The Living Soldering Thread

[mkawa]

nylon brush (toothbrush works) with a solvent. IPA is ok, but sometimes (especially with old flux) you need to get draconian. chemtronics and mg chem both sell flux removers that are like every single organic solvent all at once. i've had the most success with those when i have a _lot_ of flux on a board.

also remember that once you break down the flux residue with ipa or some other solvent, warm water washes are actually really effective. just make sure you dry the board out with alcohol or time after

[Photekq]

It's brand new chip-quik tacky flux & kester 44 flux. I'll give toothbrush + IPA a try and if that doesn't work I'll look into some flux remover. Thanks guys!

[komar007]

Those LCD monitor wipes in cylindrical plastic boxes work well too. Just literally pour the board with IPA, and then wipe. Unfortunately, you'll need to remove the torn parts of the wipes afterwards.
EDIT: I meant something like this: http://www.aliexpress.com/item/88pcs-PC-TV-LCD-Cleaning-Wet-Wipes-Professional-Nurse-0374/391523790.html

[MOZ]

I like to use petrol with a tooth brush, I've heard that is what is used in small-scale industry, at least here in India.

[mkawa]

that's probably the only thing worse for you than using pure isopropryl like i do. congrats ;P

i used to wear gloves because your body absorbs pure alcohol so readily through the skin, but a while ago i just gave in and now i'm a step away from using kerosene like moz

[mkawa]

Those LCD monitor wipes in cylindrical plastic boxes work well too. Just literally pour the board with IPA, and then wipe. Unfortunately, you'll need to remove the torn parts of the wipes afterwards.
EDIT: I meant something like this: http://www.aliexpress.com/item/88pcs-PC-TV-LCD-Cleaning-Wet-Wipes-Professional-Nurse-0374/391523790.html

these wipes are just iso on a fibrous carrier

[MOZ]

that's probably the only thing worse for you than using pure isopropryl like i do. congrats ;P

i used to wear gloves because your body absorbs pure alcohol so readily through the skin, but a while ago i just gave in and now i'm a step away from using kerosene like moz

Hey, it works! Should I be worried about handling gasoline directly, bare hands?

[mkawa]

yes, yes and yes, to say the least. highly carcinogenic

[jdcarpe]

This is the feeling I get about India. They just use whatever works, regardless of the consequences, they're like, "Might cause cancer? Ah, screw it." One day they may have an OSHA equivalent to safeguard the workers, but until then...

[tjcaustin]

This is the feeling I get about India. They just use whatever works, regardless of the consequences, they're like, "Might cause cancer? Ah, screw it." One day they may have an OSHA equivalent to safeguard the workers, but until then...

Same country that still doesn't have a modern sewage system, right?

[MOZ]

This is the feeling I get about India. They just use whatever works, regardless of the consequences, they're like, "Might cause cancer? Ah, screw it." One day they may have an OSHA equivalent to safeguard the workers, but until then...

This is the problem with my country, and we call it "jugaad", a fix that works, what we don't realize are the short-falls.

This is the feeling I get about India. They just use whatever works, regardless of the consequences, they're like, "Might cause cancer? Ah, screw it." One day they may have an OSHA equivalent to safeguard the workers, but until then...

Same country that still doesn't have a modern sewage system, right?

Yes, the same.

[Pacifist]

How important is flux?

Oh and I finally soldered for the first time. Just the pins on a pro micro, but it was really satisfying

[tjcaustin]

How important is flux?

Oh and I finally soldered for the first time. Just the pins on a pro micro, but it was really satisfying

flux is super important, it helps solder flow right.

[Melvang]

How important is flux?

Oh and I finally soldered for the first time. Just the pins on a pro micro, but it was really satisfying

flux is super important, it helps solder flow right.

With current offerings of flux core solder the I can't really thing of many reasons that one would need to purchase standalone flux for what the majority of us do. 

[tjcaustin]

How important is flux?

Oh and I finally soldered for the first time. Just the pins on a pro micro, but it was really satisfying

flux is super important, it helps solder flow right.

With current offerings of flux core solder the I can't really thing of many reasons that one would need to purchase standalone flux for what the majority of us do.

I was assuming he was going lead free or something.  For some reason.  Flux itself is important is what I was getting at.

[Photekq]

With current offerings of flux core solder the I can't really thing of many reasons that one would need to purchase standalone flux for what the majority of us do.

