I can't get them to stick. Any tips? Rosin core solder and 25 watt iron
I can't get them to stick. Any tips? Rosin core solder and 25 watt iron
Go get a much smaller lower watt iron with a fine tip. Bigger is not better in the world of soldering. You want to match the iron size and wattage to the size of what you are working on.
Keep the iron tip clean and (most important) - tin the tip!
Just earlier this year I did my first circuit board soldering. It was repair for a dead Prius Speedometer. This $14 purchase from Amazon got the job done.
Good tips. Gotta be clean. Those wires look a tad beefy for that board.
Are you soldering on your wife's tablecloth? That can be dangerous.
Is the solder lead free? If so, it wants a higher temp.
Test your solder compatibility: the board might be lead free ( good chance in today's world) needing high temp to wet out and your solder might be lead. If so, then your temp might be to low to reflow the tinned wire on to the board pad.
If the wire takes the solder to tin the wire, AND the pad takes the same solder when you try to add a solder bump tot the board, then it should easily solder on to the pad.
It looks like you are soldering to a pad rather than a through-hole. Add a dap of solder to the board pad.
That is a big wire to be soldering to a small pad.
Not a fan of rosin cored wire, prefer to add my own flux to the job then clean it off after.
If you are soldering the wire tip to the pad, tin the wire and then using a good set of nips, cut the tinned wire square at the end and solder it perpendicular to the board.
(1) Lead solder is way easier to work with than the lead-free stuff. Note that lead is bad for you and if you're doing regular soldering with lead, you need good ventilation. It's hard to find in retail stores, but trivial to order online. For the sort of thing you're doing, you want something like this 0.5mm 5-core 60/40 tin/lead solder. Yes, it's expensive, but it makes a huge difference over the cheap stuff.
(2) Make sure you're heating the wire and pad, not the solder directly so that you're getting it hot enough with no cold joints.
(3) Looks like smaller wires for what you're trying to do there would make your life easier as well.
In addition to everything else that's been said, make sure you have a good mechanical connection before you solder. The wire should be through the hole and stable; then hit the wire and the pad with the iron to get them hot, and touch the solder to the wire and pad (not the iron). When the pad and wire are hot enough, they will melt and wick the solder. Make sure the joint doesn't shift or move until the solder had solidified. A good joint will be shiny and cone shaped; if it's dull grey or ball shaped try again.
Tech Tip: if you really want old school lead/tin solder, craft stores. If they have a section for stained glass windows, they have leaded solder.
If this is just a solder pad and not a through hole you have too much wire exposed. Only strip the size of the pad + a tiny bit extra. Tin both the pad and the wire with solder and hold the wire close to heat up the pad and wire at the same time and "smoosh" them together, let flow, and remove heat. Make sure nothing moves during cooling and the joint will be stronger than the pad to board connection.
Agreed on the suggestions of making sure you have the right tip, heat, dia and type of solder.
Alright. I seem to have all the wrong stuff then. I'll drop by the hardware store and probably the craft store and get what you guys are suggesting. I can use smaller gauge wire, that was the smallest wire I had laying around so I'll look for that too.
Its a garage door opener I'm trying to solder a remote switch on to install on the handlebar of my bike. I have everything mocked up for testing except getting those wire attached to the board of the remote . Appreciate it guys. I will update.
Edit: yes that is my wife's tablecloth. I already burned it in one spot. Don't tell her.
A bit frustrated my local stores didn't have what I was looking for. Off to amazon or ebay for the rest.
I've worked a couple jobs that required extensive soldering; We basically only used lead free solder, and it worked great. There's almost no reason to be using lead in this day an age, unless working on legacy boards that were put together with leaded solder. Lead is cumulative over your life, and it never leaves, lead solder is not so much better to be worth the exposure (unless the part's going into space, look up tin whiskers). Due to RoHS, almost everything is designed to use non-leaded solder.
