Need help soldering

[cpmer]

First off my soldering experience is very small. i installed a wiikey modchip in a wii over a year ago. It was only like 6 or 7 wires and the soldering points were all nice and big. Now im trying to install a ps2 modchip which is 21 wires and the soldering points are extremely small. I have an old broke ps2 that ive been practicing on and im running into some problems. Im using a fine tip 15 watt soldering iron with 60/40 solder and using 30awg wire. My main problem right now is im having trouble getting the solder to stick to the points. When i try to put solder onto the points the solder is going to the iron tip and not to the points. Ive tried 3 different methods.

First i tried the method ive seen most people use on youtube videos which is take a piece of solder, place it on the the solder point then place the iron onto the solder so that it melts it onto the soldering point. Problem is the solder is going to the iron not the soldering point. Second method is just put a lot of solder onto the soldering iron tip then place the iron tip on to the soldering point to cover it with solder. Problem with this method is the points are so small it can get messy and 90 percent of the time the solder just stays on the soldering tip. 3rd method ive tried and suggested by some of the people who have installed these chips is just tin the wire then place on the soldering point and solder it which ive tried but again 90 percent of the time it doesnt stick or the connection it makes is so weak that breaks off way easily.

I feel like im doing this all wrong because when i watch the youtube video and see the pics online all the soldering points are nice and round. Mine are a mess, the points usually have huge spikes that i cant figure out how to solve. Ive tried different speeds of pulling away the iron tip but still i get a big spikey tip. Heres an example of what i would like my install to look like and im hoping someone can help me out with nice and clean

 

[herm0016]

for small stuff you should get some liquid flux. it will clean the points and will help the solder stick. i like the liquid better than the past for small things. I have also found that tining the wire and the pad is the best method.

 

[cpmer]

i have flux but its the paste kinda. Im not sure how to use can someone explain how to use it

 

[bobsmith1492]

What do you mean by paste kind of flux? Usually you'd use something like a flux pen - it has a big spongy tip and you poke it onto the board to release flux.

Also placement of the iron and solder relative to your soldering point is critical especially on something small. Put the iron tip right on the edge of the pin and try to poke the solder in between the iron and the pin. If it still sticks on the iron, use that to your advantage - rotate the iron tip and put the solder bit right on the pin. If it still won't adhere, clean your iron tip (quick light strokes away from you with a DRY wad of paper towel is good), tin it again (dump a LOT of solder onto the tip, enough to make a big glob that is ready to fall off then flick it off - not on your board though!) and clean it again with the paper towel. Ideally, then you would put flux on the part you're soldering and try again.

 

[Modelworks]

As suggested you need a flux pen.
Make sure your using flux designed for electronics and not plumbing.
Get a good magnifying glass or jewelers loop, it helps tons.

 

[mindless1]

Originally posted by: cpmer
i have flux but its the paste kinda. Im not sure how to use can someone explain how to use it

As Modelworks mentioned the normal and best flux is typically a rosin based (in alcohol solution) liquid. Rosin paste can work, some nearly neutral PH water based can work but are harder for beginners, and acid based typical plumbers Zinc chloride will do the job fine BUT remains corrosive.

Whatever you use you will want to clean off the excess when finished and a little goes a long way. Test this, smear some, a tiny bit of flux on some old worthless electrical thing you have, a practice solder joint, heat it up to reflow the solder then let it cool and see if you can reasonably get the residue off. Alcohol is a typical solvent for rosin based, water for water based, and strong detergent solution for the (typically petroleum jelly based) plumber's. Once you have confidence you can clean it off, proceed to the actual joints you need to solder.

Put a dab of flux on the joint. Prepare your iron by cleaning the tip if necessary, dipping it in the flux and using a moderate abrasive substance (I mean barely so like a paper towel) to wipe off ALL the solder quickly in brief brushing actions. Do this reasonably quickly and re-tin the tip with some solder but just a tiny bit.

touch the tinned solder tip to the spot on the PCB with the flux over it. No addt'l solder is needed, the solder already on the tip should flow onto the solder pad. Repeat this for each addt'l pad, but if your iron is hot enough it's cooking the flux on the tip and making a lot of burnt residue, wipe the tip off with the paper towel again and re-tin it. Re-tin it just slightly when the solder on it is being depleted by plating each solder pad, you won't have a big blob of solder on the tip and may actually have too much solder on some or all pads already and may need to clean that off with some desoldering braid.

After all pads are tinned, is your wire insulated with enamel? If so clean off the end being soldered, sometimes that coating will come off by just putting a ball of solder on the tip and putting the end of the wire in it for a few seconds, other times a lit match or lighter will burn it off. Other times it's quite stubborn and will need sanded off (or use different wire instead). After whichever method of removing enough insulation, wipe off residue with the paper towel and dip just the last millimeter into the flux paste. Repeat the process you used to tin the board pads, have a little bit of solder on the iron tip and touch the fluxed end of the wire lead to it for a second. Don't leave a big glob of solder on the end of the wire you are just plating it.