Having some standalone tacky flux is VERY helpful for SMD soldering..

[Melvang]

With current offerings of flux core solder the I can't really thing of many reasons that one would need to purchase standalone flux for what the majority of us do.

Having some standalone tacky flux is VERY helpful for SMD soldering..

Very true, I forgot about that whole can of worms as I mostly do through hole stuff.  I guess it can also be useful for when attempting to get the last tiny troublesome bits of solder from through holes on a dual sided PCB as well.

 Question for myself.  How much of a difference is there between 63/37 and 60/40.  The reason I ask is because I watched a video about that talked about the "wetting temp" of solder and that 63/37 basically would stick as soon as it was hot enough to melt.  Well this got me wondering and I looked at what I have.  It turns out the stuff I bought from radio shack was 60/40.  I haven't had any issues with it as I am probably running my iron a bit on the host side anyway.

[jacobolus]

Question for myself.  How much of a difference is there between 63/37 and 60/40.  The reason I ask is because I watched a video about that talked about the "wetting temp" of solder and that 63/37 basically would stick as soon as it was hot enough to melt.  Well this got me wondering and I looked at what I have.  It turns out the stuff I bought from radio shack was 60/40.  I haven't had any issues with it as I am probably running my iron a bit on the host side anyway.

In general, 60/40 should work fine. The advantage of 63/37 is that there’s a single temperature at which it goes from all-solid to all-liquid, so it will either melt or solidify very quickly right when it crosses that temperature. 60/40 solder has a small range of temperatures that are in between the freezing/melting points, where the solder is a sort of paste of mixed solid/liquid (“plastic”). From what I understand, if the solder gets moved around while it’s in this state, it can result in a worse solder joint [it will end up looking dull instead of shiny, and can be unreliable].

[HoffmanMyster]

With current offerings of flux core solder the I can't really thing of many reasons that one would need to purchase standalone flux for what the majority of us do.

Having some standalone tacky flux is VERY helpful for SMD soldering..

It also saved me when I was soldering things with gigantic leads, as it would have otherwise taken minutes to heat up the leads, but the flux helped a ton with flowing the solder.

[mkawa]

With current offerings of flux core solder the I can't really thing of many reasons that one would need to purchase standalone flux for what the majority of us do.

Having some standalone tacky flux is VERY helpful for SMD soldering..

for SMD, make your old solder paste: get a hard lacquered ceramic or stainless steel mortar and pestle and smash some solder and a bit of extra flux. suck that up with a fine tipped syringe and apply on your solder pads. then use a suction holder and blow hot air as the suction holder is holding the part on the pads. bam! ezpz smd.

if you don't have hot air, same deal but apply the contact iron very very briefly on each joint as you hold the part in place.

[mkawa]

From what I understand, if the solder gets moved around while it’s in this state, it can result in a worse solder joint [it will end up looking dull instead of shiny, and can be unreliable].

(by the way, it's glass transition, not plastic. the material is plastic during glass transition. anyway..)

a "cold" solder joint is one that has an interrupted bulk material electrically joining the two parts. in other words, there are fractures in the solid solder that is carrying current between the two materials. it's possible to create these fractures by accident regardless of whether your soldering alloy is eutectic or not, but you're much more likely to create these fractures and voids by accident with a soldering alloy that is not euctetic. it's pretty easy to see why when you think about it at a molecular lev..

bottom line: keep your joint very still when it is cooling and use euctetic solder if at all possible and you will have the highest percentage of good points. further, to "fix" cold joints with euctetic solder. you generally just melt it again (add a tiny bit of flux to get it to crystallize and to move further onto the two joined pieces) and then let it cool without putting pressure etc. on it.

[mkawa]

just dropping this off here: http://tangentsoft.net/elec/movies/

tangent, as he was known on headwize and otherwise nom de guerre, was an early mentor of mine in hobbyist electronics. didn't know he made a video series. looks good!

[SpAmRaY]

^^ tangent made me my first headphone amp

[mkawa]

it's too bad his shop finally closed. is there any way short of custom board orders to get a pimeta v2 board these days?

[SpAmRaY]

No idea last I did business with him was ~10yrs ago.

[Ishamael]

Would the CL1481 iron being offered in the learn to solder group but be up to the task of desoldering a QFR for practice?

[tjcaustin]

Would the CL1481 iron being offered in the learn to solder group but be up to the task of desoldering a QFR for practice?

Very much so

[Ishamael]

Awesome, thanks!

