Soldering iron help

[Protolisk]

I got a Dick Smith electronics 40w soldering iron on the Christmas holidays. Its better than the one I had before but when I try to desolder some stuff on an old xbox controller it takes ages to melt the solder. Like 10-20 secs. Then when I take away the iron to suck it up with a desoldering pump (also from dick smith) it solidifies almost straight away. I cant even move my pump from a mm away to over the top of the joint before it goes hard.

When I melt solder just by itself it melts in like 1 or 2 seconds and it solidifies in about 3 ( I think about 3). The solder doesn't go shiny though it goes really misty, not shiny at all.

When I shake the iron it makes a weird sound like somethings loose in it.

Does anyone else have this problem? If I get a new soldering iron what should I get? between $10-$20. I would mainly use it for circuit boards an small pieces of wire, nothing massive.

 

[Peter M]

Hello protolisk,
when desoldering you need to first "wet" the iron with a small amount of solder (resin cored). This wet spot then needs to be placed against the solder you wish to remove (whilst the flux is still smoking).
The reason behind this is that air is not a very good conductor of heat. The resin flows across the gap between the iron and the solder removing the air gap, thus tranfering the heat better.

As well as this the iron has to heat up more than just the solder. It also has to heat up the coppper on the PCB the component leg and anything else in contact with the solder you are trying to remove.

When using a solder sucker, you basically need to sit it on the solder as it melts, and push the trigger as you remove the iron.

The solder will cool much quicker on the circuit board as all the copper and components act as a heat sink.

Several reasons for solder setting "misty"
1. movement as solder cools.
2. to much heat for to long.
3. not enough heat
4. trying to "paint" solder on.
5 to much/little solder (usually results in one or more of the above)


The process should be
1. wet iron tip
2. placed wetted iron against items to be soldered
3. add correct amount of solder/flux
4. remove solder
5. remove iron
all this should happen in around 1-4 seconds

The loose sound may be a temp control magnet??? Does it click as it heats up??

If you are going to buy another iron you will need to spend more than $10-$20, else you will just end up with another like you have. You really should buy something that is temp controlled and a minimum of around 50w eg. dick smiths t2200. But like most things you WILL get what you pay for... I still have a weller iron that I bought 20 something years ago, and there are much better irons than that around now.

Sorry for such a long winded answer, but one could write a book on soldering. No doubt someone has, but no-one would ever read it because soldering looks so simple.....??

 

[moxhamj]

I never bought a soldering iron - I used to win them by sending in circuit ideas to magazines. So I have got to use a few different types. The ones they sent me were about medium price range - temperature controlled rather than fixed watts. I must say the temperature control makes a big difference. My original fixed 40W one just didn't have the power, and did what yours is doing - just not heating the solder up enough. 60W ones with temperature control are running about 10W most of the time, but as soon as you put the iron on something that soaks up the heat, the iron comes on with the full 60W. So get one with a temperature knob on the front if you can afford it.

Re desoldering, you need to be heating and sucking solder at the same time, and you really need that thing all electronics enthusiasts wish for - a third hand! And maybe you need a fourth hand too - one for the iron, one for the sucker, one for the board and one to hold the pliers to pull the component out. Pulling old components can be a great way to get free stuff. Just be careful not to get molten solder on your eyeball like I did once.

It shouldn't take 20 secs to melt solder. Sometimes though, if the solder is a bit oxidised, the heat won't go through. I have found sometimes that adding a bit of new solder helps speed things up. Seems odd to add solder when you are trying to remove it but the component ends up hot for less time overall.

Lots of tricks for getting components out. Eg DIP ICs up to 16 pins or so - if you add solder to all the pins, and then run the iron quickly up and down the row of 7 or 8 pins and pull on the IC at the same time with an IC puller, you can usually get one side of the chip out. Then do the other side. But you will need at least 60W for that.

