|Andrew Johnston||21/01/2020 20:58:15|
5115 forum posts
According to my dictionary braze is from the old French word for burn. I'm not a fan of burnt steak!
|Michael Gilligan||21/01/2020 21:40:27|
14783 forum posts
Looks like Braze might be quite a versatile word: **LINK**
|Nicholas Farr||21/01/2020 23:24:31|
2067 forum posts
Hi, I think it's a shop floor definition thing that spread throughout industry, in that, when you were instructed to braze something up, you knew that you had to use brass filler wires and if it was to be silver soldered, you would choose a wire that you considered right for the job in hand or one that you were instructed to use. Either way you would understand the nature of the actual process required and do the correct preparation and use the correct flux and heating etc.
481 forum posts
It's amazing how technology has moved on. We are talking about soldering & brazing to stick metal parts together. In the car industry they now stick (bond) car chassis to body components using glue. Stronger than welding. I have a fairly new car that is pretty much glued together. The whole body & chassis are made from alloy. Putting out 575 hp through the wheels & it's glued together. Forgot it has lots of plastic too. Not like my 1st Morris minor traveller. R.I.P.
1669 forum posts
Indeed Steviegtr, eventually this technonogy will filter down to home use. Not sure how strong the glue will be in 100 years though
|Nicholas Farr||22/01/2020 08:43:27|
2067 forum posts
Hi, I used glue back in 1987 or there about, to fix four stainless steel patches on the wings of an Avenger to get it through the MOT, although the wings were not in there own right subject to any structural issues, but rusty jagged holes in a position where they would cause additional injury to persons if they were struck by ones car, are.
The photo above shows one of the patches. When I took it for the MOT, the examiner was intrigued by my simple solution to the problem and passed it OK. The next year he told me that Vauxhall were gluing the wings on their new builds.
Maybe this could be low temperature brazing, as there is a small temperature rise during the curing of the glue I used.
3989 forum posts
Wow. It still goes on. So I guess Michael G's answer of "No" is definitive.
Here is what the industry experts at CupAlloy say on their site:
"The brazing process, of which silver soldering is a part, has been used successfully for thousands of years to produce strong leaktight, ductile joints ...
...One definition in British Standards defines brazing as : "a process of joining generally applied to metals in which, during or after heating, molten filler is drawn into or retained in the space between closely adjacent surfaces of the parts to be joined, by capillary attraction"
International Convention declares that brazed joints are made above the melting point of aluminium 610 degC. Below that temperature you are soldering. A brazed joint is identified by the temperature of the filer metal, not by the composition of the rod in the hand."
CupAlloy's full screed and lots of other interesting info on the topic is here **LINK**
But the above definition is, as discussed earlier, contrary to what many who did a machining or toolmaking apprenticeship in the days of yore was told on the shop floor, where "brazing" referred to the use of brass rod and "silver soldering" to the use of a silver-bearing wire filler.
Not sure how, when, where or why the discrepancy over the years. Was it the British, ISO, or SAE Standards organisations getting in on the act and coming up with a standard definition in later years?
Edited By Hopper on 22/01/2020 09:04:53
684 forum posts
Well I wrote a bit about soldering, brazing and welding for my website. Not sure that it adds anything much to the discussion but there are pictures and links!
|Michael Gilligan||22/01/2020 09:32:51|
14783 forum posts
Thanks for the clear statements, Hopper
It appears that the ‘decree’ came from the American Welding Society [please see my link, posted yesterday], and that it has subsequently been adopted worldwide.
The fact that I personally find the definition counter-intuitive is of no consequence.
A fuller answer to the opening question would be :
No ... because what was previously known as ‘Silver Soldering’ is now defined as Brazing.
|Martin Kyte||22/01/2020 09:33:14|
1583 forum posts
This one is going to run and run.
Taxonomy is very dependent (maybe that should be totally dependent) on the parameters you use to form similarities and distinctions when grouping stuff in any kind of structured relationship. In order to bring some order to the vast diversity of life early classifiers notably Carl Linnaeus quite reasonably chose easily identifiable characteristics to assemble his groupings with more specific characteristics used to subdifine larger related groups with common attributes. Largely this methodology has stood the test of time although modern genetics has led to a good deal of shuffling around in terms of close relations.
Along side all this has always been common names which by their nature are specific to the 'thing' and sometimes very 'local' in their usage.
Spade is a common name and you need to know what it refers to to make any sense of it, personally operated earthmoving artifact is more descriptive and will universally convey more information but no one would see it as being particularly convenient to use.
