# Silver soldering/Brazing technique



## chucketn (Dec 7, 2012)

I have a noob question on Silversoldering/brazing. I have only silver soldered 1 part in my life. Ihave a part that press fits together with finger pressure. It's ashaft for a crank, and the other part is the flange for the crankbearing. Is this type of fit 'loose' enough  for silver solder towick/wet between the parts?

Should I flux the mating surface ofboth parts before pressing together?




Chuck


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## GWRdriver (Dec 7, 2012)

Hi Chuck,
These parts really do need some clearance, but not much.   I would suggest making the finger-press fit into a slip-fit by relieving a bit on the shaft, but NOT so much that it allows a visible wobble of the crank or flange.   Then, I would create a couple of pathways, channels, to allow solder to flow into that shaft seat.   I would use a triangle or wedge needle file to put 2 or 3 shallow nicks in the bore IDs to allow the solder flow in.   If you are up against a shoulder on the shaft, turn or file a clearance angle on the shoulder to allow solder to flow to the seat.  Use plenty of flux and as it liquifies it will find its way in.


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## goldstar31 (Dec 7, 2012)

If you are wanting to do a silver soldering task after only ONE go prior to tackling what could have been hours and days of work, I would caution you to think again.

What you should be doing is learning how to silver solder and not asking how to silver solder a crankshaft- in x number of bits.

I would advise you to perhaps follow the advice which others may give but -- not on your work. Practice on something until you can 'stick the tail back on the donkey- if given the right flux'


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## gus (Dec 7, 2012)

goldstar31 said:


> If you are wanting to do a silver soldering task after only ONE go prior to tackling what could have been hours and days of work, I would caution you to think again.
> 
> What you should be doing is learning how to silver solder and not asking how to silver solder a crankshaft- in x number of bits.
> 
> I would advise you to perhaps follow the advice which others may give but -- not on your work. Practice on something until you can 'stick the tail back on the donkey- if given the right flux'



You are right. I messed up two good parts before getting best results on a third piece.Silver Brazing can be very tricky.Brazing temperature got to be right.Tubal Cain has written a book on same subject--------Soldering and Brazing.
Brazing torches must have the power.Rod selection critical. 

Gus.


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## sunworksco (Dec 7, 2012)

Use the correct solder, flux and temperature. The solder will bead up like water droplets.


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## Jasonb (Dec 8, 2012)

sunworksco said:


> Use the correct solder, flux and temperature. The solder will bead up like water droplets.


 
Thats exactly the opposite to what you want and is usually the sign of a joint that has not got hot enough.

The solder should "wet" the parts and flow through the joint and form a small fillet in the internal corners though ona  crankshafts it is better to have a small countersink for the fillet to form in so the job can be cleaned up without machining away the fillets. You can just see the ring of solder in teh CSK on this crank where it has been filed smooth on the inside


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## goldstar31 (Dec 8, 2012)

Unfortunately, the answers are coming in from various forums(?) and I am dotting about between them and losing concentration( and interest)

I have said 'practice, practice' and others have said 'wicking' and I would agree. I would, however, question achievement of the 'little globules' being wrong. If one uses silver  solder paste, there will be 'little molten globules' appearing in the flux and dross and the latter will have to be removed to 'wet' the joint.

As far as the intended joint(s) are concerned, I would agree about 
1. the necessary clearance between surfaces to be joined
2. I would have a little recess cut around the female part(ouch)
3. Then I would place a ring of silver solder in the recess which has already been prepared with wet flux. This wet flux is important as the torch will blow powder away.
4. The flux will turn glassy with the heat and hold the ring of solder in place.
5. As a belt and braces exercise, the fluxed extra silver solder rod should be in place to add an extra  dab of solder to complete the joint.

Probably the biggest mistake in welding, brazing and welding is 'fear' and the reluctance to get in to see exactly what is happening.


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## Jasonb (Dec 8, 2012)

If placing bits of solder onto the joint then applying heat you can see the solder will melt and form into small balls which is what Giovanni describes. It is only when the whole job is hot enough that these balls will flash around the joint which is a sign that all has been got upto the correct temp.

If your joint has lumpy solder and blobs sitting on teh surface then you really have not got the metal hot enough.