[kmiller8]

Would the CL1481 iron being offered in the learn to solder group but be up to the task of desoldering a QFR for practice?

Very much so

To add to this, be careful with the QFR PCB, it's ****, If you're not quick and careful with the desoldering, you will lift pads.

[swill]

Would the CL1481 iron being offered in the learn to solder group but be up to the task of desoldering a QFR for practice?

Very much so

To add to this, be careful with the QFR PCB, it's ****, If you're not quick and careful with the desoldering, you will lift pads.

+1 to this.  I had to resolder 5 switches and I lifted 4 pads and one pad was missing a side, so the solder would not even fill correctly...  It is back to working, but what a gong show...

[SpAmRaY]

Just wanted to say thanks for this thread. I am no longer a soldering virgin!

[Ishamael]

Thanks for the feedback guys.

[mkawa]

when desoldering with a soldapullt, hold your pullt off to the side, put a tiny bead of melted solder on your tinned tip, and touch that to the joint (that tiny bead is often called a heat bridge). you should see immediately when the solder in the joint melts, as it will suddenly become very shiny and may change shape slightly to become more of a perfect sphere than it was before. as soon as that happens, hit the button on your soldapullt. the suction of the GH soldapullt is so high that it doesn't have to be right on top of the joint in order to grab most if not all of the solder. holding it at a 45 degree angle with maybe 1mm separation between the tip and the solder should be enough to grab the vast majority of the solder.

[tgujay]

when desoldering with a soldapullt, hold your pullt off to the side, put a tiny bead of melted solder on your tinned tip, and touch that to the joint (that tiny bead is often called a heat bridge). you should see immediately when the solder in the joint melts, as it will suddenly become very shiny and may change shape slightly to become more of a perfect sphere than it was before. as soon as that happens, hit the button on your soldapullt. the suction of the GH soldapullt is so high that it doesn't have to be right on top of the joint in order to grab most if not all of the solder. holding it at a 45 degree angle with maybe 1mm separation between the tip and the solder should be enough to grab the vast majority of the solder.

So you're saying your soldapullt really sucks

[mkawa]

bwa!

exactly

[Wildcard]

mkawa what's a good place to pick up a pair of Edsyn KP101 flush cutters? My Hakko CHP-170's are ready to be retired and I recall you talking about these. I ordered a pair on amazon from "Majesty Supply" but they sent me some crap $1 cutters which I promptly returned. Are there any good reputable sources you can suggest to order these from?

Also any recommendations on good ESD tweezers?

Edit: I guess I could order these directly from Edsyn, unless there's another option.

[mkawa]

edsyn's minimum order is way above the cost of a pair of kp101s. i have plenty of stock right now. i _don't_ have stock of tweezers, but edsyn's higher end tweezer line is quite nice. wiha tweezers are my go-to for fine manipulation, but i have a pair of edsyns like i like as well. i might be able to get you a small  discount on the edsyns if you can identify what size and tip-type you want.

i'm fine with sending out kp101s alone, but if you're international and you've already been through a pair of CHPs (which is perfectly normal -- they are junk), i would suggest buying a full on larsen flush cutter -- either one of their carbide series if you're doing big wire work or the smaller standard series for nipping at component legs.

ps, oddly, i am also a wiha stalwart but i absolutely don't recommend wiha cutters anymore. the only pair i have that have held up was the wiha germany bevel head and it's more expensive than the equivalent larsen and has a much less beefy joint. it's full polish, and the box joint is definitely high quality, but the larsens just blow it out of the water.

[jacobolus]

[...] i would suggest buying a full on larsen flush cutter -- either one of their carbide series if you're doing big wire work or the smaller standard series for nipping at component legs.

ps, oddly, i am also a wiha stalwart but i absolutely don't recommend wiha cutters anymore. the only pair i have that have held up was the wiha germany bevel head and it's more expensive than the equivalent larsen and has a much less beefy joint. it's full polish, and the box joint is definitely high quality, but the larsens just blow it out of the water.

I bought some pliers and cutters from http://schmitz-zangen.de/shop.php?lang=engl which were quite reasonable in price, and seem to be very well made (though the shipping from Germany to USA takes them a while).