In similar ways engineering terms can be common usage or more technically precise. As a classification all forms of 'welding' should really be fusion bonding and all forms of 'soldering' should be thermally induced capilliary bonding by sub melting point filler material (or some such) and then further subclassified in terms of the filler material. So to fully classify this particular subset of jointing we would need a binomial classification.
Practically speaking no-one is going to bother with all this and everyone will carry on with the common name for what they are doing. You can always ask for a description if you don't know what they are talking about.
Edited By Martin Kyte on 22/01/2020 09:33:28
Edited By Martin Kyte on 22/01/2020 09:34:44
Edited By Martin Kyte on 22/01/2020 09:35:00
|Russell Eberhardt||22/01/2020 09:39:04|
2534 forum posts
Even more confusing, current French uses "Soudage" for soft soldering, silver soldering, and welding. The French term "brazage" refers to using a brass (laiton) filler.
|Clive India||22/01/2020 09:44:53|
207 forum posts
Nice one. I agree, providing the correct glue is used for the job and the application notes are followed. No good just trying anything - research the most suitable, they did all that with your car!
|Mike Poole||22/01/2020 09:50:13|
2331 forum posts
This can of worms has existed for many years and just to add to the confusion there are various definitions. As long as you are clear on what each process requires and what is best suited to a given task then call it what you prefer. My personal preference is silver soldering which I use for the process that uses a silver based filler rod and brazing for a brass based filler, bronze welding is another process but unless you have an oxy fuel torch this will not be an option. Brazing was possible with the old town gas and a blower but I get the impression that a propane only torch is on its limit for brazing. As silver based rods are expensive then if you have enough heat brass brazing is an economical choice for steel but for odd jobs silver soldering may work well. Sticking to the rules is vital to success in silver soldering, if you deviate then trouble is likely but if you adhere then success is likely.
Edited By Mike Poole on 22/01/2020 09:52:28
|Nicholas Farr||22/01/2020 10:18:43|
2067 forum posts
Hi Mike, when I was at secondary school we used a brazing torch that used town gas and an air blower in metalwork classes. I doubt many youngsters today will ever get the experience of them now. We never were given the opportunity to do silver soldering though, maybe because of the cost, and therefore the teacher did any silver soldering that needed to be done on our work.
|Michael Gilligan||22/01/2020 10:51:50|
14783 forum posts
|131 forum posts|
I stand properly corrected by Bill Davies, it is book no 9 . My reference to no 6 is either a typo on my part or more likely my usual problem with FFS ( fat finger syndrome! )
Despite all of that I still recommend it as a worthwhile read.
481 forum posts
We had one in the Metalwork shop at our school too. I was 14 at the time & the teacher let me bring a cut down Velocette pushrod tube & a Villiers 2T inlet manifold in to class & braze them together, so I could fit an Amel monobloc carburettor to my Villiers engine. The teacher was amazed how I could braze. Weird when people ask you things like how do you know how to do that. You cannot answer. Maybe you see things & absorb them.
|Mike Poole||22/01/2020 13:02:21|
2331 forum posts
Looks like a few of us were introduced to brazing with town gas and blower, the conversion to natural gas never seemed as good. Working in a factory oxy acetylene was readily available and a good mate was a skilled welder, we made the skilled distinction as in a car factory many people were trained to do specific welding tasks and they were damn good at the specific task but the skilled welder was taught all welding disciplines and could weld any material. They also understood the metallurgy side of the job so they were a very different animal to a production welder. Some of the production guys ran fearsome settings on their machines, everything up to 11.
|Gerard O'Toole||22/01/2020 13:04:19|
|36 forum posts|
It probably depends on whose word definition you believe
“When I use a word,’ Humpty Dumpty said in rather a scornful tone, ‘it means just what I choose it to mean — neither more nor less.’
’The question is,’ said Alice, ‘whether you can make words mean so many different things.’
|Anthony Knights||22/01/2020 17:57:12|
|312 forum posts|
I cannot believe this subject has run to three pages. Welding involves melting the adjacent parts of the parts to be joined and when they cool they are attached. I am rubbish at welding.
Soldering, be it Tin/ lead alloy, alloy containing silver or brass all join metals by alloying with them at a temperature below the melting point of the metals you are joining together. The only difference between the various processes is the temperature at which this is done and the soldering rod used. Done this with soft solder and silver solder. Not tried brass as I have had no reason to do so.
Please login to post a reply.
Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!
You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.
Click THIS LINK for full contact details.
For subscription issues please see THIS LINK.