Soldering tips

I’ve only soldered one thing before today, header pins on an lcd.

Today I tried a few different things:

A small dc-Booster module which was hard because of the position of soldering the copper wires to the pcb pins already there.

Header pins on a Tft shield.

This time I had trouble because the solder wouldn’t come off the tip of the iron. So I had to do magic to rub the solder off on the board. And yes, I know I didn’t do a very good job.

But I’m here asking for advice.

And for your amusement, my pics

Flux, tinning and practice (practice, practice.)
Tin your tip, heat your joint and flow more solder; quick like.
You should practice, practice joining wires. That’s where we started, doing splices: the western union and the J splice.

what kinda solder are u using just wondering

also does it seem like your solder does not melt that easy? could be a temp problem I turned my soldering iron on a lower temp then I normally use and could not heat the work area up enough to have the solder flow to it not sure if thats your problem but had to test it do u have a temp gauge on your soldering iron ?

what solder are you using and what iron?

I say, let the soldering iron heat up for at least 3-4 minutes before using.... then put the iron on the pad, and then put the solder right where the pad and iron meet.... works for me.

Looks like the op is scared of getting it hot. The headers never got hot to pull the solder. And tin the copper wire then trim it down cause one of you pic has it touching the inductor.

Your key mistake is that you're putting solder on the iron, then expecting it to solder when you touch it to the workpiece. That will never work, because by the time you touch the iron to the workpiece, all the rosin flux in the solder (that's the "rosin core" in the rosin core solder you're hopefully using) is gone and so the surface oxides on the workpiece will prevent the solder from wetting.

You need to position the two things to be soldered, and then bring soldering iron into contact with the two pieces, and then touch the solder to the iron+things being soldered.

You can touch it up too - on that TFT shield, put soldering iron up to one of your crappy joints so the solder melts. Touch a fresh bit of solder to it - you only need a tiny bit, since there's already some there, you just want the rosin to do it's thing - and like magic the solder will flow and wet like it should.

You can also use flux (amazon/ebay "no clean gel flux", comes in a syringe, get some blunt needles for the syringes too), but I only recommend using this on more complex soldering jobs, like drag soldering surface mount parts - for things like pin headers, using rosin core solder correctly works fine.

Those joints are poor enough that I can't tell by looking at it if it's lead-free or not. Try to get the normal leaded (60/40 or 63/37) solder - it works much better.

Also, your solder joint to the DC/DC converter could potentially fail catastrophically, with sparks and flame. Look at the wire connected to the + - it's practically touching one of the pads on the inductor next to it! Don't have wires extending beyond the joint.

Finally - like on the DC/DC converter, see how there are little holes in the places you soldered the wires? The idea is you put the wire through the hole, then you can bend it over, so it stays in place and is easier to solder - as you might notice, soldering requires at least three hands, one of which is preferably fireproof. On that topic, don't bother with cheap "helping hand" things, they're so poorly made as to be useless (the hands don't stay put), get one of those mini vises that sits on the table.

Thanks all for your tips.

From what I got, my prox dure should not be:

  1. Touch the hot iron to the solder wire
  2. Bring hot iron with solder dab to the board and touch the parts to be soldered

I am heating the iron enough if enough is 2-3 minutes.

I did buy Flux that comes in a plastic container. But I don’t use it except when I start the job when I touch the hot iron tip to a dab of it. The reason was that my solder says it has Flux on it already.

Here are the pics of my iron and solder.

There are some very amateur YouTube videos on soldering but this one from Maplin is good: https://www.youtube.com/watch?v=f9RiXMf3z7A

Note how the two parts to be joined are briefly heated with the soldering iron before the solder is added. Header pins tend to take a little longer than component wires to heat up sufficiently.

There is certainly no need to use flux.

Marciokoko: Thanks all for your tips.

From what I got, my prox dure should not be:

  1. Touch the hot iron to the solder wire
  2. Bring hot iron with solder dab to the board and touch the parts to be soldered

I am heating the iron enough if enough is 2-3 minutes.

