Solder Wick/Braid...What am I doing wrong?

[Siwastaja]

I have yet to see solder wick braid that doesn't work. Anything I have ordered so far, including Aliexpress, has worked like a charm for me. Maybe I've just been lucky.

You've been lucky.  I had some cheap no-name braid (via amazon) that essentially wouldn't wet. Brand name wick works.

I have seen bad solder wick, too. And semi-bad. Those kinda-sorta work, and if you add fresh flux, they work a tad better. And in a pinch you can indeed use any multi-stranded wire with added flux. But once you have used good solder wick, you don't want to use the crap, or something which needs added flux.

[CatalinaWOW]

In addition to the remarks above, make sure the solder wick is fresh.  It has a limited shelf life (not weeks, probably not months, but somewhere in the small number of years).  Adding flux sometimes will restore it, but sometimes not. 

Good contact between the wick and the solder is important.  Pressure helps on this, but as has been noted this can result in pad damage.  Practice on something you don't care about to figure out the right balance between wick effectiveness and damage to the pads.

[Veteran68]

Yeah, it cannot be stressed enough: NEVER apply pressure to the wick and scrub it around like you're trying to clean a frying pan. Press straight down, not too hard, and don't slide the wick across the pad while under pressure. The heat and roughness of the wick combined with the lateral forces will easily strip pads and traces off the PCB.

I cringe at a lot of YT repair channels where they do this. And then they express surprise/despair when a pad comes off.

[Smokey]

I have plenty of rolls of wick that don't work very well under certain conditions.

But I've never met a wick that didn't work with a bigger (hotter) metcal tip and a little paste flux.

Kester sp-44 flux activates anything.  But you better clean the board after.

[Dan123456]

One tip for OP, don’t forget solder braid is a consumable.

Once one part of it has been used, cut off the tinned part and use fresh stuff 

I know I made that mistake real early on wondering why it wasn’t working so good on the second joint and it is because I was trying to use the used section as could still see some copper colour 

[vk6zgo]

In addition to the remarks above, make sure the solder wick is fresh.  It has a limited shelf life (not weeks, probably not months, but somewhere in the small number of years).  Adding flux sometimes will restore it, but sometimes not. 

Good contact between the wick and the solder is important.  Pressure helps on this, but as has been noted this can result in pad damage.  Practice on something you don't care about to figure out the right balance between wick effectiveness and damage to the pads.

Yes, years ago, at my old work, amongst the goodies which came with our Siemens TV transmitter some twenty years before, I found a small bonanza.

The Siemens 'scope probe & the trimmer tools were very useful, but the several rolls of desoldering braid were useless.
They were a top brand, but all those years had tarnished the braid enough that it just wouldn't wet.

it still looked nice & "coppery" but compared to new "El Cheapo" stuff from Dick Smith, it was quite noticeably duller.
We went through so much desolder braid that the stuff we bought new didn't have time to age, but I have noticed since I have been using it much less intensively, that braid that is even a few years old is pretty hopeless.

These days, there is always the possibility of somebody buying a big roll of "time expired" braid & repackaging it as "a nice little earner".

[radar_macgyver]

Chemtronics makes several versions with different types of flux, and they also make a type with no flux. This requires you to add your own. I bought some of the latter by accident and it took me a while to figure it out. Also, improperly stored wick can tarnish - Chemtronics sells them in a sealed bag to protect against this. I store mine in a ziplock bag (gotta do something with the million bags that Digikey sends me on each order!)

[Dan123456]

gotta do something with the million bags that Digikey sends me on each order!

Sorry for going off topic but, my god, don’t they just!!! Bags inside bags inside bags 

Plus they are all good quality so would feel bad chucking them so I just have a giant bag bag but for my DigiKey bags 

[humidbeing]

Wow this kinda blew up while I was busy, lmao. I will get you guys a video of me trying to wet the braid directly with my microscope tonight (US time).

Chemtronics makes several versions with different types of flux, and they also make a type with no flux. This requires you to add your own. I bought some of the latter by accident and it took me a while to figure it out. Also, improperly stored wick can tarnish - Chemtronics sells them in a sealed bag to protect against this. I store mine in a ziplock bag (gotta do something with the million bags that Digikey sends me on each order!)

