Why are these so hard to solder ?

[netdudeuk]

So ...

eBay Chinese Arduino Nano - check
Pin headers - check
Fibre glass pen to clean pads - check
Flux pen (eBay cheapie) - check
Genuine Hakko soldering iron - check
Clean genuine Hakko chisel tip - check
MG Chemicals leaded 63/37 solder - check
Iron at 380 C - check

Failure to flow properly - check

I eventually got to the point shown in the photos but I had to really load the solder on, attack with the iron from all angles, use nice braid to take off the excess and at the point where all the pads had been wetted, add enough solder for tidy joints.

I've had the same with Pi Zero pin headers.

Why does it go this way ?

Everything else that I solder goes very well, smooth flowing and shiny joints.

[Rerouter]

at a guess your pin headers are slightly corroded and your flux isn't up to snuff, also 380 is way hot for normal solder, i rework must bigger beasts using a hakko 888 at 330,

[netdudeuk]

at a guess your pin headers are slightly corroded and your flux isn't up to snuff, also 380 is way hot for normal solder, i rework must bigger beasts using a hakko 888 at 330,

Yes, it could be the flux (as per my eBay mention).  That did still make a difference though.

I used to use eBay solder too and then tried the MG stuff.  It is infinitely better.  Same with solder wick.  So, I have considered better flux before but with shipping rules over here, we're talking an arm and a leg once a courier is factored in.

http://www.ebay.co.uk/itm/MG-Chemicals-8341-10ml-No-Clean-Flux-Paste-Syringe-/322189997186?hash=item4b04053482:g:vS0AAOSwpDdVa3Lj

I wonder if it would be worth it.

Regarding the pins, yes they look a little dull but the solder wasn't flowing on the pads, not the pins.

Thanks

[netdudeuk]

They also have this for the same price.  However, my pen tips get wasted when working with through hole component leads.

http://www.ebay.co.uk/itm/MG-Chemicals-Liquid-Rosin-Flux-835-P-Pensize-/222131634310?hash=item33b813c086

[Rerouter]

personally i have never used a fibreglass pen so i cannot speak for them, however based on your images the pads look to have reflowed fine,

One remark i will make is if you are using a hakko 888D (common one beginners end up with), make sure you read the manual and check its calibration, every few months another worker will try and set the temperature on that model and end up mis-calibrating the iron instead where i work,

the cheap thermocouple your multi meter likely came with is good enough for this task, lightly tin the tip then hold it against the iron and note the temperature, (you will likely be within 15 degrees or so)

[IanB]

I used to use eBay solder too and then tried the MG stuff.  It is infinitely better.  Same with solder wick.  So, I have considered better flux before but with shipping rules over here, we're talking an arm and a leg once a courier is factored in.

You're in the UK; surely you don't have to import things to obtain good quality? It must be possible to obtain good quality flux and solder from within the EU without hassle?

The MG brand is common in the USA, but I would not go to the trouble of having it shipped over from there if it is not marketed locally.

[CJay]

I've found the Chinese are able to manufacture packs of unsolderable pin headers, or at least headers that aren't easy to solder.

I use a Weller W60 (plenty of heat capacity, not heat, subtle difference) and genuine Ersin Multicore 60/40, the headers solder but not as nicely as the ones I buy from UK suppliers (even Maplin).

Weirdly, the headers that came with the Arduino Pro mini nano uno duo treize whatevero I buy from China always solder, so far, really easily.

[netdudeuk]

I used to use eBay solder too and then tried the MG stuff.  It is infinitely better.  Same with solder wick.  So, I have considered better flux before but with shipping rules over here, we're talking an arm and a leg once a courier is factored in.

You're in the UK; surely you don't have to import things to obtain good quality? It must be possible to obtain good quality flux and solder from within the EU without hassle?

The MG brand is common in the USA, but I would not go to the trouble of having it shipped over from there if it is not marketed locally.

I got the solder from Circuit Specialists who are also based in the UK.

Check out the screen capture to see where the cost gets so high.  I think that this is due to UK regulations.

£16.73 for a flux pen ?

[Rerouter]

try a tack flux syringe, they are about the same in costs, but you get far more milage, and it holds things in place at the same time.

[netdudeuk]

I've just compared an eBay Chinese Arduino Pro Micro with an Adafruit EZ-KEY, both plugged into the same breadboard.

The joints on the latter are all super shiny and beautifully shaped.  The Arduino joints are ok but not so good in both respects.

Maybe it is a combination of better pins and pad quality ?

[CJay]

Wow. Find a local source perhaps, that's a ridiculous handling charge, I can buy all manner of chemicals form eBay that need 'special' handling and the carriage isn't anything like that.

However, if you like, I will coil up a couple of metres of the 60/40 Multicore solder I have here so you can try it and post it to you if you PM me your address.

[sleemanj]

+1 on the cheap paste flux syringe.

Reduce iron temp a bit, 320 would be more typical, you might be boiling off the flux too fast.

