how do you solder?

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I have tried everything. it simply doesn't work.

i read that you should let the joint melt the solder. that takes about 1 minute per connection and often leaves marks on the board.

i guess i just can't solder anything. I've wasted about $10 in stuff with my first project, and gave up. now with this next, simpler project, i've already ruined $1s worth (messed up early). should i just use some glue and tape and hope for the best?

so how are you supposed to solder. and how do you remove solder when you mess up every 2 seconds. I have a nonfunctional desolering bulb with a now melted tip. I have no idea how you're supposed to get suction while melting the solder with it.
 
Retired diyAudio Moderator
Joined 2002
Chris, in addition to following the basics in soldering, I would recommend buying a good soldering iron. I used to have a cheap radioshack, and had all kinds of problems, iron taking a long time to heat up, overheating solder joints and cold soldering joints. I picked up a good weller iron, and haven't had any problems since. I bought the WTCPT on clearance, but you should be able to find cheaper ones that are also good. Here is a thread on soldering irons:
http://www.diyaudio.com/forums/showthread.php?s=&threadid=8058

Happy New Year!

--
Brian
 
Soldering 101.

1: Use the right solder. 37% tin, 63% lead solder has the lowest melting temperature and also transitions the cleanest from liquid to solid state (no plastic in-between state reduces chances of getting a cold solder joint). For general purpose soldering I like Kester multi-core the best. There are religous wars fought here about is the best solder, but this is good enough for me.

2: Use a proper iron. I like temperature controlled soldering stations (Hakko, Metcal, Pace, Weller) since you can set the temperature correctly for the kind of solder you are using and they maintain that heat automatically, even on thick traces. The Metcal is my favorite when someone else is paying and the Hakko 936 is my choice when the money is coming out of my own pocket. Try and borrow a good iron to see for yourself, you will not believe the difference it makes.

3: Clean the copper surface you are soldering to. Copper pads/traces on DIY PCB's tarnish pretty fast. Use a 3M green scrub pad to clean up the pads before you start. I also like to use a Flux pen on DIY PCB's to make sure I have a really clean surface to solder to. This adds some mess to clean up, but really cuts down on how long each joint takes to solder.

4: Make sure you have a clean, well shaped tip on your iron. If you iron's tip won't wet properly with solder then replace it. Alway wipe the tip clean on a damp sponge and apply a tiny ball of solder to the tip before soldering each joint. Make sure you press that little ball of solder into the joint (speeds heat transfer to the copper).

5: Apply the iron to both the component lead and the pad at the same time. Wait a second or so and then feed in about an inch (25 mm) of solder into the joint. Remove the solder then the soldering iron (be careful to not move the component leads while the joint is cooling).

6: Examine the solder joint critically. If the joint looks grainy or jagged then it is probably not a good joint, remove the solder and try again.

***************************************************

Removing solder from PCB's. It is important not to put too much heat into the joint or you will lift traces from the board. There are four options I use to remove components:

1: Cheap IC? Clip the leads off the body of the IC first, then deal with each lead using one of the other following methods. Trying to get IC's out of PCB's is usually more trouble than it is worth. Put big IC's into sockets (you can always solder them into the board after final checkout if desired)

2: Traditional heat and suck. Solder suckers vary a lot in quality (and a worn out tip makes them all worthless). Not my favorite method, but usually works most of the time. Downside is you can easily overheat the trace and or the component. You will often have better luck if you put the soldering iron on one side of the PCB and suck from the other side.

Note: If you are not able to clear the hole with the first attempt, add some solder for repeated attempts, any daylight showing around the pin will prevent the needed suction.

3: Solder Braid. Good for cleaning up a PCB once the components are removed, especially for surface mount pads. Never had much luck using solder braid for removing components. To use put the braid down on the PCB pad and apply the iron to the braid and press firmly. Remove the braid and soldering iron together using a wiping motion. This will normally leave you with a brand new looking pad.

4: Heat and flip. I invented this method myself. Just heat the joint until the solder is liquid and then slam the PCB down onto the work surface. The solder will obey Newton's laws of motion and shoot out of the hole very nicely. Very fast and works surprisingly well most of the time. When done be sure to clean up all the solder spatter from the work surface (and your PCB). Errant solder will just pop off the PCB with some slight encouragement from a dentists pick or tweezers. Watch out you don't get too enthusiastic with the slaming action or you can damage other components on the board. I like to put a shop rag under the board to cushion it some and make cleanup easier.

