An arc welder in the datacenter: What could possibly go wrong? Yet again Monday is upon us, bringing the prospect of another working week filled with joy, opportunity, new horizons, and a fresh dose of Who, Me? – The Reg's weekly confessional in which readers share stories of jobs that had promising beginnings, and … interesting ends. This week, meet a reader we'll Regomize as "Andrew" …
Have you ever assumed a skill would be easily acquired?
No, but assumed a skill would not be lost. Recently, an electronic appliance started to malfunction, i.e. some relay didn't switch any longer. Having been fully trained to know my way around electronics, I went on with fault diagnostics. And I duly (dully!) fried said appliance, beyond repair.
safety goggles ->
My temporary apprentice and I both had a go at a small spherical teaching robot the next door primary school asked us to look at. I did quite a bit of connection testing. Then turned it on and it was working again. To test a connection with the ohm meter the tester puts a small current down it. This can flip things so I presume it flipped something enabling the thing to work again.
We presented it back to the school and they were very grateful. Schools are not overly funded so replacing things is often difficult. I keep the science dept at the secondary I work in functioning as well as advising when something is beyond repair. I also fix stuff for music. I’m a dab hand with electronic keyboards and electric guitars now.
Shifting the blame for a cock-up is of course par for the course in these situations. It's a bit rich to shift the blame to someone who did a similar job competently and wasn't anywhere near.
The story also brings back memories of the time I was teaching someone to solder electronic components onto a circuit board, but they kept referring to it as welding. I would certainly not recommend welding to attach even the more robust triacs (380V, 32 A, TO-48 housing) used for a theatre dimmer to any circuitry, so just to drive the terminology home, next time they said they were going to weld a component to a practice circuit board, I couldn't resist going "KZZEERRT" as the soldering tip touched the component. Gave them quite a shock, but they did find it funny. Their soldering was actually pretty neat.
No, welding and brazing/soldering are two completely different processes.
"due to its tendency to take a Germanic word and its equivalent French word and give them subtly different meanings."
This isn't actually a thing. People doing folk-semantics invent subtly different meanings for words that mean the same thing, assuming there must be some difference. 'Flammable' and 'inflammable' is a good example in this context, because they aren't even from two different roots.
> No, welding and brazing/soldering are two completely different processes.
> "due to its tendency to take a Germanic word and its equivalent French word and give them subtly different meanings."
> This isn't actually a thing. People doing folk-semantics invent subtly different meanings for words that mean the same thing, assuming there must be some difference. 'Flammable' and 'inflammable' is a good example in this context, because they aren't even from two different roots.
Throw in the French "ininflammable" for added confusion.
You may find this bit of history quite relevant (read: you're right - and this guy has many, many examples of it).
Quite a coincidence I came across it a few days ago, very interesting.
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There are quite a few interesting dualities in words. There's a Wikipedia article listing many of them: List of English words with dual French and Old English variations
> Beef is derived from the French word for cow, but in English refers to cow meat.
Surely...
"Beef" is derived from bœuf, the French for ox and also for beef, itself derived from the Latin (for ox), bos or bovem.
The French for cow is vache, also derived from Latin (for cow), vacca.
If you were poor, you probably spoke Anglo-Saxon; and you might breed sheep, or weld large chunks of iron together, for a living.
If you were rich, you probably spoke Norman French; and you might pay someone to bring you a plate of mutton, or solder you up some silver or gold jewellery.
Unfortunately the original post leaves out the "test of the story."
Weld and solder have the same base word, "soldadura," but add more description that also includes brazing, "fuerte/blanda."
I have MIG/TIG/Arc electric welders, & Oxy acetylene welding equipment and even have a small plastic welder, as well as various soldering irons. We all use specific words when discussing "welding" in English, as do Spanish speakers.
For specific examples, see: https://es.airliquide.com/soluciones/soldadura-industrial/cual-es-la-diferencia-entre-la-soldadura-fuerte-y-la-soldadura-blanda
I believe it was Henry Watson Fowler (the great English lexicographical genius) who wrote "solder without the "L" was the only pronunciation I have ever heard, except from the half-educated to whom spelling is a final court of appeal ... " and was baffled by the OED's statement that it was the American usage.
As the OED puts it (paraphrasing to avoid copyright hissy-fits): The modern form in English is a re-Latinization from the early 15c. The loss of the Latin L in that position in Old French is regular, as poudre from pulverem, cou from collum, chaud from calidus.