This is the look you should be aiming for, a nice line of solder along the whole joint where it has wetted the whole thing






And another where it has wetted both surfaces and formed a small fillet


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## goldstar31 (Dec 8, 2012)

'If placing bits of solder onto the joint '

I said 'a ring' of solder. this is a 'male/female' joining- and my words were to that problem- and no other. 

Pedantic, maybe but so it should be. 

regards

N


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## MuellerNick (Dec 8, 2012)

For a plug/hole job, a fit that allows the parts to slip together just by gravity is best. File some flats around the circumference that helps the silver solder to be sucked into the narrow gap.
One thing that is often done wrong: Too slow heating up. The longer it takes, the thicker the oxide layer the flux has to break up. If you apply the flux before heating up, you only have about 30 seconds before the flux no longer works.

A steel needle helps to spread the silver solder in chamfers.

NEVER direct the flame to where you want to solder, but get the heat at the joint indirectly.


Nick


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## Jasonb (Dec 8, 2012)

goldstar31 said:


> 'If placing bits of solder onto the joint '
> 
> I said 'a ring' of solder. this is a 'male/female' joining- and my words were to that problem- and no other.
> 
> ...


 
It may have come over wrongly. I was not suggesting you were "placing bits of solder" rather than rings, I was refering to the general practice of placing pallions but the OP may not have known what this meant so "bits" was a better description" With this method the pieces of solder do tend to melt and form what could be described as "droplets of water" before the whole job gets to the right temp for the solder to flow.

Personally I tend to feed in the stick 95% of the time but will use rings or pallions if the job requires it.

J


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## goldstar31 (Dec 8, 2012)

Jasonb said:


> Personally I tend to feed in the stick 95% of the time but will use rings or pallions if the job requires it.
> 
> J


 
Shhhhhhh! So do I but after all, we have been doing things a loooooooooooooong time.
To be honest I wouldn't have even bothered to to get the gas out. Probably, stick a bit of carbon from a zinc battery on one electrode of an arc welder and whey heigh. Or a spot from the mig/mag in the right place. 

But this wasn't the question :hDe:


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## gus (Dec 8, 2012)

Hi Jason.

Crankshaft very well done and silver brazes. For I am still shying away from same jobs as my brazing equipment is not up to mark. Have seen the professional aircon plumbers silver brazed copper pipes and they made so easy.


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## Jasonb (Dec 8, 2012)

Thats a different mixture of metals that they use in the solder for air con pipes and not really suitable for our uses.


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## goldstar31 (Dec 8, 2012)

Gus,
  it may not translate between our two Identical languages but solder in the UK is leadbased and silver solder is obviously silver and needs a higher heat.
Even lead based is a bit of a misnomer because for plumbing we- cannot use lead anymore.
You can chew off the heads of lead soldiers but you can't drink what comes out of the tap.

You can- if you lead a blameless life- live to 82( so far) with all sorts of lead paints and whatever--------------------------and it doesn't affect me-me- me- me!
So stick with a high silver solder which melts fairly easily until you a experienced, have read up the topic, got a better heat source.

Having said all that- good show!

Norman


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## gus (Dec 8, 2012)

Jasonb said:


> Thats a different mixture of metals that they use in the solder for air con pipes and not really suitable for our uses.



You are right. Please advise silver content for Steel. I am not very knowledgeable on Silver rods. Buy from neigbourhood weld shops but would ask for best rods for the job. Like brass to steel. Steel to steel. etc.
Plan to brush up on Silver brazing.


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## goldstar31 (Dec 8, 2012)

Gus,
  For the time being go for a high content silver solder-- and with nerves of steel, use   a strong spanner to open your pocket book.

You may need a hammer to smash your piggy bank as well, but it makes life so much easier.

Somewhat whimsically but right

Norman


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## jasonh (Dec 8, 2012)

MuellerNick said:


> One thing that is often done wrong: Too slow heating up. The longer it takes, the thicker the oxide layer the flux has to break up. If you apply the flux before heating up, you only have about 30 seconds before the flux no longer works.
> Nick



Okay Nick - I'll bite.

The way I do it (and have seen it done) is to make a paste of the flux, apply it to the joint and then have at it with the torch and the silver braze.

And I would agree- if you lay too much heat into the joint it a) oxidizes the metal and b) appears to destroy/oxidize the flux. It's a delicate art to get it right.