5: Removing expensive IC's with lots of pins is not for the faint of heart. I find the heat and flip method will free most of the pins quickly without overheating the PCB or the IC. Carefully use a solder sucker on the few pins that don't clear from the flip method.

Note: A dental pick or fine point tweezers is manditory equipement for unsoldering components. No matter how clean you get the hole, there will always be a weak solder bond between the component lead and the hole or pad. If you don't break that solder bond by wiggling the lead until it is free before extracting the component, you will end up ripping traces off the board.

Phil
 
Ex-Moderator
Joined 2002
Phil

Very good tips, I agree with all of them:)
4: Heat and flip. I invented this method myself. Just heat the joint until the solder is liquid and then slam the PCB down onto the work surface.
Apart from the fact I invented this;) ;) ;)

You can also use Heat and Swing; similar to the above method, but you do not hit anything with the board, just finish the swing with a flick of the wrist, and you get the same result:) (not to be used in an area with expensive carpets though, good only for workshops!)
 
theChris said:
I read that you should let the joint melt the solder. that takes about 1 minute per connection and often leaves marks on the board.
Do this:

Put the iron to to both the pad and the component lead.

Dab a little bit of solder right between the iron tip and the thing you are soldering. This solder will melt straight away and greatly improve the heat conductivity between the tip and the joint.

Then immediately drag the solder (don't lift it off) to the other side of the thing to be soldered and wait just a tiny moment till it is hot enough to melt the solder.

As the solder melts, move it around a bit so the flux gets distributed here and there.

Been soldering 32 years now. At first I used to dab the iron on the solder and then try and wipe it on the joint like I was using a paint brush! Not recommended. :rolleyes:
 
Re: Re: Re: how do you solder?

AudioFreak said:


You're not the only one who started off like that... :bigeyes:

Everyone at school soldered like that, except me... There was this one guy who called himself the "solder master" he burnt his fingers, I laughed... I dunno... I taught a 12year old friend to solder alright it about 15 minutes.. i think you need someone to SHOW you how to solder.. anyone wanna make a vidio clip?? it could have kewl music and sound effects as well.. :) I would, but I'd have to use a REALLY, REALLY old (1980s, I think) video camera plugged into my TV tuner card.. :p NO THANX!!! you can do it..
 
ONEUPMANSHIP!

Hi, and a very Happy New Year to everyone.

It seems that I can 'out do' you all!


My first soldering experiences go back some 55 years to when I was about 5yrs old, when a great Aunt of mine (who had more facial hair than I have ever been able to grow!) tried to teach me.

I don't believe electric irons had been invented then, and we had to use an iron which was like a large lump of copper with a pointed end which was attached to something like a big screwdriver. It needed to be heated up with a paraffin blowlamp, or on the gas stove!

Later, having worked as a manufacturing jeweller and silversmith for some six years, I did pick up a few tips about good soldering practice, although a lot of what is soldered in this trade is 'hard soldered' which does require higher temperatures, different fluxes, and different techniques etc.

On a more serious note, which I hope will help the beginners who do experience problems, the vital point (which has been mentioned earlier in this thread) with electronics soldering (and to avoid the *minute* or so theCriss mentioned), is to have the heat transferred to the 'job' by a small quantity of *fresh* solder on the tip of the iron.

You can sit with a *clean* tip against an article for hours without it transferring sufficient heat (unless the iron is far too big or hot than it need be) and all you will do is slowly oxidise the leads and/ or copper traces, or burn something. This oxidation merely prevents any proper flow of solder as the components will not then 'wet', as they should.

Make certain the iron tip is clean by wiping it on a piece of damp sponge, and immediately after wiping it, 'tin' the tip with a suitable quantity of *fresh* (i.e. off the solder reel, as this will add some vitally needed flux as well) solder, and place the 'blob' of solder so that it touches equally against both trace and lead, exactly as haldor has said.

I say "suitable quantity" because this will vary between jobs and you will need rather more to say 'bridge' between loose- fitting or awkwardly placed items and those with dissimilar masses (like a heavy trace with a skinny lead), than if they are close-fitting.

Unfortunately, only experience will show you how much solder you need each time on the tip to do this optimally, but always start off with the *least* amount you can get away with.

Dont forget that all you are doing in this stage is transferring enough heat to *both* parts, similarly, and you should not be doing any actual 'joining' or soldering of the joint.

Assuming that the iron size and temperature are somewhere in the right region, after merely a *second* or so, you can try feeding in some solder to the joint which should melt right away into the junction between the two components.