@Jake
I wonder where the OED got its information.
In shop class in 1968, we learned to solder, and we did not pronounce the 'l'. This was in a suburb of Cleveland, Ohio, a region as blandly Midwestern as one can find. I have since encountered many Americans who can actually solder well, and I have heard none of them pronounce the 'l'.
Unknown powder lab contents reminds me of the time I went in on a Saturday morning and found the door had been jemmied and the big bottle of ether nicked. The cops found the culprits passed out on the ether in the next building (connected by a bridge).
When the boss came back from his sabbatical he was told about it, he then exclaimed “the cocaine!” and rushed off to check the plastic Petri dish which had been sitting on the electrical trunking behind the microscope, unlabelled. The get off your head kiddies had walked right passed it to get the ether.
So there can be advantages to not labelling ALL the white powders.
The cocaine was there because the boss had bought it from Sigma as you could do back then. He used tiny amounts in experiments trying to work out how it acted as a local anaesthetic. The rest of the 10g or so of lab pure cocaine just sat in the dish.
It's probably the same word in all the Latin languages ( French, Spanish, Portugese, Italian, Romanian, ... )
I know for sure it's the same word in French and the difference is made by the context ( like tusing erms like specifying arc welding or soldering iron... )
Welding and soldering are two different processes, so I doubt English is the only language to distinguish them linguistically.
Soldering is to join two items (not necessarily the same materials) by heating the joint between them high enough to melt a second (or third) different material which is then introduced to the joint which melts and holds them together. The original material/s to be joined do not get hot enough to deform.
Welding heats objects (usually of the same material) hot enough for them to melt and flow into each other.
Not sure what brazing is, I think it's a variant of soldering somehow.
Brazing is where the filler and temperature is high enough that there i a significant amount of mixing of the base metal(s) to form a new alloy. Done right you can start off with a filler that is no longer present in the joint and a joint strength significantly higher than the filler material.
Yes, the base metal can 'melt' in the presence of fluxes (the filler can also act as a flux) that is a lower temperature than the base metal bulk melting temperature.
""Welding" and "soldering" is the same word in Spanish, and I wouldn't be surprised if English is the only language that distingushes them, due to its tendency to take a Germanic word and its equivalent French word and give them subtly different meanings."
It can be important to distinguish between soldering, brazing and welding. It can even be important to differentiate between the various sorts of welding. It's like people saying "loctite" when they mean "threadlocker". Loctite makes all sorts of adhesives and I've repaired items for another manufacturer where they told an employee to use "loctite", so that employee went in the fridge and got a bottle of cyanoacrylate (Super Glue). It said Loctite on it. They might have grabbed some epoxy as well, but that wasn't keep in the adhesive fridge. 242 is much different than 406.
"Superglue will work as threadlocker"
It did. Very permanently. The problem was it was very thin and ran through the mechanical device and the moving bits wouldn't move any more. I don't remember if there was an issue with "blooming" too where you get a frosting from the fumes of the super glue.
In many languages, the same word is used for both "soldering" and "welding". After all, it's more or less the same process: creating new metallic bonds by allowing a molten metal to solidify in contact with a solid metal.
Modern English was basically created from two languages -- the Norman French (of Romance origin) spoken by the aristocracy, and the Anglo-Saxon (of Germanic origin) spoken by the peasantry -- crudely merged into one. As a consequence, you get these not-quite-synonyms all over the place (such as some animals being known by different names depending whether they are in a field, being raised by a common farmer, or on a plate, being consumed by a nobleperson) where words entered from different directions.
Similarly, the aristocracy would have had one word for joining together small pieces of precious metals for jewellery; while the peasantry would have had a different word for joining together large pieces of common metals for things like tools, horseshoes and door furniture.
This is completely wrong. Soldering and welding are very different processes with very different results. Soldering/brazing is basically using an easily melted metal as glue; welding is joining two pieces of metal into one.
And I explained above why the not-quite-synonyms thing is wrong. It's folk-semantics: people assume there must be different meanings for synonyms, and then invent imaginary differences. The pairs of words are often there because of the two-languages thing, but not always.
"welding is joining two pieces of metal into one"
And, of course, the original technique is fire welding where no new material is added - the two pieces are heated in the hearth to such a temperature that they can be beaten into single piece by a smith wielding* a hammer.
