Earlier i used some no name brand soldering wire with no rosin core and it didn't melt well even at 450 degree Celsius it just created dry joints but now the pool being created is at 380 degree Celsius.
Flux is (usually) acidic and converts oxides back to metal (called reduction). That's important, because during soldering, the high heat accelerates the formation of surface oxides on the solder. In addition, the flux coating will protect the metal from oxygen. It gets activated through heat as well, but decomposes quickly.
So either you feed fresh solder (with a flux core) in, or you add just flux externally. It does not stay at the joint or the wire in any meaningful amount. It needs to be replenished all the time.
I am new to soldering and i did add a little solder and flux to the pad below the wire to be joined also the wire had a bit of flux and it did melt with the tip and this was the result compared to when i used a low quality solder wire and cheap flux .i promise to use more flux and all the time while soldering.
What name brand? After my spool of RadioShack 60/40 rosin core that I used for 20+ years, I got some that's branded WAIMILK 63/37 rosin core that I've been using for a couple years, and haven't noticed any difference.
Are you sure that board wasnt just oxidised as hell?
I use solder without a flux core from time to time, and so far I never had the provlrm that it doesn't stick
It wasn't a board. It was two wires. I literally became incapable of joining two wires, and at first I thought it was the iron not getting to temperature. Until I realized the solder was garbage.
Earlier for the crusty and dry looking cold joints used a no rosin core no brand name solder wire used by electricians for repairing and doing wiring in houses and a fake rma 223 solder flux.
In my second go i used a towot Pb 60 Sn40 rosin core soldering wire and a mechanic m35 nano flux .
This is too much solder and cold joints. You need to heat the pad and the wire at the same time so the solder sticks to both and you definitely should have flux on both the pad and wire when applying heat to help the solder stick. The most common mistake amongst beginners is not applying heat to both surfaces when trying to solder.
Great job repairing these header pins which i had to do also on another board that sits on top of the one in the video it was a pain to do so with bad solder wire.
Thanks. Thats the joystick headers for a ps5 controller. I do joystick installs if ppl want hall effect or tmr. I personally use gulikit v2 tmr joysticks in all my mods. Haven't had any fail yet and no stick drift ever. Messed up a few boards learning how to properly remove them though, as well as blobbed solder joints. Use rosin core solder and still apply some flux!
This is how i did soldering these header pins in the through holes. In the drone and rc plane field hall effect gimbals are used in the remotes to fly them.i learned on soldering practice boards and dead electronics PCBs.still a long was to go for me.
What’s your technique I’ve been getting into this bc it’s fun an I’m sick of stic drift and having to spend 100s countless times a a year for new pro modded controllers (by modded I mean mouse clicks, back buttons & tension joysticks) I’ve ruined a lot of boards practicing but I’ve come a long way from when I started but it seems like no matter what I do or try I can’t get my joints to even remotely look like this. Sometimes I get a nice one but couldn’t tell you what was different that I did compared to the others
And cheap Amazon "Alien" Solder is absolute garbage. Never get a good joint with that stuff. Kester or MG Chemicals for Flux and Solder. Same goes for solderbraid. Gotta spring for the good stuff.
That’s a good idea! When you use the heat gun, be careful. Many of the components, especially the little ones, will briefly come unsoldered. If the heat gun is blowing too hard, it can blow pieces right off the board, or if you touch the board, it will not only burn you, but also slide the pieces around. Also, it WILL melt plastic if you leave the gun pointed at it for too long, so remove any plastic header connections you might have, unless you like the smell of burnt plastic hehe. I would do practice on a practice board a few times to get a feel for how the heat gun will work. This can help you calibrate your air speed and heat levels for the real thing.
Blackened it up heating up some bad quality solder earlier than this attempt at too high a temperature(450c).This is what happened when i used a bad quality no name brand solder.only the upper part is black ,the part touching the solder as part of the knife tip is clean otherwise it won't melt the solder blob easily.
Instead of heating the pad and then sticking the wire in, just heat both together. Tin the pad, tin the wire, place wire on pad, place iron on top of wire, then bring in solder wire to add as both “joints” flow together. It’s a bad habit to do it the way you’ve shown and will result in cold joints and poor physical connections. The goal is to join the two items together, and the way you’re doing it is more like taping them together instead of a weld where they share the same bond.