After all wires are prepared this way, make sure iron tip is clean and lightly tinned again and set down the wire on the pad then put the iron tip on top of the wire. The picture you link shows about 3-4 times as much solder as you need. Using way too much solder is a common mistake, but maybe half as much solder as in the picture would be a more reasonable goal for the first time you're doing this.

If you don't have the desoldering brand then just pick up where you left off, put flux over the blob of solder and reheat it while inserting the already tinned wire end.

I have pretty steady hands and this job isn't very tiny but I also find it can help to rest your elbow on the desk and have the work surface elevated a little more than typical desk to head height, else you're bending over alot which is ok for such a short job but the more you bent over the more likely you also block ambient light if you don't have a good aimable lamp to the side.

 

[soccerballtux]

DON'T GET ROHS SOLDER WHATEVER YOU DO DON'T GET IT!!!!!!!!!!
I CANNOT STRESS THIS ENOUGH!!!!! SOLDERING WITH ROHS SUCKS!!!!!!!
imho

Heat the solder from the PCB pad up to ensure you don't get a cold solder joint.

 

[cpmer]

how long can i keep the iron on the joint for before it can ruin it? Also what does rohs stand for and why shouldnt i use it?

 

[mindless1]

I should add that there are a couple other things handy if you prefer and are able to do the soldering in one step instead of tinning both parts first. Since you only have two hands, one for solder and one for iron, either make the wire longer than it needs be and tack it down so it doesn't move, or use something like a "helping hands" device to hold the wire still while soldering.

 

[mindless1]

Originally posted by: cpmer
how long can i keep the iron on the joint for before it can ruin it? Also what does rohs stand for and why shouldnt i use it?

Maximum time varies based on effectiveness of iron heating element to get heat to tip, stoutness of tip, area of metal, thickness of metal, quality of bonding to PCB carrier.

In other words we can't give you a specific number but generally if it isn't soldered down in 2 seconds something is wrong and you should examine your tip to see if there is crude that needs cleaned off then lightly retin it because needing to spend more time on someting this small is usually a sign the tip isn't making a good thermal junction with the pad you're soldering to.

It takes less than a second to solder something so small if you have (enough) flux on the joint, otherwise the solder will just be melted globs and heating longer won't help as much as stopping and putting flux on before retrying.

ROHS is reduction of hazardous substances which in this context just means lead-free solder which often has a higher melting point, and for someone not used to using it, it is more difficult to tell if the resultant joint is high quality as it doesn't always end up with a really smooth shiney sheen to it after it has flowed well. Typical easy to use solder for this would be marked 60/40 or 63/37 SNPB (Tin/Lead).

 

[cpmer]

Ok i was practicing last night and all was going well i got the hang of the all points i needed to solder so i went ahead and tried doing it. Things imo were going great until i reached points q t u v and r heres the link to what im talking about diagram Little did i know it but i guess i bridged between Q and T and U and V. I tried to use desoldering braid to clean up the solder but it all it did was flatten it out. Ive never used desoldering braid before so i dont know what im doing if anyone has some good techniques to clean ALL the solder up please let me know. Also whats frustrating is this is a 21 wire install its so hard to troubleshoot why its not working either. Is there anyway to test for shorts or something with a volt meter. I have one but dont know how to use it or what to look for?

 

[Modelworks]

Apply more flux and use the braid.
If that is not working for you , you can try applying more solder , then using the braid again.
The braid needs to contact the solder and if it can only contact the pins then its not going to wick up the excess.

You can use the meter to check for shorts if it has an ohm setting.
Set it to ohms and place one lead on each pin that are next to each other.
If it reads 0 ohms then you have a short.
If the probes are too big to put next to each other on the pins, then attach a sewing needle to each probe and use that.

 

[bryanl]

Touch the iron's tip to the solder joint, and immediately push solder into the junction of the joint and the tip. Applying solder to the parts beforehand has the disadvantage of preventing the flux from doing its work.

15W is more than enough power for melting solder to 30 AWG wire, but it may be inadequate for heating a circuit board or solder lug sufficiently. 25-40W is usually better for general purpose use, but 4+ layer circuit boards can require as much as 60W! (temperature-regulated is also desirable, to prevent overheating). Believe it or not, too little power is more likely to cause heat damage than too much power, by requiring far more time to melt the solder.

Apply solder to the wire before attempting to solder the wire to something else.

Keep the iron's tip perfectly clean and coated with solder because a dirty tip can reduce heat conduction to much less than half.

 

[Howard]

It won't help the problem you have now, but get 63/37 solder.

 

[davesaudio]

Some braids are better than others
on a crappy braid wiping you flux pen across it before use will help.
Bryanl nicely covered the issue w the 15w iron

 

[amheck]

no offense, but this is highly technical? Am I the only one scratching my head here?

 

[nineball9]

Originally posted by: amheck
no offense, but this is highly technical? Am I the only one scratching my head here?

Perhaps not, but I give the original poster a lot of credit for trying and learning how to solder. It requires more work and learning than "building a PC" with just a screwdriver and a credit card!