* Back to the amateur etymology - is this the origin of "weld"?
> And, of course, the original technique is fire welding where no new material is added - the two pieces are heated in the hearth to such a temperature that they can be beaten into single piece by a smith wielding* a hammer.
In Adrian Tchaikovski's excellent novel 'City of Last Chances', the protagonists plan to engage in an industrial action, which (to the consternation of their bosses) they refer to as "wielding the hammer"; This phrase is said to derive from a local proverb "Sometimes the most effective way to wield a hammer is to put it down" - they are going on strike.
Oh come on, is this your first day working in IT?!
The golden rule is, "Last person standing next to or known to be near X is instantly responsible for any faults or issues, until another mug and/or idiot can be found to stand near X when it breaks again.".
... I'm here to tell you that you don't just fire up and use an arc welder after it's been sitting around doing nothing for a few years. Such equipment attracts rodents, reptiles, avians and insects, all of which do their own particular damage. The worst is rodents which gnaw on everything, and then pee all over it, just to make sure it's completely toast.
On top of that, after sitting around for a few years, the cables will have gone walkies, there would be no stick/rod to be seen, and all of the other little bits & bobs would be similarly missing. Including the helmet, which I heartily endorse for arc welding.
And then we get into the damage caused to the old-school data center. Drives would have been crashing left and right for weeks because of the shit that welding kicks onto the air, tape read/write heads would get trashed, etc. etc. One quite simply doesn't weld inside a datacenter, not without precautions ... and the story about that is a tall tale unto itself. (Picture a two-layer "shed" made of 10mil clear visqueen, with it's own HVAC and filtration, built around a rather monstrous (but broken; forklift accident) iron casting that was used to measure particle location after running the beam through an experiment at SLAC ... ).
Other than that, cool story, bro.
[Voice of Sean Bean] "One quite simply doesn't weld inside a datacenter"
But rodents near the stock exchange's data centre? I'd assume they'd have bigger problems than a non-functioning welder. And if it wasn't near the dc, it's highly unlikely that someone would have found it in the first place.
"they had been sitting in old barns and disused automobile repair stations."
In Silly Con Valley, I've found them inside the chain-link outdoor storage area for gas bottles, and under the pile of crap that always seems to turn up in a corner both inside and outside (just off the dock) the shipping and receiving department; likewise the stockroom. Also the basement room that the heavy goods lift decants into. Etc.
"But rodents near the stock exchange's data centre?"
You've obviously never been to a big city. Rats are ubiquitous wherever filthy, wasteful humans congregate. I have literally seen rats run across the trading floor in New York. I don't think I've ever seen a financial district data center that didn't have rat poop under the raised floors ... and sometimes on top of the equipment itself.
Peripherally related to this item:
Many years ago a chemical plant had a scheduled shutdown for maintenance and the installation of some steelwork, by welding. When they wanted to start the plant up again they discovered that the stray currents from the welding had burnt out a rack of instrumentation, which took several weeks to replace :( Very costly loss of production.
When arc welding you have to connect the ground/return close to the point where you are welding. If you use long cables and have a considerable distance between the grounding point and the welding point you can get nasty stray currents. And I imagine the long welding cables carrying a high current could also induce current in nearby cabling.
Apparently any further extensions of the steelwork on that plant were done with bolts or clamps, not welding.
When I was an apprentice, at the Apprentice Training School in Harold Hill, one of my fellow apprentices burnt a hole in his chest. We were gas welding, and a blob of molten weld metal burnt a neat hole through his tie and shirt, and lodged itself against his skin. He couldn't get undressed quickly enough to prevent a bad burn to his chest, and had to rush, topless, across the car park to Sister Amos in the Medical Centre for remedial action.
And I wince at the memory, "a few years back", overhead welding on the farm ... wearing wellies of course. Some may already be ahead of me, but a large blog of molten steel dropped down the front of a welly where it was nicely searing itself into my foot. Of course, getting the welly off resulted in pressing the molten blog harder into my foot so it's hard to know whether I would have suffered less by not taking the welly off.
'It was started by stray sparks from a welder'
Isn't that what set off the explosion in the port warehouse in Beirut?
Welding sparks start fire in rubbish which sets off some fireworks, which light a load of diesel, which sets off 3000 tonnes of ammonium nitrate. As far as I remember reading.