So - applying the flux *after* the preheat and slightly before the metal is probably the way to go. The question is - how are you getting the flux onto the joint?

I don't see how you could do it in the manner of rod brazing (ie on the rod) since you normally snip off as smaller piece of silver braze as will do the job.

Also - I've been using oxy-acetylene as my heat source. Certain authorities (E.g. Kozo Hiraoka) say that propane is the way to go. Any thought on that? 

Straight propane seems to be a bit cold. Should I get a oxy-propane torch for my silver brazing work?


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## rdhem2 (Dec 8, 2012)

I don't know if this technique fits here but when possible I like to do the following.  Use a spring loaded clamp to hold the part in place.  Prior to this flux and put a very light coat of silver solder on the two pieces to be joined.  File the solder as necessary to reassemble the parts.  Reflux the joint, clamp in place. heat the _surrounding_ area quickly with a torch until the bright flow of solder is seen at the joint.  Don't DADDLE, you are done.  Allow to cool.  When the solder remelts the spring pressure closes the joint.  This has worked well for me and usually requires little to no clean up of the joint and little to no oxidation as the heat is not allowed to get that high or dwell that long.  Works great on things like soldering ramps and pistol sights.  In lead soldering I've heard it refered to as sweating but not when using silver.  Not a welder, just a sticker together'er.


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## Jasonb (Dec 8, 2012)

Gus, the solder you have seen the aircon guys using is not a lead bearing solder with a low melting point it is a low silver content solder that has a similar melting point to the type of Silver solder we are talking about. Thes eaircon solders have 5-6% silver content and would in the US be something like the Harris Safety-silv 5

For boiler work and fabrications you want to be looking for a solder with at least 45% silver, in the US this would be Harris Safety-silv45, in the UK Easyflow No2. If you prefer the cadmium free or like us have to now use cad free then the silver content wil go up to compensate to around 55% this would be Silverflow or 455 and the international ref is IS0 17672 Ag 155.

Regarding fluxing. This is best done by mixing to a paste, apply to all surfaces you want the solder to stick to and then start heating, you don't need to preheat or apply further flux in most cases but if you do then slightly heat the end of the rod, dip it in the powder and this will coat the rod in flux which can then be fed into the joint.

I would say propane with a suitable burner is they way to go, the risk with a gas/oxy mix is that the flame is very concentrated so you end up just melting the solder onto the surface and don't get heat into all the joint. Oxy-gas can be handy on a big job where the whole thing is heated to just below melting point with a propane burner and then the oxy-gas used to work around the job.

Straight propane will melt the parts being joined let alone the solder when working with brass and copper so if definately not too cold. Its all about having a suitable size burner to get sufficient BTUs (watts) of heat not the temp the gas or gas mixture burns at.

J

EDIT

Russ your method applies to the low melting point lead bearing plumbers type solder which is silver in colour but not the silver solder we are refering to and is known as sweating the parts together and certaily works when that type of joint is needed.


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## sunworksco (Dec 8, 2012)

The best gas combination is propane and oxygen. These gases leave less carbon residue and give the best temperature range. It is also less expensive to purchase. Yes. You can use only propane but it is a PITA.
Also, if you have access to a kiln, this is a very clean and efficient way to silver solder. Just clean, flux and place the solder on the joints.


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## MuellerNick (Dec 8, 2012)

> So - applying the flux after the preheat and slightly before the metal is probably the way to go. The question is - how are you getting the flux onto the joint?



With the silver solder rod. Or a screwdriver or whatever is near.



> I don't see how you could do it in the manner of rod brazing (ie on the rod) since you normally snip off as smaller piece of silver braze as will do the job.



I almost never snip off the braze. I just use it off the rod. This implies that the rod melts when contacting the work, I never melt it with the flame because that makes the blobs some here do talk about.
If needed, you can chase the melt with the flame or with a steel pin to where it didn't want to go.



> Also - I've been using oxy-acetylene as my heat source. Certain authorities (E.g. Kozo Hiraoka) say that propane is the way to go. Any thought on that?