I did buy Flux that comes in a plastic container. But I don't use it except when I start the job when I touch the hot iron tip to a dab of it. The reason was that my solder says it has Flux on it already.

Here are the pics of my iron and solder.

Ok - the solder is proper - 60/40 or 63/37 is what you should use (lead-free solder needs a higher temperature, plus it can be tempermental to use - also, never mix leaded and unleaded solders when soldering).

That iron looks - well - large. For those kind of non-temp controlled irons, you want at max maybe 25 or 30 watts; ideally a 15 watt iron would be fine.

You definitely need to clean and tin your iron tip.

Use a brass or copper "sponge" (pan scouring pad - but don't ever use anything but copper or brass, and don't use anything with soap or other cleaning agents in it).

Start by heating the iron up (for these kinds of irons, I always let it sit for about 10-15 minutes - then I hold it near my lips - about 1-2 inches away - and "feel" the heat rising - to have an idea of when it is up to temp - once there, I touch some solder to the iron - when it wets the tip, and the rosin smokes, I know it is hot enough).

Then apply a liberal amount of solder (really, you're just wanting the flux to clean it) - then wipe the tip through the sponge to wipe off the solder and the crud. Apply more solder, wipe again - keep doing this until when you wipe it, it leaves behind a nice shiny silver tip. When you have that, your tip is tinned and ready to be used. You should always clean the tip of your iron and tin it before putting it away, and before first use next time you use it.

If you don't have a copper or brass sponge - you can use a damp (not wet) cellulose sponge instead (this is the "old school" way - but still works just as good); be careful when you do this, too - because sometimes the sponge can catch the solder, bend, and "fling" it - sometimes into your face. It is always a good idea to wear eye protection goggles or glasses when soldering - sometimes the rosin in the solder will "pop" and fling solder about - basically, get use to burning yourself - solder will pop and hit your hands, land on your legs if you are wearing shorts, and on your feet if you're not wearing socks - but always wear some kind of eye protection, because you don't want hot solder on your eyeball! Also - at some point you will likely knock your iron off the table. Whatever you do, don't try to catch it. You WILL NOT catch the right end. Unfortunately, saying this and doing it are two different things. For many of us, we had to learn the hard way - but, after that first time, you'll never do it again - trust me!

:D :D :D

Now - once you have your tip tinned, the way I have always done it (once the parts are in place, held right, etc) - is to put a small blob of solder on my tip (I personally prefer a "flat chisel" to a "conical" tip like you have), quickly bring that blob to where I need it, then apply the iron to the joint, let it heat up (less than a second), then bring in more solder quickly to "fill in" the joint. After you have practiced this a while (do it on twisted wires, or practice wires in a solderable perfboard) - it should take less than a second per joint to perform. Then - inspect your work (I prefer a lighted magnifying lamp for this part - I also have used a handheld inspection microscope - today, there are also those USB microscopes), and reflow the joints where needed.

In between joints - wait a bit - maybe a second or two - to let the iron re-heat - when you make a joint, your tip of the iron drops in temperature, so you need to let it "rest" in between to let it come back up to temperature for the next joint to be made properly.

Also - tin your wires before you solder them - this is very important; you need to tin everything you solder before you solder it. In fact - the wires on resistors, capacitors, etc (most parts - not all, though - mainly passives) are actually "pre-tinned" - but you may want to verify this (or just tin all your parts). Setup is everything in soldering; get all your parts and wires in place before you start (as many as possible) - per "layer" of the soldering process.

What I mean by "layer" is that you solder parts on a board in a specific order - that of shortest parts first (jumpers, horizontal passives, etc), then next shortest, and so on - leaving the "tallest" items last.

Never try to solder a part larger than your iron can handle - it will just suck the heat out of the iron, and make your joints (if you make any) look like what you have already posted. Basically - parts and everything act as "heat sinks" - so your iron has to be able to dump more heat than the part can dissipate in order to heat the joint up enough to solder it. For most things - up to TO-220 cases - your soldering iron will be fine. For anything larger (ie - TO-3 and similar), you will generally need either a larger iron, or use mechanical methods (sockets or such) to attach wires to the parts (generally, for these larger parts, you'll need to use mechanical fasteners anyhow, because wires or such will be so thick for larger currents that soldering isn't generally practical).

