An example is similar to a Storekeeper trying to stack oranges and grapefruit in the same pile. Their structures are more complicated than those of pure metals because the two or more types of metal atoms have different sizes. An alloy is a homogeneous mixture of two or more metals. Also once the molten solder comes into contact with certain other metals (notably copper), chemical reactions begin that speed the flow of solder. This has the effect of lowering the melting point because the atoms can execute a phase change much more easily when not bound into a lattice structure. The alloy of tin and lead is not crystalline in structure, unlike most pure metals (and many alloys). tests, but it was in 1997 that I learned the Chemical nature (at Northern Telecom) of the Solder eutectic phase process. In 1979, the subject was actually on one of the C.E.T.
I was born in the year that the video was created, and was classically trained as a Technician with Lab time on the Soldering pencil and the Weller Gun. That the Human race without completely understanding Its simply one of those unpredictable quirks of nature Keep in mind though that American is my fourth language after English, Australian and 3:44] “…no one can tell you exactly why this happens But that was a long time back to.Īnd as a bit of tongue in cheek prodding of my American friends, this video proves that there is an “L” in solder. Most would suggest military as a hunch but I have seen many things in military that just would not be in any way acceptable in commercial. I can’t remember i it was commercial or military. This was in avionics from quite some time ago. The second purpose of the kicked up tail is that it would help any remaining oxides or contamination transfer to the soldering iron tip as you withdrew the soldering iron. HRS PCBs had teardrop shaped through hole lands and the component lead travelled along the bottom surface of the PCB towards the thinner end of the teardrop (even before soldering) and then had the tail kicked up at an angle and cut not far from that so that the tail passed through the whole solder joint and it was then an indicator that the solder had wicked through the entire path and the metal to metal contact (it was held that way with force during soldering) largely avoided the resistance of the solder and was less pone to heating and later dry joints. This makes me wonder when High Reliability Soldering (HRS) became a thing. Posted in hardware, History Tagged assembly, nasa, soldering, space race, vintage Post navigation Soldering is an important subject for many of us, we’ve covered the subject of solder metallurgy, as well as looking at how ancient hardware hackers soldered without the benefit of much modern knowledge. They call it too much of a science to be called an art and too much art to be called a science, and we can sure appreciate that.Īs you would expect (and it’s not exactly a big secret) NASA has some very exacting standards for assembly of all hardware, like this great workmanship standard, which is well worth studying. The bottom line in all this is, is that the work must be as perfect as is possible, as there is very little chance of sending someone up to fix a dodgy soldering job, once the assembly is hurtling around the planet. They even specify how much to wrap a wire around a terminal to be soldered, never bending the wire more than 180 degrees. When soldering a pre-tinned wire to a leaded component, a clamp is required to prevent movement of the wire, as is a thermal shunt on the component lead to protect the delicate component from excess heat.
The road to the Moon is paved with calibrated wire strippers. If they did have to use a cutting-type stripper, it must be precisely the right size for job, and calibrated daily. Of particular note are some of the details of wire stripping and jointing with components, such as the use of a hot-wire device to remove the insulation from wire, rather than use the kind of stripper we have lying around that cuts into the insulation and slightly distorts the wire in the process. The overall message about cleanliness couldn’t really be any clearer if they tried - it’s so critical it looks like those chaps in the film spend far more time brushing and cleaning than actually wielding those super clean soldering irons. This first one we’re highlighting here is a 1958 film about NASA Soldering Techniques (Video, embedded below), which has some fascinating details about how things were done during the Space Race, and presumably, continue to be done.
#VIRTUAL STRIPPER WALLPAPERS TV#
On YouTube has many old TV adverts and US government reels archived on their channel, with some really interesting subjects to dive in to.
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