 

[hax]

Newer electronic items use lead free solder. Lead free solder has a higher melting point hence you need a hotter iron. But I would have thought 40w is more than plenty.

Also newer PCBs have much better heat sinking capacity, as they have more than two layers of copper, and are designed to be used without heat sinks. Hence as you have observed, the solder cools a lot quicker on the board.

So there's another couple of things working against you. What are you trying to un-solder? Surface mount components? If you want to re-use them, I'd say forget it. Better to use a hot air rework gun, but that costs $$$.

 

[Dippy]

I agree with all the above I think.
Yes, wet tip before soldering/desoldering.
Also, get a sponge cleaner. And also get one of those tip-cleaner little cake things that smell when you stick your tip in.

I have found that some tips require a lot of cleaning before they'll wet properly.

I use Weller and Antex station. They are 25W. They cost a lot, I only realised the value of more expensive stuff some years ago after using a cheapie and then using someone elses expensive one. None of this stuff is cheap stuff made in you-know-where.
I got a freebie 40Watter a couple of years ago made in you-know-where and gave it away. It was rubbish.

When soldering, your solder should melt and flow within 2 seconds.
Ditto desoldering and,yes, your sucker tip should be hovering over the molten pool. This action should also only take a second or two. Or else A) you'll overheat components, B) Overheat pcb and pad may fail i.e. fall off. (Important on prototyping (OH no, Stan/breadboards)).

Lead-free solder tends to look cloudier when solidifying and some cheap lead-free solder will actually look like a dry joint when, in fact, its fine.

If using lead-free solder a sligth word of caution. Some tips will be eaten away fairly quickly. As mentioned above it's a slightly higher melting point. So make sure you have a tip (usu iron plated) that is OK.

Sorry, but if you want quality, you'll have to pay for it.

If it rattles send it back. If the element is loose then it might not be making proper contact and maybe not getting full heat. Some older Wellers used a weird magnetic/sprung thermostat and rattled a bit.

You may be lucky and get a good little iron for £20. I would stick to the proper makes. They have been at it for years and have not just opened up a factory you-know-where to bang 'em out for 50p.

 

[manuka]

Protolisk: I too could pen paragraphs galore on this topic, but feel you should at least try SOLDER WICK. Pre fluxed wick desoldering (which exploits capillary action) is near magical in comparison to sledge hammer style hand suckers (which IMHO are virtually obsolete in todays micro electronic age). See => http://www.sparkfun.com/tutorial/SMD_HowTo/SolderWicking-1.jpg etc.

However commercial braided spooled solder wick can be elusive when needed, so make your own with VERY fine multi-strand wire, fluxed with lemon juice. Although I've access to all manner of professional soldering gear, I HIGHLY recommend this wicking technique for fiddly repair jobs & SMDs. Stan

 

[Protolisk]

The long answer is good.

When I heat the solder on the iron and it melts. Smoke comes out but only the first time. Not when i reheat a blob of solder. The iron then looks like its got a thin layer of water on it but that disappears really quickly. I got my solder in Malaysia with a really crappy soldering iron but I have no idea if it even has flux or whatever suppose to take away the oxidation. I could post a picture but I don't think it would really help. It looks like something from China but I have no idea cause its got Chinese writing on it but people in Malaysia speak Chinese.

I found out that loose sound was the tip was actually loose. It's fixed now I just tightened it.

However commercial braided spooled solder wick can be elusive when needed, so make your own with VERY fine multi-strand wire, fluxed with lemon juice. Although I've access to all manner of professional soldering gear, I HIGHLY recommend this wicking technique for fiddly repair jobs & SMDs. Stan

Wait. So you make your own wick? I didn't know you could do that. Is it easier than using a desoldering pump? Could you post a tut on how to do it?

I just bought the desoldering pump 2 days ago and it cost $12 and I only 14 so I don't earn that much. I don't really want to go buy a braided copper if I only just got the pump. Maybe I can return it?