Well, if someone tells you that you need propane, he is ruling himself out as authority. At least in my eyes. I do have 4 different burners, each one is good for some job, none is good for all jobs. O/A for big pieces, 2 propane for smaller ones and a micro propane/oxygen for small jobs.
With O/A, a rose butt is advisable. If you don't have one, use a soft flame and only the blue cone of the flame to heat up. Takes some practice.

Nick


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## Jasonb (Dec 8, 2012)

There is another Silver soldering thread on another forum about type of torch and gas to use and this is the reply from one of the trade solder suppliers that has 35 years in the industry working for both Johnson Matthey and running his own company, I'm sure he won't mind me posting it here

"Beginners should steer clear of oxy-gas systems. The heat is too concentrated and you may find it difficult to heat the joint properly to achieve the necessary capillary attraction required to attain the complete penetration of the alloy and strong leak free joints.

    Go for propane, it is cheap, effective, efficient and versatile. Get a variable 1 - 4 bar regulator. This will set  you up to produce between 84 and 0.25 kw of heat from your burners. The best in the range is undoubtedly Sievert."


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## sunworksco (Dec 8, 2012)

I have been a pipe fitter since 1969 and have used propane, Mapp gas, acetylene, acetylene/oxygen, oxygen and oxygen/propane and have soldered copper tubing over 6" in diameter. Oxygen/propane is by far the fastest and most efficient for my silver soldering. I not only use a full sized torch setup but also use the French made MiniFlam. It has the tiniest flame for jewelry. Over the years I have soldered over 100,000 joints. The best thing to do is start learning to silver solder with the less expensive Silfos solder and then graduate to the more expensive higher content solder after that. Silfos solder is ok as long as it is not used for a boiler.
I use a titanium stick for moving solder since solder will not stick to it.


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## gus (Dec 9, 2012)

Hi Jason

Will stock some silver rods of 45% silver. IS this rod overdone for copper boliers?

Gus


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## chucketn (Dec 9, 2012)

I want to thank all who have commentedand offered advise on the techniques of silver soldering/brazing. Alot of good info to think about and apply.

A little background on me. I havesoldered for electronics for many years. I actually taught highreliability soldering for the USAF for many years. I have also donesome plumbing soldering over the years using propane and mapp gas,even an old kerosene blowlamp. I have only silver soldered/brazedonce, and can't find that part now! So, I am familiar with theprocess and what solder flow and wicking look like.

I have my Dad's Proto torch set,regulator and acetylene tank that I intend to use for silversoldering/brazing. It needs a new hose, as the original is lookingdry rotted and I don't trust it. I'm looking for firebrick to make ahearth, and have found a local supplier for the solder and flux, anda replacement hose.

I have uploaded a photo of the parts Ineed to silver solder/braze.

http://i571.photobucket.com/albums/ss157/chucketn/DSCF1344.jpg

The part, shown assembled at the top,and the 3 components at the bottom, is a connecting rod for a modelsteam engine. The clevis on the right end does not get soldered. Theflat part on the left gets soldered to the end of the rod in theposition shown at the top. The rod part is run of the mill 3/16CRS rod, not modified other than faced in the lathe and threaded forthe clevis. The flat piece is 1/16 crs plate, drilled and tapped2-56 on the outaide holes and drilled 3/16 in the center.

As made, the flat piece is a lightpress fit on the rod. I used a ball pien to tap the rod into the flatpiece on the anvil part of my bench vise to get a flush fit. I cantwist and pull the flat piece off the rod with my fingers. I used a3/16 drill to make the mating hole. If I use a #12 drill the flatpart is  loose on the rod.

Hope this clears up your questions andgives you a mental picture of what I'm trying to do.

Chuck


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## gus (Dec 9, 2012)

We have high pressure compresssor C.I. outer head and a steel valve body insert to silver braze.Despite going the highest silver content,reject rate due to porosity was high---------50%.
This was in China 2004 and Gus was the so-called Manufacturing Consultant. Straight off I advised Gus knows nothing on Silver brazing.I recalled Ingersoll-Rand,India Plant used electric furnace to batch silver braze same parts and reject rate was constantly low but parts must be very well degreased and surgically clean.Advised them to use electric furnace. A week later a "thank you" note came.Problem solved!!!! Ha Ha .Gus knows nothing on Silver Brazing!!!!