The biggest difference with lead free solder in my experience (and that hasn't been mentioned here) is flux: It will make your life so much better, trust me. The flux makes the solder act like it's got some surface tension basically, so it will flow into joints and creat the nice looking good joints you need. Working with SMT parts and a good lead free solder paste beats doing through hole work any day, double true for rework. With wire solder, there's flux in it, but if it's hot for a while the flux will burn off -- this is why you always start with a clean iron, so that you are adding new solder that has flux in it. Having a tube of flux around gives flexibility because it allows you to add flux without adding more solder (especially important for rework).
The points about heating the pad and not just the wire are spot one, as is the need for a mechanical connection before soldering: it's possible to solder a wire to a pad like this (I used to do this on aluminum PCBs, a major PITA), but you have to hold the wire against the board before, during, and after heating it. My procedure would be: Add a mount of solder to the pad, almost the height of the wire; tin the wire; grab the wire with some pliers (to avoid burns), and hold it against the solder on the pad lightly pressing down; apply soldering iron on top of the tinned wire until it all melts together. If you're not getting fusion, then your iron is too small (looking at the parts this is unlikely), you're not being patient enough, the tip of the iron is corroded or not properly tinned, or you forgot to plug it in. From the pictures, it looks like you may be having some tip issues (the tinned part of the wires is chunky and spiky; there should be less solder and it should be smooth, basically coating the strands and gluing them together into one piece), so I'd start there. An unhappy tip can prevent enough heat transfer that it feels like the iron is not powerful enough. Tips are cheap, may as well try a new one.
To protect the table cloth, a small scrap of plywood will do wonders. It also helps with clean up of the stray bits of solder that hop off when using the sponge.
After you've solder the wires, I'd reccomed glue them down to the board for strain relief. One good tug will rip that pad right out of the board, which will make for a significantly more fun repair job.
MrRobogoat (Forum Supporter) said:I've worked a couple jobs that required extensive soldering; We basically only used lead free solder, and it worked great. There's almost no reason to be using lead in this day an age, unless working on legacy boards that were put together with leaded solder. Lead is cumulative over your life, and it never leaves, lead solder is not so much better to be worth the exposure (unless the part's going into space, look up tin whiskers). Due to RoHS, almost everything is designed to use non-leaded solder.
The biggest difference with lead free solder in my experience (and that hasn't been mentioned here) is flux: It will make your life so much better, trust me. The flux makes the solder act like it's got some surface tension basically, so it will flow into joints and creat the nice looking good joints you need. Working with SMT parts and a good lead free solder paste beats doing through hole work any day, double true for rework. With wire solder, there's flux in it, but if it's hot for a while the flux will burn off -- this is why you always start with a clean iron, so that you are adding new solder that has flux in it. Having a tube of flux around gives flexibility because it allows you to add flux without adding more solder (especially important for rework).
The points about heating the pad and not just the wire are spot one, as is the need for a mechanical connection before soldering: it's possible to solder a wire to a pad like this (I used to do this on aluminum PCBs, a major PITA), but you have to hold the wire against the board before, during, and after heating it. My procedure would be: Add a mount of solder to the pad, almost the height of the wire; tin the wire; grab the wire with some pliers (to avoid burns), and hold it against the solder on the pad lightly pressing down; apply soldering iron on top of the tinned wire until it all melts together. If you're not getting fusion, then your iron is too small (looking at the parts this is unlikely), you're not being patient enough, the tip of the iron is corroded or not properly tinned, or you forgot to plug it in. From the pictures, it looks like you may be having some tip issues (the tinned part of the wires is chunky and spiky; there should be less solder and it should be smooth, basically coating the strands and gluing them together into one piece), so I'd start there. An unhappy tip can prevent enough heat transfer that it feels like the iron is not powerful enough. Tips are cheap, may as well try a new one.
To protect the table cloth, a small scrap of plywood will do wonders. It also helps with clean up of the stray bits of solder that hop off when using the sponge.
After you've solder the wires, I'd reccomed glue them down to the board for strain relief. One good tug will rip that pad right out of the board, which will make for a significantly more fun repair job.
This advice is spot on. I suspect that the problem that you're having is a mix of leaded and lead free solder. The fluxes are incompatible so you really need to figure out what the board is and use something compatible.
Using wick to get rid of all the solder and clean with IPA will eliminate that issue as well.