I too have a huge bag of little mouser baggies. But poly bags will not keep out moisture. Put one of those humidity cards in one and they will quickly turn pink. That's why Mouser puts humidity sensitive components inside those metalized plastic bags.

[Snowycage]

Keep your hand oils off the braid too. Just helps. Not the game changer. The other part that helps is getting the wick hot before you go to apply it. It needs to be pretty darn hot before it will start to do it's job. That means up and down the wick. The single spot you're heating isn't going to wick as much as more of the wick heated.

[humidbeing]

Ok so if I cut a small piece of braid I am able to tin it with a chisel tip at 370 C. So I guess my TS80P just can't handle heating up the whole role, the copper trace, the component, and the solder joint all at once.

[xrunner]

Ok so if I cut a small piece of braid I am able to tin it with a chisel tip at 370 C. So I guess my TS80P just can't handle heating up the whole role, the copper trace, the component, and the solder joint all at once.

That's what I thought at the beginning. Not enough heat. Nothing else is wrong.

https://www.eevblog.com/forum/beginners/solder-wickbraid-what-am-i-doing-wrong/msg5220942/#msg5220942

[tooki]

Solder wick is, compared to a typical solder joint, a huge mass of copper. So it will require more heat (≠ higher temperature!!)* to work properly. This means a few things in practice:
- use as large a tip as possible. The larger thermal mass will enable you to pump in more heat without having to increase the temperature (which is damaging).
- make sure everything is impeccably clean. Every layer of oxides, be it on the tip, or tarnished solder, or tarnished wick, reduces heat flow. So clean and re-tin your tip every time. Reflow old, tarnished solder joints with fresh solder before attempting removal. Discard old wick. Flux helps, but is no substitute for proper preparation.
- cut off the piece of wick instead of using the whole reel. This limits the thermal mass of the wick. Use tweezers to grip the cut piece because it will get too hot to hold by hand.
- ensure there is a good thermal bridge on your iron: this means having a good dab of fresh molten solder on the tip. More specifically, this dab of fresh solder needs to be on the side of the tip that you will apply to the wick.
- paradoxically, you may need more solder in order to make it absorb well. The solder improves thermal conductivity.
- use a tip shape that allows you to apply a flat side of the tip to the wick. A chisel will work but has to be held at a shallow angle; angled tips (the kind that are basically a cylinder cut off at an angle) work very well. Conical tips suck at this job (as they do for most jobs IMHO.)



*while a higher temperature is one way to push more heat into the joint/wick, it’s not the only way, and is usually not the best way. That’s why I indicate that they aren’t the same thing.

[Psi]

yeah, I was going to say.
It was either going to be not enough heat, or fake solder wick.

Though normally the fake solder wick does work ok if you add your own flux.
So, yeah, lack of heat is the one.

Your iron maybe lying to you about the actual temp due to being way out of cal.
Or maybe just underpowered for some reason. If its a TS80 you sometimes supply your own PSU for it.
Are you sure your PSU can pump out enough volts/amps to fully run the iron at its full potential?

I did wonder for a sec if maybe your iron was in F mode rather than C.
370F is like 190C which would melt lead solder wire if you touched it to the tip,  just , but would be totally useless to do any actual work with. 
But that's probably unlikely to be the issue. If you have used your iron to solder anything at all then it's not running at 190C.

[fourfathom]

FWIW, used or unused solderwick makes a good ground connection on your RF circuit prototypes.  It's got a really low RF impedance due to the geometry, similar to copper tape or strap.

[humidbeing]

I'm using the official USB-C PD PSU that comes with the TS80 kit. I've never had an issue soldering with it before. Have had this iron for a few years now.

However, those of you that mentioned calibration may be onto something. I have noticed I must set this iron about 20 degrees (C) higher than all my other irons to get the same performance I'm used to.

[radar_macgyver]

Solder wick will have a higher than average thermal mass, so if your iron can't regulate its tip temperature well, it may cool down to below the solder's melting point. My current solder station (Pace ADS200) handles solder wick without issue. My old Hakko 888D would sometimes struggle, especially on larger pads. Also, thanks for the tip that the poly bags are not moisture proof. Their newer ones are labeled as having volatile corrosion inhibitors embedded in the plastic, that may help a bit. Maybe a Zerust tab in the drawer with solder supplies?