and adding new solder and flux when I solder.
Hey, I know that this is an old thread but I had to come back and thank you so much for the advice on the solder and all of the advice from everyone else here. I purchased that exact solder that you recommended and also a soldering iron station that has clips to hold the part that you’re working on, a ceramic heating element with multiple tips (one is an extremely pointy one just how I like it) and it has a digital readout that tells you the temperature and can be set at any temperature between 174 and 900 degrees Fahrenheit. Also you guys were one hundred percent correct that my other iron wasn’t getting hot enough. I thought it was getting too hot, boy was I wrong. The best way I can describe everything is now when I solder it feels the same as when you play a video game and use cheat codes. I fixed a whole bunch of stuff and my confidence with soldering is through the roof. Thank you everyone for your help. It made an unfathomable difference and was the best advice I’ve ever been given. Cheers.