Paul_VR6 (Forum Supporter) said:Using wick to get rid of all the solder and clean with IPA will eliminate that issue as well.
A much better use than drinking it. :)
Robogoat is spot on. You cannot rely on a solder joint for electrical and mechanical connection. Use a solid 30AWG jumper wire, and glue it down. What you did may work a few times but the vibration an lack of strain relief will kill it.
In reply to MrRobogoat (Forum Supporter) :
Perfect. I shall do this. All the things I ordered will be here by the third. I definitely needed a new tip but I went and bought a whole new iron anyway. When I glue them down afterward, will superglue work or is there a better adhesive to use?
Just the tip.
In reply to gunner (Forum Supporter) :
...And only for a second, mind! Yeah, neither of those look exactly what I'd call "happy". The top one looks too far gone to my eyes, I'd go ahead and replace that; the bottom might be saveable with some scrubbing. Speaking of, to prevent that build up a regular quick wipe on a damp (not moist!) sponge followed by some fresh solder will do wonders for the tip, and your solder joints. All but the cheapest soldering iron stands come with a sponge holder for this purpose. I tend to wipe and tin my iron any time I'm setting it down or picking it up, the exception being if I'm working really fast I will skip the wipe when I put it down. It's just one of those habits that makes the actual work go smoother even if it feels slow at first. There's also brass tip cleaners, but I find them a bit more aggressive and liable to fling hot solder at you as the brass springs back. They are good for heavier duty cleaning, however.
Re: Glue question: Hot glue is what I would go for in your situation if you have it available, the nice thing is that you can clean it off pretty easily if you need to remove the wire. There are some epoxy like special products, but that's not really economical. I'd avoid superglue for two reasons: It's thin, something that builds up a bit will spread the force from the wire over a larger bond area; the second reason is that superglue when heated releases toxic gasses, a lab at RPI had to be closed and a student ended up in the hospital due to this issue a few years back. I like to assume that I'll be the next guy, so I try not to leave surprises like that.
Hope this helps!
Agreed both look pretty E36 M3ty, in a pinch you can just grind them down but you will lose any coating that may have been left and you will have to keep abrasive cleaning until you retire it. Ditto on the sponge, I just use cut down cheap kitchen sponges for this. A barely damp paper towel can work in a pinch. I clean both before tinning and after soldering.
On the glue I usually use a soft silicone and let it cure for a day but hot glue will work if it's not going to rattle around or get pulled on. You will want to etch the surface you are trying to adhere to a little bit to let it grab (unless a chemical bond is likely)
That tip still looks terrible and won't transfer heat. Hit it with some steel wool to get the scale off, then tin it with solder or tip tinning paste (which I really like). It needs to be shiny silver.
Sorry for the slow response. That tip is the same tip for the two photos. its about 30 years old and I cant find the same size to replace it. 3.75mm x 75mm. I have found 3.6mm x 67mm on amazon. Will that work? was wondering if that shorter piece would reach the heating element or not because I don't really know how they transfer heat. At any rate I bought a cordless Weller unit, model wps18mp since I have been fighting the cord for my whole life, since all my irons have always had cords, to replace it with. I still want to get a new tip for the old thing so it's still a useful piece.
Edit: Well poke me in the eye! it's not cordless. eh, whatever. I'm keeping it.
I got it done and installed tonight. I had intended to take photos but everything was going so smoothly it all just flowed. Pun intended. I'm returning the Weller after buying an honest to god welding station, it is also Chinese made but since it only had 3 words of English in the whole instruction manual I figured it was built much better. I used 28 gauge two conductor shielded headphone wire with the board then connected that to a waterproof automotive grade connector. I applied strain relief at the back of the remote case with a dollop of hot glue. connecting 22 gauge speaker wire to the other automotive connector and the switch on the other end. I tested it at each stage and its solid. For installation on the bike it uses a single point connector of what seems like stainless steel with the switch in a hole on the other end about an inch and a half away. Its supposedly a waterproof switch. I routed the wire through with the factory loom and located the remote under the seat in front of the battery. I only had to remove the front seat fastener and the two front fasteners for the fuel tank and rotate it upward. It's the cleanest install I have ever done.
Glad you got it sorted!
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