I find it is generally better to use thinner gauge solder than the heavy stuff, because it melts more easily than the higher mass solder, and all you need is to use a slightly greater amount.

Ideally, the end of the solder wire should be fed into where all three parts ( i.e. both parts and the iron tip) come together, and keep feeding in enough solder to fill the joint so that it is electrically and structurally sound. Incidentally, always use the *least amount* of solder possible in order to achieve this.

A picture (which I don't have) of some well-made joins would save a thousand words here, but the result should be smooth to look at, with a clean and shiny surface, with a meniscus where the outer edges of the solder is.
The join should look almost slightly hollow, rather than overfilled which would look bulbous instead.

Also, whilst I do it always because the 'sonic' results are better this way too, it will be easier to solder if you clean the leads (scraping carefully with a sharp blade works well) and the adjacent surrounding trace (a glass fibre cleaning 'pencil' is as good and cheap as anything for this) and then wipe both off with some electronic cleaning solvent like IPA (industrial alcohol).

*Do not*, under any circumstances then touch the areas which will be soldered, as the residual grease from your fingers (no matter how clean your hands are!) will tend to prevent the solder from 'flowing' readily.

I cannot over-emphasise this piece of caution, and I have watched professional plumbers swearing and cussing for hours when attempting to make sound joins, and after religiously cleaning the parts with wire wool, when they have then wiped the 'cleaning dust' or residue off with their fingers!

If the join doesn't form readily and quite quickly, you need to disassemble it, unfortunately, and clean everything up before trying again.

It is very little use to keep on adding more solder or flux, or whatever, if the join is already gobbed up with excess solder and/or is partly oxidised due to prolongued or excessive heat.

It can be frustrating at first, but if you follow the above and the other posters' guidelines, you will soon end up with perfect joins and will afterwards wonder what all the fuss was about.

Interestingly, I now have seven different soldering irons, myself, and a recently acquired fancy desoldering station to cope with all of the various surface mount devices, which cost me several hundred UK Pounds.

Furthermore, I have a spring actuated and a bulb actuated desolder tool, together with a self-powered electric desoldering tool which has a hollow tip and an inbuilt sucker.

However, for more than 95% of the time I spend soldering (and it is quite a lot!) I merely use the first electric iron I ever purchased some 40 years ago (an Antex 15 Watt which has had many new elements and a few tips etc., and which cost me about 3 UK pounds, then) and simple desoldering braid!

It just shows that although as some have quite rightly said in this thread that better equipment will make the jobs easier, they are by no means necessary, and you shouldn't be deterred if you can only afford fairly basic gear to begin with.

It never stopped me in the past when my gear was limited, even if it did slow me down a bit!

Regards,
 
pinkmouse said:
Apart from the fact I invented this;) ;) ;)

Glad to see I'm not alone here. My coworkers look at me like I am kind of strange when I do this.

I use a variation on the heat and swing to clean the soldering iron tip when I have to solder something outdoors. Just load up the tip with solder and give it a flick. The dross and excess solder is gone and you have a clean, tinned tip ready to use.

I have a funny story about other uses for the solder flick. I was a service tech 15 years ago and one of the other techs was promoted to service manager. He had a hard time moving into the management role. Any time one of us was in the shop he would come out and hover over you as you worked (guess he didn't really know what else to do). One day I was wiring up some harnesses and his hovering got annoying. After a few minutes I started "accidentally" flicking solder behind me onto his pants legs. A few minutes later he looked down and noticed his dress pants had taken on a real sparkle. I was very apologetic about that, but noticed he didn't hover nearly as close after that. :D

Phil
 
I never wipe my soldering iron tip clean... why?? cos I'm too lazy.. :p Probably would end up with better solder joints if I did, no that mine are bad.. :p lol I burnt my shoulder with a rather LARGE blob of solder... it was taking too long to cool, so I shock the PCB.. :( :rolleyes: I wasn't wearing a shirt at the time... IT HURT!!! I also burnt my finger tip, not with solder, but hot melt glue.. I was talking on the phone at the time.. :) I put some glue on my floor (yeah, my wooded floor) waited about 5 seconds (for the glue to cool down) and stuck my finger in it... The phone converstaion was pretting boring, had to find something to do.. :) :cool:
 
you guys are awesome. i had to work all day today, so i haven't started the re - retry out. i retried last night. I actually got it on without major problems. i was just using some radioshack pre-punched board. turns out it's not 16x16 as i thought, but 15x16. I put the first things on then noticed the relay wouldn't fit.

so i got a radioshack project box with larger board.

this is now in my favorites.
 
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