Soldering flux recommendations

I think pretty much all flux is lead-free.

But, try this (some of the items are flux remover):-

Best regards, Spehro Pefhany

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"it's the network..."                          "The Journey is the reward" 
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Do you mean flux or solder? Or do you mean tip cleaner?

Like Spehro said, flux itself is going to be lead free unless it's been contaminated.

--
Tim Wescott 
Control system and signal processing consulting 
www.wescottdesign.com

Youtube has pictures!

The flux is lead free but flux for lead-free processes is different than flux for leaded processes.

BTW, "lead free" and "easy to work with" don't ever belong in the same sentence.

I use ordinary plumbing flux for lead-free plumbing[1] applied with a toothpick or small brush. It works very well for prototyping, a small tub will last for years, but I guess it wouldn't be approved for manufacture.

[1] You can't have lead-free 'plumbing'. Plumbers should now be called 'tinkers' and what they do, 'tinkering'.

Cheers

--
Syd

On a sunny day (Fri, 22 Feb 2013 11:30:29 +0000) it happened Syd Rumpo wrote in :

The ordinary 'plumbing' flux here is called S39, it is extremely agressive and should not be used on electronic components.

I repeat ****NOT**** for electronic components.

Yea, that is what everybody does, even designing trains and plane.

This is what I use, and I've been doing so for years...

...yes it's aggressive and, like I said, not for production. For prototype building and rework it's really very good indeed.

Cheers

--
Syd

On a sunny day (Fri, 22 Feb 2013 13:20:03 +0000) it happened Syd Rumpo wrote in :

In case of the S39 it was the long time effect, I remember from long ago, I soldered some Phlips 'tar' capacitors with it in a radio as repair for someone. The radio started making cracking sounds after a short while.... I expect the effect on SMDs to be even stronger. Not sure what it does to very expensive plated soldering tips either. Why take chances, special flux is readily available for al sorts of things I even have a flux-pen (looks like a marker) for soldering strips on solar cells.... :-)

cells....

The stuff I use doesn't affect the soldering bits at all, as far as I can see. I use it because it's so good, and better than the pen stuff I've tried. The manufacturer describes it as a 'medium active' flux. It's a colourless translucent paste.

A quick wipe of this over SMD legs and solder wick becomes almost magical in its suckiness and the solder flows like mercury.

But again, not for production.

Cheers

--
Syd

If you guys are having a problem with "prototype building and rework" having a need for an aggressive flux, then you have serious component age issues.

Snip back the first inch of any cable you have which you intend to use to fabricate an interlink with. If it is old cable.

Modern soldering is easy, and I have never seen the need to use any such aggressive flux to wet a connection.

Either the wire is too old, or your understanding (lack of) of thermal masses is lacking, or both.

I have found that silver plated mil wires and cables are far easier to work with than tin plated stuff.

Tin plated HV cable acts like it was coated with ultra-ever-dry. Very hard to wet, but still doable. I always spec the SPC stuff.

I have some *nickel* plated mil spec telfon (mineral loaded, high temp) wire. It takes for damned ever to tin the stuff. It's also about 10AWG.

Tim

--
Deep Friar: a very philosophical monk. 
Website: http://seventransistorlabs.com

I bought a quart bottle of RA flux (one shade more aggressive than RMA) that I use in a needle bottle. A quart will last me the rest of my career, I expect. Good medicine, especially for old oxidized parts.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC 
Optics, Electro-optics, Photonics, Analog Electronics 

160 North State Road #203 
Briarcliff Manor NY 10510 USA 
+1 845 480 2058 

hobbs at electrooptical dot net 
http://electrooptical.net

This is water-based, and is probably tinners flux (acid).

Plumbers flux is grease-based. Before I knew any better, in the early

1960s, I built a Heathkit VTVM using plumbers solder and flux. The VTVM worked just fine, and actually still does - I fired it up just to see a while ago.

Joe Gwinn

Funny, I just did a little maintenance on my V-7A. Replaced the PS diode (encapsulated Se), filter cap (no sign of trouble with either, just wanted to change them), and AC coupling cap (molded axial, the kind that sometimes goes bad), and calibrated it so it's within a few percent again on most ranges. Still needs some Deoxit on the switches, and fresh oil in the movement, but it's reasonable otherwise.

One advantage of this unit over most DMMs is the AC bandwidth -- it's flat out to about a MHz, probably further with transmission line (I've got stray banana jack cables going to it and see some zeroes in the MHz band). Most DMMs I've seen roll off at a few kHz, not even enough for audio applications! The manual warns that, although it may work out to 7MHz or so, the loading will be significant up there.

Tim

--
Deep Friar: a very philosophical monk. 
Website: http://seventransistorlabs.com

Hmm. I looked and found my Heathkit RF signal generator instead. I'll have to find my VTVM and see what it's model number is.

Yeah. My DVM is good to 20 KHz or so.

Joe Gwinn

ng cap (molded axial, the kind that

t

You might increase the size of the AC coupling cap. As built the AC bandwidth is not flat down to 60 hz.

Dan

You're not supposed to tin it. You're supposed to crimp it with a really expensive tool.

Best regards, Spehro Pefhany

--
"it's the network..."                          "The Journey is the reward" 
speff@interlog.com             Info for manufacturers: http://www.trexon.com 
Embedded software/hardware/analog  Info for designers:  http://www.speff.com

I'd noticed that. I calibrated AC at 600Hz. It drops off noticably by only 100Hz, so the 120V line is only "100V". Don't think I have any 0.1

1600V handy though (it uses a 0.01).

Tim

--
Deep Friar: a very philosophical monk. 
Website: http://seventransistorlabs.com

by

1

If you paralleled the 0.01 with another that size , it would help a lot. Should move that drop at 100 hz to 50 hz.

I have a few 1 ufd 2100 volt caps in my junk box from junked microwave ovens, but I do not think one would fit inside the case.

Dan