I never bought a soldering iron - I used to win them by sending in circuit ideas to magazines.

Hmm in Australia?

 

[manuka]

See => http://www.youtube.com/watch?v=CuH3dWHipKI although this pans the activity out longer than normal! For DIY wick just use the finest strand cleanest copper wire around- coax braid may do. FLUX IS NEEDED ON DIY WICK- the commercial stuff is pre-fluxed.

NB- If you're only 14 then you really should first read & practice using a good overall tutorial on electronic soldering & de-soldering, as the field involves numerous skills & tricks of the trade. Typically months "on the job" are needed to be considered capable. It's near essential for your technique to be observed by someone experienced too, as just one poor solder joint can bring down a whole circuit.

Aside:In spite of my well known enthusiasm for breadboards I'm a soldering fanatic, as numerous past students of mine could no doubt verify! Stan

 

[Dippy]

"I'm a soldering fanatic" - you really ought to get out more Stan. You'll be photographing electricity pylons next.

 

[Peter M]

You'll be photographing electricity pylons next.

And what's wrong with that??? Riviting stuff that! Do you not photograph what you do? (yeah, yeah I should get out more too)

The smoke that comes off your solder is (or at least should be) the flux burning off your solder.
After this has stopped, that solder is basically waste, and as Dippy says you need to wipe your iron tip clean with some form of cleaning device. I use a damp sponge (nicked from the kitchen sink). Others use that curly bronze stuff.

And since a large amount of electronics comes out of Malaysia, I'd hazard a guess (yes I know some of you don't like guessess) that the solder is probably OK.

I should have added before step 1 in soldering wipe iron tip (in post #2)

 

[Dippy]

"Do you not photograph what you do?"
- no comment

 

[BrendanP]

lemon juice and braid

Stan, is the juice good to sue with off the shelf braid as well? btw jap. GOOT braid is the best I've used.

 

[papaof2]

How true!

It's near essential for your technique to be observed by someone experienced too, as just one poor solder joint can bring down a whole circuit. Stan

Even commercial wave soldering equipment doesn't always get every joint. My daughter's garage door opener started doing odd things (reversing just before closing completely, although there was no obstruction) so she attempted to adjust the limit switches. Then it stopped working completely.

We spent Easter weekend with them and I spent some time examining the mechanism - moving the limit switches in a couple of inches from end-of-travel, adjusting the up & down force controls, etc. Disconnecting the unit from power sometimes brought it back to life (LEDs lit in controls) but hitting a button to raise/lower the door shut everything down.

I went up the ladder with a very bright flashlight and checked all the solder joints on the board - unlikely problem in wave-soldered boards - but this is a high vibration environment. I found a couple of "don't like the looks of that" joints on the board-mounted power transformer, so took soldering iron (ancient Weller) and "real" solder (60/40 from 20 years ago) and redid the joints to my satisfaction.

Connected power to the unit and ran the door up and down, then adjusted the limit switches and force controls as needed. Ran the door up and down another 8 times - I think the problem is resolved ;-)

Since the transformer terminals are larger than the leads of any other components, the temperature of the solder in the wave soldering tank might not have been high enough to make a good connection on the larger terminals, or the terminals on the transformer may not have been properly cleaned before insertion in the board.

Exactly as Stan said, one bad solder joint can bring down a whole circuit.

John

 

[manuka]

Dippy: Make that " a fanatic for correct soldering techniques"
Brendan: All commercial solder wick is pre-fluxed - only quickie DIY stuff needs extra fluxing.
Papaof2: A great example- my swish mains shaver gave similar bizarre woes until a dry joint was re-soldered.

Thought for the day: A typical circuit has 1000s of soldered joints, akin perhaps to the numbers of nails/screws holding a house together. Yet a single missed/bent nail will rarely cause the building to collapse, unlike the soldered equivalent.

 

[Protolisk]

thanks for the help.