[Wildcard]

[...] i would suggest buying a full on larsen flush cutter -- either one of their carbide series if you're doing big wire work or the smaller standard series for nipping at component legs.

ps, oddly, i am also a wiha stalwart but i absolutely don't recommend wiha cutters anymore. the only pair i have that have held up was the wiha germany bevel head and it's more expensive than the equivalent larsen and has a much less beefy joint. it's full polish, and the box joint is definitely high quality, but the larsens just blow it out of the water.

I bought some pliers and cutters from http://schmitz-zangen.de/shop.php?lang=engl which were quite reasonable in price, and seem to be very well made (though the shipping from Germany to USA takes them a while).

Not bad, did you pick up the 3437HS22? It looked good until I switched countries to the US and saw that shipping charge. Ouch

[mkawa]

quite intrigued by the stainless line. bought a couple to see how they compare to my very similar looking wihas.

[jacobolus]

Not bad, did you pick up the 3437HS22? It looked good until I switched countries to the US and saw that shipping charge. Ouch

I didn’t get any tungsten carbide cutters. The shipping is steep to the US, but it doesn’t increase much for additional items, so if you buy about 3-4 cutters/pliers at once, the price ends up okay. Would obviously be even better with a group buy or something.

[mkawa]

their carbide cutters is only a carbide plating. they are not full carbide. the problem with this is that you can't sharpen cutters like this or you take off the carbide layer.

tronex has full and brazed carbide cutters, but they are meant for extremely thin medical grade and otherwise strong but thin wire. the tronex T and W series top out at 24AWG (but of course they can cut stianless and other very hard wires).

that said, i have heard extremely good things about tronex's carbon steel full flush and extra full flush cutters (like, best cutters ever sort of good things). very much debating picking up a large gauge cutter, as those take the biggest beating. that said, for very hard wire your best bet is an end cutter like the wiha 32659. the 150$ tronex full tungsten carbide cutters are for like.. laparoscopic surgery (ok they're probably a bit low-end for laparoscopic procedures), and not nipping off component legs.

[Melvang]

I can't stress buying quality cutters enough.  I tried cutting some spring steel piano wire with some cheap masterforce cutters from Menards.  Yeah they won't hardly cut the paper that ties diodes together anymore.

[mkawa]

the trick is replaceable blades

[jacobolus]

I tried cutting some spring steel piano wire with some cheap masterforce cutters from Menards.

That Schmitz website tells you what maximum gauge/mm width of various hardnesses of wire to safely cut with each type of cutter. For piano wire, yeah, I’d use the tungsten carbide ones. I think many keyboard springs aren’t using wire that’s quite so hard though. Keyswitch spring wires are thin enough that even the smallest of the tungsten carbide cutters should work for any of them though, even if they were piano wire.

[Melvang]

I tried cutting some spring steel piano wire with some cheap masterforce cutters from Menards.

That Schmitz website tells you what maximum gauge/mm width of various hardnesses of wire to safely cut with each type of cutter. For piano wire, yeah, I’d use the tungsten carbide ones. I think many keyboard springs aren’t using wire that’s quite so hard though. Keyswitch spring wires are thin enough that even the smallest of the tungsten carbide cutters should work for any of them though.

Yeah I knew it would destroy them but I didn't care.  I was using that wire to sleeve some 9 foot long pieces of 20 gauge wire with 1/16" cable sleeving.

[BlueBär]

I have some tiny pins that I want to connect to some 1mm thick copper wire. The pins already make it hard enough, but the solder doesn't want to "stick" to the copper wire at all. Am I doing something wrong?

[mkawa]

flux!

[BlueBär]

Tried again, flux did not really help. I used some wire from some old earplugs and wrapped that around the pins which worked.

[mkawa]

so, if it's stranded wire, and you're short on hands, apply a little bit of blobby solder to the twisted stranded end. then, apply flux and the flux will wet the wire such that capillary action draws the solder into the wire bundle. after this happens, your wire will be "tinned", and should look silvery (because it has a coat of tin and lead on it). now, solder "sticks" to solder when heated, so put a little bit more blobby solder on the tinned wire, put a little blob of solder on your tip to serve as a heat bridge put a drop of flux on either the pin or the wire's block, touch the wire blob to the pin and then maneuver your iron to where your heat bridge is touching the blob on the wire and the pin. pull the heat back as soon as the solder melts and then hold the assembly extremely still (this is where a proper wire holding (pana)vise really helps) and you should get a good joint. if you don't (which is A-OK), put the assembly in a work holding device, put another drop of flux on the bad joint and heat for just long enough for the solder to melt, then pull the heat back.