Note also the "heat sink" effect - if you are soldering a part and fear overheating it - if you have room, attach an alligator clip to the lead before the body of the component, and the heat will dissipate through the clip instead of the part. For some parts that are temperature sensitive - avoid soldering the pins "in a row" - start from one end, jump to the other, and alternate - until everything is soldered - to distribute the heat load. For really sensitive ICs - solder on a socket instead of the IC.

If you can get a handle on soldering with one of those irons like you have - you'll be prepared for anything (then, when you get your first temp-controlled soldering station - you'll feel like you won the lottery).

Hope these tips help - good luck!

:)

cr0sh: Start by heating the iron up (for these kinds of irons, I always let it sit for about 10-15 minutes - then I hold it near my lips - about 1-2 inches away - and "feel" the heat rising - to have an idea of when it is up to temp -

I'm amazed that you think it's necessary to wait 10-15 minutes for a soldering iron to heat up and even more amazed that you then hold it near your lips to check it's got hot.

My conventional (not temperature-controlled) soldering iron heats up to easily melt solder within 60 seconds. I would leave it another 10 seconds before cleaning it if necessary.

  1. Touch the hot iron to the solder wire
  2. Bring hot iron with solder dab to the board and touch the parts to be soldered

No. Wrong. You need to add solder with the soldering iron tip touching the wire and copper pad.

See EEVBlog soldering tutorials.

Archibald: I'm amazed that you think it's necessary to wait 10-15 minutes for a soldering iron to heat up and even more amazed that you then hold it near your lips to check it's got hot.

My conventional (not temperature-controlled) soldering iron heats up to easily melt solder within 60 seconds. I would leave it another 10 seconds before cleaning it if necessary.

Maybe things are different today - that old iron of mine is close to 25 years old; not that I use it much, as I now have a couple temp controlled stations. And...maybe my time was off, I've never really timed it - but I know it takes longer than a minute to come up to temp.

...and don't knock the lips, man! The lips are one of the most sensitive parts of the body to temperature changes. While I'll be the first to admit that my method is unconventional, and perhaps a tad dangerous, it has served me well when I use that iron.

Many times, though, between feeling around the spring iron stand coil, and looking to see residual rosin smoke drifting off the tip - that let's me know it is hot enough.

Marciokoko:
Thanks all for your tips.

I personally would like an update on if u fixed the problem.And what it was when u get to it.

Ok i fixed the copper wire to board joint a little...

But the shield i still have problems with.

I cant get the solder to look triangular. I just get these blobs.

I cant upload pictures anymore...

Marciokoko:
But the shield i still have problems with.

The header pins require more heat to get up to the necessary solder-melting temperature. Try to rest the tip of your soldering iron against the side of the header (I appreciate there is very little of the header above the printed circuit board). Try putting a tiny amount of solder on the tip of your iron before you bring the iron to the side of the header so you get more thermal contact between the tip of your iron and the header. I don’t like pointed conical or small-diameter soldering iron bits; you don’t get good heat transfer. I much prefer using a soldering iron with a “chisel” tip, say 2.3mm diameter

Marciokoko:
Ok i fixed the copper wire to board joint a little…

But the shield i still have problems with.

I cant get the solder to look triangular. I just get these blobs.

I cant upload pictures anymore…

Upload the pictures to tinypic or other free photo hosting service and click the insert image button above - there are literally hundreds of free photo hosting sites.

Are you following our instructions, particularly that you must touch the solder to the iron while the iron is in contact with the thing you are soldering - otherwise you will never get a good joint, just blobs that often don’t make an electrical connection.

Attaching images on these forums is sub-optimal anyway, because you can’t view them without saving them to your computer.

OK here is my first attempt:

https://flic.kr/p/ytKLHV

Here is v2:

https://flic.kr/p/xw9Fot

it looks like the pads and pins aren’t getting hot enough…

OK I made this:

https://flic.kr/p/ytNMGx

And:

https://flic.kr/p/ytNMED