I'll make my own wick and keep the solder pump.

 

[Ralpht]

Hi Protolisk,
I used to teach what was called "Laborotory Standard High Reliability Hand Soldering" in the RAAF (Royal Australian Air Force)many years ago. That included re-working multilayer PC boards.

Other than using the right tool for the job, the bottom line is cleanliness. Everything must be clean before you solder - The copper pad the component goes into, the soldering iron tip , the component lead and the solder. The means mechanical cleaning and then chemical cleaning.

It was not unusual to take half an hour to put one resistor in correctly. Not practical in a commercial sense but when absolute reliability was needed, it was the only way to go.

No matter what, do NOT put lots of solder onto a joint. There must be a minimum of solder, just enough to cover the pad and having a small cone around the lead. The solder should have a Rosin core. This helps clean and "wet" the joint so that good heat transfer and solder flow can take place.

Otherwise you will make a poor job. Sure it will work initially but over time, the joints will fail, usually at a critical time.

You must get an iron that can handle the load on it. The moment you apply solder to a tip and then apply the tip to a component and track, the tip will cool down. Sounds like what is happening in you case and you are creating what's known as a cold joint.

The iron must be able to rapidly compensate for any load on it and it should not take any longer than 1/2 second to melt solder on a track with a lead in it.

On average the tip temp must be between 320 and 360 degrees for the chance to do a good soldering job with the standard lead based solder and at least 50 deg higher for non lead based solders.
Thats why as mentioned earlier by others, a temp controlled iron is critical.

Do not base the ability of the iron on watts only - means nothing. Tip temp and the ability to maintan that temp under load is what counts. Plus; as I said earlier, the tip must be clean to transfer heat to a pad/track otherwise you're going to do a poor job.

For de-soldering, solder wick is only good for single sided boards. The moment you want to desolder from a double sided board you will run into trouble and the hand bulb desolder tool just won't cut it unless you are very lucky.

I know you're only 14, therefore have a serious lack of money but if possible try to save up for and get you parents to help with getting a decent re-work station. It will be worth it's weight in gold if you take up electronics seriously and will last for most of a lifetime. I have a Royel rework station that does everything, about 20-25 years old and cost a fortune back then. Still going strong with only the vacuum pump needing minor servicing.

At the very least get a good temp controlled iron.

Good luck.

 

[Protolisk]

WOW 25 years old. Well I don't know about getting a desoldering station but probably a soldering station, wouldn't be much point in getting one if I haven't even got a soldering one. I think I saw one on the dicksmith website for about $60. If I sound sarcastic I don't mean to be.

 

[Logic Rules]

I have been soldering since the age of 7, and one thing has been paramount:
Keep a clean, wet tip, and the proper temperature. This does require some knowledge of how to maintain the particular iron you are using.
In most cases this is supplied by the manufacturer but in some cases you have use the basics of soldering to get to the point you wish.
There are many places on the ‘net that explain it. Do a search on ‘how to solder’.
Once you have the “knack” down you will enjoy many projects because of it.

 

[olden]

I, like you are new to all this so the people answering your question are giving a lot of good advice, after all they helped me which I found comforting.
The only thing I,m going to tell you about is de soldering I've used successfully. I can only use 1 hand so I purchased an electric de solder pump from 'Maplin' for £9.99. I know you are from a different country but look for a shop of electronics and they can help.
If any of the others come up with a different pump or ideas then I would bow to there experience and listen to them.
From the picture you can see that it is a soldering iron and the suction pump nozzle travels down the iron to the end. So heat and then operate the pump straight away. To me it is a god sent.

 

[Protolisk]

huh that one looks cool. I always thought they looked like this.

Yours looks really small and easier to use than the one above

I couldn't desolder the thing cause it had too many pins so I just started ripping to apart to separate the pieces.

EDIT::::::::
I just found this youtube video that uses a hot air thing and this suction thing.
hot air desoldering
probably cost a lot though.