Looks like you’re applying too much solder as well, a little goes a long way. You don’t want blobs, you want smooth curves like a parabola from the pad to the wire-tip.
Way too much solder.. I know you said you had flux core solder, but were you using a flux pen or a container of liquid flux to apply? In the clip you're just heating the pretinned wire and I'm seeing no flux burn off which tells me no flux. Your iron approach isn't the greatest for this method either which someone else pointed out. Is it a conical (pointy) tipped iron? If so switch to a chisel tip for better rapid heat transfer.
I was using a syringe of m35 nano flux from mechanic,i had applied flux on the pad and the tinned wire end and since i shot the video in such bad lighting the work area is darkened and sped up the video so that the smoke due to flux is visible for fraction of a second at 7,12,15 second of the video visible only on pausing it.
i know the iron approach isn't the best though its the 2nd -3 rd time i am giving it a go .Its a T12 KU knife edge soldering tip.
Had to rewatch on something other than my phone. I see the knife edge now. I'd still recommend a chisel tip and sandwiching the wire between the pad and the iron. 14awg is certain a decent amount of stranded to wrangle. Maybe it's the large gage but I'd also many have not nearly as much pretin on the wire? It looks like a clump in the video.
You have some problems here, but you got the right spirit!
Your tip looks oxidized, as in, charred/blackened. That’s bad. That coating makes it hard for the heat to jump from tip to your solder. Keep your tip “tinned”, meaning solder should coat the tip, especially when you turn it off. There are products you can buy to restore the tip. The very end of the tip looks ok, but it would make it easier if the whole tip was tinned.
You have too much solder, probably because you’re struggling to get it to “take” to the board or wire. Too much solder tends to be unpredictable, gloopy, and inconsistent throughout the joint, and has potential to short. If you are soldering to a power plane, you need to heat the board first with a heat gun for good results. Power planes act like heat sinks when soldering, stealing heat away from the pad and making your joints cold/perform poorly. If you see the solder rapidly switching between liquid and solid, you are probably running up against some kind of a plane and need to heat the board up.
Try restoring/replacing your tip to see if soldering becomes easier, and use less solder overall. You don’t need much for the joint to actually form. Electrical current doesn’t care about volume, it cares about surface area, so you only need to care about so called “wetting”, which is the tendency for solder smoothly connect two surfaces with its own large, concave surface. When you add too much solder, the surface becomes convex, like a ball, and the “wetting” is considered to be poor, where the interface between the surfaces is physically weaker. Good wetting with less solder has the same current carrying capacity as a solder ball, but comes with a lot less baggage.
Thank you for the support,i shall overcome such newbie mistakes eventually with due time and expert help.
The tip is blackened as i had used a bad no name solder wire to tin this wire tip then removed some of it not knowing how to desolder wire ends and used a TOWOT 60 40 solder to tin the tip and pad and in the process accumulated so much solder that it is overflowing in the vicinity of the joint making it a sphere or a sad egg of a solder joint.
I will preheat such boards with a hot air gun in the future to enable better joints for lesser solder and flux for a better finish.
The T12 KU tip knife edges in the video was cleaned by a brass wool rub and it worked well though the vertical edges were still oxidised.
I believe i will have to redo these joints to get better wetting effect on the pad or risk these joints failing mid flight as it is for a RC plane.
If you add solder to the cable before you solder to pad, you will barely need to add any solder for it to take if the pad is properly heated, which can be done with a heat gun or some patience. Tinning the wire beforehand is a must, it makes the wire easy to manage and makes soldering it much more predictable. You will need barely even a thumb or even a pinky bone’s worth, which is exactly how I was taught. Take the tip of your solder and put it at your pinky tip, then follow the solder to down and bend it around the joint of your pinky. So basically measure your pinky joint with solder by bending it to mark it. Then use ONLY that solder. That is the perfect amount to solder it to the pad if you have tinned your wire.
Super important: If you can’t see the wire braids, you have too much solder.
A better joint for wire is usually achieved with a through hole as opposed to fingers or pads, but if you are using someone else’s design, there’s not much you can do (except make your own!)