See also, using an angle grinder, on top of a tank holding sewage.
"Welding sparks start fire in rubbish which sets off some fireworks, which light a load of diesel, which sets off 3000 tonnes of ammonium nitrate. As far as I remember reading."
It was something like that. On top of all that, the AN was improperly stored after being confiscated some time back as part of an improper shipment (too big of a quantity in one place/ defective paperwork?) Nobody knew what to do with all of that fertilizer so the easiest thing was just to leave it there and ignore it.
Reminds me of when rigger boots were banned in many industrial situations: one reason was that weld sparks could drop in them and cause burns (not to mention uncontrolled and potentially unsafe movements) - not a risk if your flame-retardant coveralls were over them, but people had a habit of tucking them into their boots...
They're also not so safe just as industrial footwear because they have to be loose enough to slip on and off.
> They [rigger boots]'re also not so safe just as industrial footwear because they have to be loose enough to slip on and off.
Rigger boots have the disadvantage that they might slip off, especially if they get caught in machinery. Lace-up safety boots have the disadvantage that they won't slip off, especially if they get caught in machinery.
We had a very similar incident. While installing a brand new, shiny, robotic plasma system, a welder was working on the platform. Originally he had a mechanical ground, metal pipe set against another part of the frame 20' away and leaning against a steel column. The plumber came by and moved the pipe and the welder didn't notice. The main breaker for the machine blew and we couldn't figure out why so we opened up the wiring junction box. It was a melted mess and we could see smoke coming off the ground lead while the welder was still working. Even with a ground pin wired to the machine frame, the current found the easy path up into the control cabinet and out the mains ground. VERY luckily it just blew up the connector to the cabinet leaving shrapnel inside instead of the robot controller.
The welder still works here, but he about had that mechanical ground pipe used as a popsicle stick with him on top. He also got a few 'days off'.
"Really, how hard can welding possibly be, right?"
Welding in and off itself, just getting a basic, functional weld, isn't really all that hard. You could teach a child to do it. In a lot of situations, people care too much.
That said, knowing when to attempt a weld, what precautions to take, whether you need pre-heat or post-heat on that particular material, whether a material is weldable with what flux/shielding/rod and then putting down a testable, clean bead on something critical, that is where the skill is at and when you might want to hire someone with actual certs, training and experience.
"You could teach a child to do it [welding]"...
Not based on my experience as a child...
If you are talking about "Gas Welding" (aka Oxyacetylene welding) I can agree as I learned to do this in my very early teens (late 1970's) at my Dad's Sheet Metal Fabrication business (at school my teachers couldn't believe how good I was in the Metalwork classes with Oxyacetylene welding).
If you are talking about the other techniques of welding by hand such as Stick (Shielded Metal Arc Welding), TIG (Tungsten Inert Gas Welding) and MIG (Metal Inert Gas Welding) then I have to disagree...
My Dad (who excelled at these techniques) eventually gave up on teaching me Stick and MIG welding after a few years - I couldn't get the hang of it...
My Dad said my (not Oxyacetylene) Welding always looked like Cocky Shit Droppings - and I had to agree :)
My brother "taught himself" welding and attempted to do up his rusty banger on our driveway in front of our and the next-door neighbour's garages. He was banned from using it after said rusty banger was reduced to a burnt-out husk and the paint on the metal garage doors had blistered alarmingly. Parents (and next-door neighbour) were definitely not amused.
Your dad might just have not been the teacher you needed for those techniques. Knowing how to do something well yourself doesn't necessarily translate to being able to convey that skill to someone else. My experience (learning the basics as a 19 year old) was that TIG and oxy were for instance extremely similar. TIG is less likely to blow your melt puddle around, but in terms of puddle control I found them (and they were taught to me) as very very similar.
Surprised no one just went full retard and pulled out the thermite. ;)
I would have thought in the original rather extraordinary case an ad hoc team would been formed which analysed and documented the problem, evaluated the possible solutions, also documented, and having selected presumably the least worst option, prepared a plan for the preparations, execution and clean up which would have been examine by all the parties involved and after feedback amended.
Once the operation was complete a debriefing session (or post-mortem) to record what did happen and unexpected problems that arose and their rectification.
All the documents catalogued and placed in long term records storage along with a mothballed wielder.
