What flux type for hand soldering?

I've never bothered with flux before, but as I'm going to attempt a Flat No Leads package I thought I'd better get some.

The choice seems to be between No-Clean Non-Corrosive type flux, and Rosin type flux.

Which is best for the 95.5% tin, 4% silver, 0.5% copper solder I'm using?

I'd rather use the Non-Corrosive type if possible, as my previous experience of solder with Rosin type flux core is that it munches through soldering iron tips at an alarming rate.

Thanks.

Interesting. Most of my solder is rosin core and I've never had problems with tips.

Solder paste (not flux) and hot air is used for a "no leads" package.
Not solder(wire) or a soldering iron.

Soldering iron tips last many years, even when used every day for several hours.
If they don't, you're doing something wrong.
Leo..

Maybe my tips are poor quality. I've always used a cheap 25W soldering iron for everything. The tip quality is probably not very high.

Is this a plain not temp controlled and not ESD safe "poker".
Then don't use it for sensitive electronics.
Leo..

QFN reflow without hot air

For larger SMDs I use 63/37 solder @.3mm thickness.
http://www.ebay.ca/itm/3mm-Rosin-Core-Solder-Wire-63-37-Tin-Lead-Flux-Solder-Welding-Roll-30-/262725183010?hash=item3d2ba42622:g:-igAAOSw5cNYL-FT

0402 are easily soldered with a stereo microscope.

1206 can be soldered why looking through head magnifiers X2 or X3

Use bent soldering tips like this:

Go through these 300+ posts for some hints.

Thanks for all the replies.

Maybe it would be easier with some silver paint? I've just remembered I have some of this in a tiny vial.

http://docs-europe.electrocomponents.com/webdocs/1513/0900766b815139bd.pdf

Learn to solder :slight_smile:

.

I used to work somewhere that had one of those high quality stereo microscopes. Sadly I don’t have access to that kind of equipment anymore. I don’t have hot air either, so it’s either silver paint or my cheapo, unrefined, 25W soldering iron.

I might just try the silver paint idea. The resistance looks quite low on the product datasheet, and it’s only for a quick prototype, so it doesn’t need to be a mechanically strong connection like I’d get with a proper solder joint.

And I never did get a reply on flux type …

PS. If anyone’s interested, I got the SMD to through-hole adaptor PCB via ebay from this supplier. Took me ages to find what I wanted, so I thought I might as well post it here for the benefit of others.

http://icstripboard.co.uk/

I use "no clean gel flux", generic brand. Works great.

These look neat Beedoo

Beedoo:
I've never bothered with flux before, but as I'm going to attempt a Flat No Leads package I thought I'd better get some.

The choice seems to be between No-Clean Non-Corrosive type flux, and Rosin type flux.

Which is best for the 95.5% tin, 4% silver, 0.5% copper solder I'm using?

I'd rather use the Non-Corrosive type if possible, as my previous experience of solder with Rosin type flux core is that it munches through soldering iron tips at an alarming rate.

Thanks.

Never ever ever use plumbers flux for electronics! Its extremely acidic and destroys PCBs.

Rosin flux is what you want.

By the way if you just search the web for "solder paste" you normally find plumber's solder paste,
which is not what we mean by solder paste. Don't make that mistake either. If its cheap its
probably the wrong sort too!

I use Chip Quik no-clean lead-free paste. Don't make the mistake of buying lots of solder paste,
it has a finite shelf life (it dries out) and should go a surprisingly long way unless you are manufacturing PCBs.

BTW Rosin is not in the slightest corrosive or bad for soldering bits - you have either a plain
copper bit (useless), or you've used abrasive on a tip to clean it and worn through the very thin
iron-plating on the surface (rendering the bit useless - solder dissolves copper quickly, but
not iron at all).

I use "no clean gel flux", generic brand. Works great.

Any links?

Update:

I mounted the SMD chip on the icstripboard adaptor using silver paint. It took me two goes as the first time I used too much, so the paint spread out under the chip and shorted some of the pads together. You only need the tiniest smear of silver paint on each pad.

Interesting. Not sure I'd trust paint for the power connections but for signals its probably fine.

MarkT:
Interesting. Not sure I'd trust paint for the power connections but for signals its probably fine.

It would make for an interesting experiment on more power-hungry devices. The datasheet says the resistance is very low, and I believe silver is a better conductor than copper, although I appreciate there's some kind of glue in there too. In my application it doesn't matter, because the chip only consumes a few mA, and the other pads are digital I/O.

Search for TOPNIK TK83 or TOPNIK LP-1,I tested them both and I promise you won't be sorry it you get them,they are great for fixing low quality solder.TK83 one is much more sticky and you might have to clean PCB with acetone or something and also TERRIBLE smell when touched with iron tip.LP-1 one is great,almost no smell and it doesn't leave sticky marks.They last really long.As I said,perfect for fixing bad solder.Put solder on tip for 10 minutes and try to solder,you will se that it doesn't flow,this flux is made to fix this.

Hello guys,

I personally use CS-FLUX in the last three years and I don't have any complain.I fyou want tho give a try a youtube-video named ''ATI GPU removal with the help of CS-FLUX'' will be very helpful

Beedoo:
I'd rather use the Non-Corrosive type if possible, as my previous experience of solder with Rosin type flux core is that it munches through soldering iron tips at an alarming rate.

Nothing about rosin is corrosive. Sounds like you had tips that weren't iron plated! Bare copper dissolves
in solder quite quickly, the tip must be iron plated (iron doesn't dissolve in tin). Damaging the iron plating
on the tip will sentence the tip to an early death, which is why you need to treat the bit with care (no
abrasives, don't bend it or file it, don't let oxide build up on the iron coating (black iron oxide is really hard to remove)).