NOKORODE

I want to open by stating that Nokorode® is still manufactured today. But do not take this as a product endorsement. This is a product more than a century old, so there's a lot of history to cover.  In their ads in 1913 the listed off their customers: New England Telephone & Telegraph, The D&W Fuse Company, The Johns-Pratt Co., The Sachs Co., and the Bryant Electric Company.  By 1920 it was Cadillac, Studebaker, Buick, Dodge, and Ford. More here and here.

It was originally made by the M. W. Dunton Company based at 65 Atlantic Avenue Providence, RI. It was bought out by the RectorSeal Company in 1998. It was an oil-based flux that supposedly also sealed solder joints against corrosion which they also sold as "soldering salts" in powdered form. The labels always read that it was patented in 1903. But what we find in the Official Gazette of the United States Patent Office from May 23rd 1903 is a patented "Label." It's Number 10,101, granted June 16th.

The paste was sold in tins, glass jars and more recently plastic buckets. On eBay I found a glass bottle of Nokorode flux. The wording and packaging indicate it was more of a liquid than a paste. It bore the following labeling:

"Nokorode flux will not deteriorate with age. takes the place of all other soldering fluxes, making it necessary to use only one flux for all kinds of work. Use this solution also as a dip to clean and tin soldering iron as well as a flux for the work. Do NOT use Sal Ammoniac."

That last bit is interesting. Sal ammoniac (aka salmiac), is a naturally occurring mineral composed of ammonium chloride (NH4Cl). It is the product from the reaction of hydrochloric acid and ammonia.  Today it's a common fertilizer. A hundred years ago it was also commonly used to clean the soldering irons used to make stained-glass windows. You can still buy it today, usually sold as a "tinning block." Why would we not want to use that with Nokorode?

Well Nokorode doesn't list the ingredients but the MSDS warning tells everything we want to know for this question. It says that Nokorode is lead-free (may not have been so in 1903) and "Contains: Zinc Chloride (ZnCl2) and Ammonium Chloride. Precautions: May cause irritation to eyes."  Nokorode already contains Sal ammoniac!   Note, that when that mixture is heated with a soldering iron this could produce fumes of zinc, chlorine and hydrochloric acid (HCl). These are all irritants. The ingredients of Nokorode turn out to be (mostly) petroleum jelly, zinc chloride and ammonium chloride.

So that also reveals why their instructions advise against using Nokorode on electronics. Both HCl and zinc chloride, (the actual flux agent) are corrosive to metals. That may not matter on a stained glass window with a thick metal joints, or automotive parts. But circuit boards and component joins are very thin, and more easily damaged by something with any corrosive effect on electrical connections. That's ironic. What's the anti-corrosive ingredient?  Probably the petroleum jelly.

200 years of Solder

In August of 1842 a patent was granted to a brass-founder, William Raybould of St. James's Walk, Clerkenwell, in the county of Middlesex, for "a new or improved soldering iron." The patent record went on to note excitedly that it used screws instead of rivets:

"In the ordinary mode of making soldering irons the copper head is fastened to the shank by means of rivets...  the patentee employs screws to fasten the copper head thereto, in place of rivets as heretofore, the object of which is to facilitate the removal of the head when required..."

Hot fusible metal solder has been around longer than home electricity. American Beauty brand soldering irons have been made since 1893 after a debut at the Chicago fair. That same year the American Electrical Heater Company of Detroit Michigan began manufacturing electric soldering irons. General electric may have been makling them as early as 1910. [SOURCE] Soldering irons have been around forever. I found a reference to one in an article on "Steam-carriages" in a section on "The Art of Coach Building" from 1833. But if you go back much further the term "soldering" is used in applications we'd now call welding. But I did find common lead solder described accurately in an 1819 edition of The Cyclopaedia

"The soft solder is composed of three parts of zinc and one of lead, and is applied by means of a common soldering iron, made red-hot. Solder for tin is made of two-thirds of tin and one of lead"

I read today that Prof. Hanchen Huang and Paul Elliott of Northeastern University along with Prof. Stephen Stagon of the University of North Florida have founded a company that makes a metallic, conductive adhesive process they call Mesoglue. This will allow parts to be connected on a circuit board without heat a change which will permit the manufacture of "press-fit" electronics. As you know even today the heat of the soldering process sometimes damages delicate components like semi­con­ductors and solder can be applied unevenly.Temperature changes can break these weak connections and cause failures... even fires.  More here and here.

Their glue is made of metallic nanorods which are very tiny rods with metal cores coated with indium on one side and galium on the other. These coated rods are arranged along a sub­strate like angled teeth on a comb. In the glueing process they inter­lace these teeth. When indium and galium touch each other, they form a liquid then the metal core of the rods acts to turn that liquid into a solid.

To Solder with Fire

If you can solder with fire, you can solder with impunity.

Hacked Radio Guitar Amp

Apparently this is a thing. I was listening to the Legendary Guitar Amp Tape and noticed a slew of these hacked radio videos on Youtube. Strangely most of the videos are from the UK, and most of the results are pretty awesome. I'm pretty tempted to get out the soldering iron right about now.

Solder Joints

It is very easy to solder poorly. A bad connection can under-perform and you might get away with it. You might also start an electrical fire or burn out a board component. A bad splice increases resistance. You can have high-quality, well-maintained tools, proper parts and still get a poor connection if you don't know how to solder the damn connection properly.

There are self-taught engineers have will suggest some electrically unsound connections. I am no expert, but I know how to execute the basic four splices. You need to know them all:

1. Temporary Hook Joint
This joint is made without the aid of solder. It's a temporary joint used in testing or or you feel like living dangerously.  Band one wire over another to make the first hook, then repeat the process. To tighten you can gently compress the hooks with pliers.

2. Bell Splice
This is the most common splice you'll see. It's behind every electrical plug in your home. With heavier guage wire such as that case just strip the wires to the same legnth and grip the ends with lineman's pliers and twist them together. For a temporary connection put on a nut, for a permanent connection brush with flux and then solder.

3. T-Joint
This splice is used to connect a leg to an unbroken lead.  First you strip away an area of insulation from the lead. Then twist the new wire around it. With stranded wire there is the temptation to divide the wire into a "Y" and braid it in two directions. This is unwise. The crook of the Y can arc if there is a void and resistance will likely vary between the two sides of the leg.

4. Western Union Splice
This is only for the truly hardcore. (See below) This complicated splice is also called the Lineman's splice.  The complicated wrapping pattern actually tightens when pulled which is why you usually see it only with wires under tension. This is probably why it was developed for the telegraph. It's description in the NASA guide describes it as stronger than the unbroken wire. Just note that it is only intended to be used with solid rather than stranded wire.

How To Solder

This is a great and simple instructional on soldering.