That said I've always found headers a pita to solder generally speaking but lately I have been using a J type (aka hook, bent) tip and that makes for an easier job of it - orient strip perpendicular to you, start at the top, get the pin in the nook of the hook feed solder into it between the point and the pin, drop down to the next pin...

[CJay]

Oh, and just to add, unless I've been hot air reflowing SMD I've *never* needed more flux than that contained in the cores of the solder or paste.

[IanB]

I got the solder from Circuit Specialists who are also based in the UK.

Check out the screen capture to see where the cost gets so high.  I think that this is due to UK regulations.

£16.73 for a flux pen ?

I've no idea about that shipping and handling charge. That's crazy. I would expect a flux pen to be shipped within the UK in a padded envelope by first class post.

Also, I second the recommendation of Ersin Multicore solder. It's the best solder I have ever tried.

Try to find out from other UK forum members where they get their supplies from.

[CJay]

I've found the Chinese are able to manufacture packs of unsolderable pin headers, or at least headers that aren't easy to solder.

Never encountered unsolderable headers, as I only buy real gold plated ones.

I was kind of joking about unsolderable headers as I've not found any that wouldn't solder with some effort, the bag I got from eBay that are not easy to solder but as you say, the tinned ones and the gold plated ones solder really easily.

I'd not increase iron temperature unless I was using lead free solder, the flux in the 60/40 just burns and leaves an unholy mess to clean up.

[stj]

you have stacked mistakes here.

first you shouldnt use flux, because you have it in the solder and different fluxes can mess with each other.

second, you should use decent lead-free solder like Stannol TC with HS10 or KS115 flux in it.
(rapid sells it, and lots of fluxes and other good stuff)
https://www.rapidonline.com/stannol-ks115-sn99-cu1-rosin-free-halide-activated-synthetic-resin-solder-wire-520183

third, your temp is way to high.
i use 330 to solder with lead-free, if your temp is too high it will burn the flux and make things worse instead of better.
all fluxes have a maximum working temp - your iron is way over.

[Rerouter]

Why would you recommend lead free solder to a beginner? Its far more toxic and harder to use than normal leaded. ?

[stj]

where did you get that info from?

tin/copper is cleaner than tin/lead
the modern fluxes hardly fume, they pool as a liquid on the joint - none of that white smoke that leaded solder with rosin flux gives.

as for ease, if your temps are right, you wont notice any difference with tin/copper solder.

[netdudeuk]

Why would you recommend lead free solder to a beginner? Its far more toxic and harder to use than normal leaded. ?

Beginner ?  I got my first iron and built my first radio forty two years ago 

[Rerouter]

Sorry the nature of the question asked and the information provided led me to think that way.

[netdudeuk]

you have stacked mistakes here.

first you shouldnt use flux, because you have it in the solder and different fluxes can mess with each other.

second, you should use decent lead-free solder like Stannol TC with HS10 or KS115 flux in it.
(rapid sells it, and lots of fluxes and other good stuff)
https://www.rapidonline.com/stannol-ks115-sn99-cu1-rosin-free-halide-activated-synthetic-resin-solder-wire-520183

third, your temp is way to high.
i use 330 to solder with lead-free, if your temp is too high it will burn the flux and make things worse instead of better.
all fluxes have a maximum working temp - your iron is way over.

Thanks for the reply.

However, the solder wouldn't flow on the (burnished) pads until I'd used the flux pen.

I'd also say that the MG Chemicals solder is a decent solder.  It usually produces bright smooth joints, as per my comment above about the Adafruit boards with their own headers.

Here's what I use -

http://www.circuitspecialists.eu/leaded-solder-wire-roll-0-635mm-dia-454g-sn63-pb37-4884-454g/
http://www.circuitspecialists.eu/leaded-solder-wire-roll-0-81mm-dia-454g-sn63-pb37-4885-454g/

I work at 280 degrees C virtually all of the time but it wouldn't flow until I turned it up.

[netdudeuk]

Sorry the nature of the question asked and the information provided led me to think that way.

NP.  I'd probably put it down to a cheap board and (probably) headers too but I'm always interested in how others got on with things like this.

Here's an example of someone making a mess of soldering a Pi Zero.  I'd say he'd be better off with a proper iron with a better tip.

[netdudeuk]

Ok guys, so I took some eBay Chinese headers and an eBay Chinese FR4 board, used the same solder at 280 degrees C and used no additional flux.

Here's what I get, which I think is pretty reasonable given I've not even cleaned off the flux yet.  So, I'd say cheap headers can be ok.  Cheap Arduino boards are not so good.

[netdudeuk]

I'll just add that they just flowed.  I didn't need to move the iron from one side of the pad to the other or spend ages there with the heat.

[netdudeuk]

Ok guys, so I took some eBay Chinese headers and an eBay Chinese FR4 board, used the same solder at 280 degrees C and used no additional flux.

Here's what I get, which I think is pretty reasonable given I've not even cleaned off the flux yet.  So, I'd say cheap headers can be ok.  Cheap Arduino boards are not so good.

If one of the pins is connected to a huge ground plane without thermal relief, it could be a completely different story.

Agreed. However, in this case, it looks pretty much like for like.