The ad hoc team then dispersed.
Such ad hoc teams should be formed under the auspices and direct report of a very senior executive (VP level) to prevent the usual duck shoving.
When years later when the same problem arose this documentation could have been perused by a similar team and the script including checklists followed (hopefully ensuring beforehand the latter day Andy was a competent wielder with an off-site practical test.)
Today's IBM having eradicated it's dinobaby infestation would have some fresh liberal arts graduate turn up to repair your mainframe while pulling out a thermal lance declaiming "this should fix that baby!" Doubtless.
"you might want to hire someone with actual certs, training and experience."
That really depends on the job , if its an undersea pipeline that if it fails will kill a dozen people then yes. If its a quick bzzt with an arc welder to get a couple years more life out of the garden gate hinge self taught Barry from next door will do.
Personally I seem to be getting worse at MIG welding , some combination of me & the welding machine getting older & the metal I'm trying to weld getting thinner (my ageing cars)
> ...procedures for Hot Work processes...
Place where I worked was real uptight about that. Campuses were hundreds of mostly older buildings with leaky roofs, they got tired of fires on the roofs. A contractor who even started hot-work without a pile of paperwork and signoff from multiple offices and the fire department (they had their own!) could be permanently banned from bidding on jobs. Similar for welding and plumbing. In retrospect I dunno why they didn't get on my case for soldering much of the time.
In US English-- 'burning' is melted Lead (batteries but also lead roofs), 'soldering' is Tin/Lead filler (or now semi-similar compositions), 'brazing' is like solder only a copper-base filler (fine bicycles but also traditional on Freon machines), 'welding' is molten iron/steel. 'Hammer-welding' goes way back, the base iron is softened and forced to merge. Most modern welding uses increasingly sophisticated steel alloys as fillers on various base steels. (True Iron is only for historical fanatics, it's all steel now.)
I did a stint as a bowling alley mechanic. Venerable old 82-70's for those that care. I had to explain several times to various managers why a two minute weld on a part would take a day to do as I could not weld it while in situ. It had to removed and welded in the workshop, which was in another site.
Let alone the stray currents and EMF that could damage the computers in adjacent lanes, which I could have removed and moved somewhere safe, all ten of them. There was also the considerable risk of fire. A dialy task was cleaning oily dust from the machines, applying new oil as required and polishing all the slidy parts.
After carefully explaining the risks they'd agree with my assessment.
Not that they has a choice as I'd point-blank refuse to weld in situ. no matter what their opinion was.
One of the women in our property management department put herself through college as a small-engine mechanic. If anyone had a problem with a generator or a forklift she got called before we ran to the service company because even if she couldn't or didn't want to fix it she could do better troubleshooting than anyone on staff and it cut down on the repair times.
In August one year we're doing the annual disaster readiness check, and part of that was looking over all the portable generators we had in case of trouble with our big diesel genset.
One won't start. The IT guy checking them tries spraying starting fluid on the air filter, tries changing the plug, etc. Normally he'd just put in a ticket and assign it to property management like he would an out-of-date fire extinguisher. But not this time. He's a smart guy! He can probably figure it out a lot faster than that old lady can!
It isn't spark (he shocked himself testing it) so it has to be fuel! So he takes apart the carburetor, cleans everything even slightly dirty, and puts it back together.
Not only doesn't it start, it also leaks gasoline. He takes apart a working generator to compare, finds he'd done something backwards, and then reassembled them.
Now neither starts and both leak.
As he's taking apart a third to compare it to the previous two he gets caught because the warehouse reeked so badly you could smell it inside the office.
The woman from property management finally gets called. She walks down, takes a cursory look, and says "You can't start them with a closed choke, and you can't reuse gaskets."
Three dead generators out of nine was a fail, so we re-ran the entire DR check three weeks later after they'd been serviced and Mr. Mechanic had been given walking papers.
You'd think that repairing a working something into a dead something would be clue enough that you might want to pull your hands off and admit you don't know what you're doing... walking papers richly deserved for digging into the third one imho.
Reminds me of the story told to me by a team lead I had decades ago.
He was responsible for repairing helicopters for a large military organisation. And he pointed out to his boss that the biggest delay in getting them out the door was trying to find a pilot with the free time to test them after repair. His solution was that they paid to get him trained up to be able to do the testing and shakedown flights ........ which they did!