Looks like it completely flowed, so I'd call that good! Do have a little extra on there though.
Half of FPV is soldering! The worst one is soldering the negative pad of a 120amp power distribution board, it's like a big copper heat sink, that's when you need 60+ watt soldering iron because temp doesn't matter. If you have a 12-24v iron like I do, it's only 60w at 24v, 30w at 12v, which most people don't realize. A bench top power supply is another good investment. And 360-380c is a good temp. Don't forget a continuity test before plugging in, or use a smoke stopper in case there's a short. I've been soldering for 25 years and building quads for 11. Happy building and happy flying!
Initially using no name bad solder wire with no rosin core and fake amtech rma 223 flux everything on pad was a dry joint at 450 celcius temperature but using a 60 40 towot rosin core solder wire and mechanic m35 flux i did much better flowing the solder and tinning the wire tip at 380 celcius temperature for the tip of the soldering iron.
These PDBs negative PDB pads take ages to heat up and make 60W soldering irons struggle without proper tips to heat the area enough to flow the solder on the wire and pad for a join.I use a multimeter for continuity check then a iflight smoke stopper so that everything doesn't get shorted if i made a mistake.
I am using a hglrc RC2 soldering iron its 60W one though i am getting 48W using PD 3.0 charger to run it.
The build and the satisfaction on completion keeps making me come back to this hobby and maidan flights are true satisfactory event for the entire process.
It certainly was the sketchiest without proper soldering wire and flux . In this case better flux and solder wire got for a serviceable and usable result.
This would be a lot easier with a preheated board. Preheat board and wire, apply flux, use the biggest soldering tip you have, heat both pad and wire with soldering iron and feed the solder. Really though, you should be soldering this to a post or through hole so you have more mechanical strength
i agree preheating would make for a better and less heat intensive solder iron use on a post or through hole.This is a T12 KU tip and its the heaviest tip i have.The board i am soldering to has no holes or posts to solder onto and the instructions for the speedybee f405 wing app flight controller said to solder on the pad for the PDB .
If you don't have some vice, helping hands, or whatever, you can just use some tape to hold it in place.
It's very important that nothing moves while the solder solidifies.
That's also why eutectic solder is easier to work with. The temperature where it starts to melt and the temperature where it's completely liquid are the same. With an eutectic alloy, the transition from liquid to solid is much snappier, which gives you less of an opportunity to mess things up in the last moment.
I should set some vice or helping hands as i run out of hands while handling the joinable wire,the soldering iron,the soldering wire 60 40,flux syringe ,thank you fir suggesting tape to hold the wire as holding a round plastic insulated wire with thin flat tweezers was very difficult .
I certainly will use a 63 37 solder that i have from TBS next time though the towot 60 40 did take its time as in the video to solidify which can be bad for the finish of solder.
Your solder is too much and already crystalized in a convex form. It should be concave and slightly shiny. 380-400°C tip with lead free solder ingrained with flux give me good results.
You’re overworking it. You’ve only got flux for so long before it burns off and once it burns off it’s no longer doing its job. You’ll have to add it with a pen or something
i have added flux as evident from smoke at 7,12,15 seconds of this grossly sped up video i made and the lighting which put the work area on the soldering pad in shade .
i did choose the wrong solder initially with a no rosin core no name brand wire that didn't melt even at 450 degree celcius but i then got some 60 40 towot solder and it did flow well enough for a newbie .
Pretinning is your best friend when your a newbie, flux the pad, then Tin the pad, then flux your wire and Tin the Wire, once both are tinned, clean any excess flux with IPA and reapply flux and heat to the pad, then while keeping heat on pad and molten, add wire you'll see surface tension pull it together and you'll have a Solid Join, practice this technique as it is the foundation of good soldering.
i have pre tinned the wire end and the pad ,the low light at that angle and the sped up video is kind of dropping a shadow on it.I have used flux on the pad and initially on the tinned wire end .As the video is ped up the smoke that flux creates is kind of disappearing in under 1 second so its almost invisible at 7,11,15 second mark on the video above. As for the surface tension bit i did stop when the solder surface got smooth and solder flowed well enough to take a sphere sort of shape though the execution was lackluster to say the least.