 

[manuka]

Those hot air systems tend to the $$$$ level, but are a near essential for professional work. The heat shroud tips alone on a set I use are ~US$100 EACH! For skin flints I've seen paint stripping hot air guns used quite successfully, but they tend to blow hot air everywhere & cook nearby components & burn off insulation etc.

One handed electric de-soldering machines are indeed wonderful, but not without a lot of "fish hooks". Cheaper ones with long hoses tend to clog & require frequent maintenance- try to get a type with the motor in the handle & with a clear sight glass. However again allow $$($). Stan

 

[Dippy]

Ah, the problems of de-soldering double sided board components is nearly legendary.

Have you tried those plunger/spingy syringe things. Sometimes ridiculously called 'Desoldering Guns'. They range from the very cheap Beijing SolderSucker to very expensive (overpriced?) Edsyn.

As Stan says, pukka desoldering gear is v. expensive.

 

[Protolisk]

Do you mean the desoldering iron olden has.

or this one

I've got this one.

The other thing will probably be what I get after I get a soldering station.

 

[Dippy]

Yes, as per your picture. I thought you had the one as per your previous post with the red bulb thingy. As good as they are, they struggle with double sided pcbs.

Yes, soldering stations with adjustable temp control are ideal. Sometimes you will need to use different size tips and maybe smd tips, so temp control is ideal. Esp as you can get solders with different melt temps and diameters.
The quality of tip is also important from the wetting/corrosion aspects.
If you get a good, well known, brand you will be assured that you can get replacment bits in the years to come.
I use Weller and Antex which are the popular brands in UK. If things conk they can go back to manufs/dealers and be repaired for a small sum. Mind you, I guess, if they only cost a small sum intially then you an throw them away... I'm merely thinking of the environment.

Anyway, enough from me, I must solder on .... (soldier on? .. oh well never mind).

 

[olden]

Yes, as per your picture. I thought you had the one as per your previous post with the red bulb thingy. As good as they are, they struggle with double sided pcbs.

Yes, soldering stations with adjustable temp control are ideal. Sometimes you will need to use different size tips and maybe smd tips, so temp control is ideal. Esp as you can get solders with different melt temps and diameters.
The quality of tip is also important from the wetting/corrosion aspects.
If you get a good, well known, brand you will be assured that you can get replacment bits in the years to come.
I use Weller and Antex which are the popular brands in UK. If things conk they can go back to manufs/dealers and be repaired for a small sum. Mind you, I guess, if they only cost a small sum intially then you an throw them away... I'm merely thinking of the environment.

Anyway, enough from me, I must solder on .... (soldier on? .. oh well never mind).

http://www.picaxeforum.co.uk/images/smilies/wink.gif
You'll make rickharris groan saying "I must solder on...", I didhttp://www.picaxeforum.co.uk/images/icons/icon10.gif
Talking

 

[Logic Rules]

Hi,
You need to get a Vacuum De-soldering Tool. eBay has a bunch.
When the solder melts apply the vacuum and remove the soldering iron; this should be done immediately to avoid damage to the device. Care should always be taken so that the heat does not ruin the device. If all of the solder is not removed allow the device to cool before you try again.
In some cases it is almost impossible to remove all of the solder. It may be necessary to apply a small amount of pressure with needle nose pliers in order to free the connection.
You should practice removing a device like a diode. After it has been removed test it for functionality. If it works you have used the proper technique.
Good luck

 

[jpyle1]

Strange hot air system

I don't remember where I came up with this, a Tiawan special do-it-yourself hot air "gun??
30 watt, it provides uncontrolled heat and you blow in the custom (pipe stem) tube for application of hot air to your component. Poor boy special equipment. P.S. DO NOT SUCK!!!!
as it's design sucks enough for everyone. John

 

[demonicpicaxeguy]

burnt lungs anyone, if you do that use an aquarium pump