Best bit of on-the-job training I've ever heard of!
trying to find a pilot with the free time to test them after repair. His solution was that they paid to get him trained up to be able to do the testing and shakedown flights ........ which they did!
Well, the cook should taste the dish first, and if he's willing to fly it first that should inspire confidence.
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It was one of those "white heat of technology" things in the 1960's. There was coverage in Tomorrow's World from James Twerp et al showing two pieces of metal welded perfectly after a whizz bang cleaned off all that surface stuff and brought the two pieces together. Like things such as fluidized sand reactors, it faded from view although I'm sure they're all very important somewhere.
Meanwhile British industry kept on adding go-faster stripes to everything.
From the vintage, I'm assuming that the printer involved was the IBM 1403 line printer, which had the character set on an endless chain that looked very much like a chain saw blade. It whizzed around at frightening speed with hammers synchronized to hit the passing letter or number at exactly the right time and in exactly the right place. It made an infernal racket. I can't imagine working in a data center where they had dozens of these beasts cranking day and night. Ear protection would be mandatory.
This was back when IBM was remarkably adept at building hardware[1] and it was a true electro-mechanical marvel. IBM had nothing to top it until the laser technology 3800 Printing Subsystem, as it was called, came out in the late 1980s, if memory serves.
One of its features was that when it ran out of paper, it would open itself automatically to allow the operator to load a new box of fan fold paper.
I worked at a US military-operated graduate university for a number of years in the 1970s and, for some reason, we had one of these beasts in the output room where the users could get at it. Every once and a while some unsuspecting student would put their books on to of the machine and have them dumped unceremoniously on the floor to the accompaniment of much swearing on the part of the victim and much laughing by everyone else.
[1] The IBM "golf ball" Selectric is still my favorite typewriter. I wish that modern computer keyboards had the wonderfully positive feel of that keyboard.
Well, darn. I was about to write a very similar comment. We had one of these chain printers at university back in the 1970s, and it was exactly as you described.
Opening the lid was very effective. Even just sitting there not printing, it would scream like a banshee.
I usually describe the chain as resembling a bicycle chain, myself. Two characters per link, as I recall. The letters on the paper were smeared sideways a tiny bit.
Found this page with pictures and everything. Enjoy. https://ibm-1401.info/1403Fonts.html
My very first job was working as a "tape monkey" in a datacentre that had these things, 8 of them in a padded room. The "printer victim" each night was chosen by short straw and the poor sod had to wear ear protectors and was only allowed to be in there for 15-20 mins at a time to deal with paper loads, collect the outputs.
So be careful what you touch.
Really, what was our brave engineer thinking? Even a perfect job leaves the window open for repercussions if anything, even something unrelated, goes wrong in the immediate vicinity. Printer on the fritz? Too bad, buy a new one.
Treat anything client related as radioactive, only touch if ordered to do so, in writing.
bring back my PTSD why dont you...
Of the piece of expensive military kit , all cutting edge electronics..... only thing was the support frame had a broken bracket. "I got this" as I wander off to a workshop to drill 2 holes in a bit of plate to make a temp new bracket........
And by the time I get back, someone has gone "I got this " with the arc welder........
Our electronic guys sure enjoyed that weekend of stripping it down to find the failed parts.
The guy with the arc welder...... we drove 2 nails through his boots then welded them to the crane jib. if the electronic guys had their way he would have been wearing them when we did it....
I'd have to say you don't necessarily need to be a skilled welder to just weld something for repair purposes, however there are concepts you need to know and common sense type knowledge working with such things. So no, some jackass with an arc welder and electrical outlet to plug it into need not necessarily apply.
In any case, it wasn't even the welding itself that was the problem, but the knowledge of fire alarms and consequently, the harm caused by the unnecessary evacuation procedures.
(I used to get a laugh out of "no smoking in the welding shop!" for either reason)
Title says it -- I assumed the arc welder was going to toast the machine (the printer, run through the "data hose" -- I'm sure this had one of those thick cables -- into the machine and put some high voltage in there as well.). Not the ending I expected! Good one!
There's loads of types of welding.
One of them used for welding soft drill shanks to hardened drill bits involves spinning each drill part in opposite directions,then ramming them together and let friction do the job.
Soldering has an oddity, silver soldering which is actually brazing,called silver soldering for no particular reason.
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