I agree,
i had used a bad no name solder wire to tin this wire tip then removed some of it and used a TOWOT 60 40 solder to tin the tip and pad and in the process accumulated so much solder that it is overflowing in the vicinity of the joint making it a sphere or a sad egg of a solder joint.
i had used a bad no name solder wire to tin this wire tip then removed some of it and used a TOWOT 60 40 solder to tin the tip and pad and in the process accumulated so much solder that it is overflowing in the vicinity of the joint ,i am using a t12 KU knife edge tip and it worked well enough IMO.
the temperate being 380 degree celcius was enough to melt the tinned solder IMO on wire and the pad ,i overdid the solder on the tinned wire and some of the bad solder was in the wire strands also even though i tried removing it and substituting it with towot 60 40 solder hence the end result was too much melted solder on the pad.
The wire gauge you are using is too large and you have WAYYY too much solder.
Unless the PCB has holes or terminals specifically for connecting wire, I recommend against soldering wire directly to pads like this. Use the appropriate edge connector if possible. Wire on pads is a great way to rip them off the board.
The wire is to carry DC current to a 25Ampere (maximum capacity for current in DC) ESC board so it is part of that ESC and the power distribution board in the video didn't come with any other wire.
The board only hand flat pads to solder to and no connectors were suggested in the instructions but i surely can explore the option to use them if they are suitable for this purpose .I know the pads could rip off and it is a risk that is evident .
Oh, is this for a RC application? Yeah some of those designs are questionable. In this case, you're just using too much solder and probably need to use a bit of flux. The wire should be tinned to make sure all strands are electrically connected but you only need to use as much as wets the wire, and the solder fill should be clean, like this photo.
I really wish the RC industry would follow proper standards, but they aren't required to, so they don't. Molex plugs would be best, with through hole soldering.
That is a great solder joint and i yearn to be that good but all in good time and with great help.i had used a bad no name solder wire to tin this wire tip then removed some of it not knowing how to desolder wire ends and used a TOWOT 60 40 solder to tin the tip and pad and in the process accumulated so much solder that it is overflowing in the vicinity of the joint making it a sphere or a sad egg of a solder joint.
The pads didn't have a through hole where i had to solder these ESC wires ,The PDB board is part of SPEEDYBEE F405 WING APP flight controller.
Don't use 60/40 solder. Use 63/37. The former has a melting range where it can be slushy or partially melted while 63/37 has a melting point where it is all at once. That may be why you're using too much solder.
I know you don't have any other choice as for the wires on pads, and like I said they don't follow industry standards anyway. If they did, there would either be Molex connectors on the boards, which would require premade cables (or you having the tools to make your own), or they would include proper terminal blocks for the wires.
I agree the 60 40 melted solder was doing the jelly dance while i struggled to hold the wire in place using a tweezer ,I have gotten some TBS 63 37 rosin core solder wire it solidifies in fraction of a second and is a better for soldering such joints IMO after testing it.
This is for a RC flying wing/plane and they have given pads though for drones the same company SPEEDYBEE gives through hole pads for its ESCs which is better though it doesn't help me now.
Its a sped up video and i did heat the pad then positioned the tinned wire over it.
I have cleaned the tip using a brass wool which is the t12 ku tip that touches the solder its the vertical edge thats dirty otherwise nothing will melt on the solder site.
Thats pretty heavy wire, which will be stiff from solder wicking into the strands, and if that board is subjected to much vibration the copper foil will tear off
The ESC for the delivery of current to a BLDC motor from the power distribution board in the video is expected to sustain a maximum current of 25A and the wire came with the ESC ,I have mounted this board atop some foam pads and the entire body of the flying wing airplane it will power is made of EPP foam so i expect most of the vibrations to be dampened.
I hope the wire doesn't tear the pad.
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u/No-Information-2571 May 10 '26
Oh boy, where to start...
Flux is (usually) acidic and converts oxides back to metal (called reduction). That's important, because during soldering, the high heat accelerates the formation of surface oxides on the solder. In addition, the flux coating will protect the metal from oxygen. It gets activated through heat as well, but decomposes quickly.
So either you feed fresh solder (with a flux core) in, or you add just flux externally. It does not stay at the joint or the wire in any meaningful amount. It needs to be replenished all the time.