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## GWRdriver (Dec 9, 2012)

Chuck,
Hmm . . . smallish and delicate assemblies, so by all means do one of these . . . I'm going to assume you will end up with some wire solder, possibly 1/16", or larger.  Take a short piece of wire and pound it flat on a flat surface (anvil, railroad rail, steel block, etc, but NOT a machine table) and make as much of a ribbon of it as you can get it.  It's hard stuff and is going to take some pounding to thin it out.  Once you have a tape or foil snip a narrow slice of the tape use this as you would a stick of solder.  The reason for this is, it isn't going to take much solder to make these joints, in fact a WEENSY bit of solder is going to do it and 1/16" or even 1/32" wire is going to leave you with more solder around your joints than you want.

The other option will be to file some wire into a few grains of solder dust, mix it well with a dab of flux, and apply.  The point is, it isn't going to take much to make these joints.


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## Jasonb (Dec 10, 2012)

Looking at your parts here are a few thoughts

You definately want a slacker fit, a hammered in part is much too tight so spend some time working out how you will hold them in position, ideally the flat part should have been left over thickness so the finished fabrication can be held in the lathe to skim the face true to the rod, you will still have to do this but the less you have to take off the better.

As GWR says using thinned rod either fed in or made into a ring will save you getting too much on the job. One note on hammering it flat do it on a clean surface with a clean hammer, don't want to embed dirt into the solder.

Apply the heat to the round rod as that is where the bulk of the metal is.



J


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## MuellerNick (Dec 10, 2012)

> Theflat part on the left gets soldered to the end of the rod in theposition shown at the top.



I would TIG that. 

You made a design error here. The rod should have a recess as long as the plate is thick. So you have a definite reference where the part goes to. Of course, the plate needs a smaller bore then.
A propane burner is the right tool here.
I'd file two flats on the rod's end (0.1 mm), a slight chamfer on the plate and stick the parts together. I wouldn't hammer silver solder plates as working from the stick works perfect. As long as you don't heat the rod with the flame. That is a common error that leads to those "tricks" with filing or hammering the rod.

Working with rings and ribbons is very common, but almost always only when furnace brazing.


Nick


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## chucketn (Dec 11, 2012)

During my research for my silver soldering project, I came across the .pdf linked below. It has good info including pictures of a reducing flame. I had run across several references to a reducing flame but this is the first illustration I've found.

www.richard-whitehouse.co.uk/*Soldering*%20notes.pdf


Chuck

edited to correct spelling and spacing


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## GWRdriver (Dec 11, 2012)

Chuck,
The URL doesn't work because it also contains a URL for HMEM and it takes us (or at least me) back to the HMEM first page.  Simply plug in only "www.richard-whitehouse.co.uk/Soldering%20notes.pdf" and it will come up.  Otherwise that is about as clear and thorough an instruction for hobbyists as I've seen.


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## Ken I (Dec 11, 2012)

You can heat the part and let the heat spread to where it is needed but I would disgree with not applying the flame directly - however use a carburising / reduction flame (rich) and never remove the flame once applied until the job is complete - otherwise you allow air to your hot part and scale forms.

Use a firebrick nest to keep the heat and the burned gasses in - to keep the O2 out - and to help get to temperature as quickly as possible.

Use preformed rings of silver solder wire or foil (pallions) using a rod only as an emergency standby filler - there isn't time to try poking it in with the rod - this problem becomes more and more evident on larger / more complex joints. 

As suggested in prior posts - practice on something of low value / prior effort.

Ken


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## chucketn (Dec 11, 2012)

Harry, it works for me. I click on the link in my post and the pdf opens.

Ken, thanks for the input, added to my notes.

Chuck


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## rdhem2 (Dec 11, 2012)

Ken;
Thank you very much, well said.  I am not sure exactly what you said.  It may have been how you said it.  But all the bells, whistles and lights just came on.  I have talked with so many guys about this subject and I have gotton answers as wide as the Montana sky.  But you nailed it, I think it was the remark about jacking around with the rod.  Also your remarks about keeping the 02 out and co2 in make perfect sense.
Thanks again!!!!!!!!!!!!!!!!!


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## goldstar31 (Dec 12, 2012)

I think that you should take the advice of my wife ( who was no mean hand ) and think seriously about preventing silver soldering from running about 'unchecked' She used nothing more involved than a HB pencil around the proposed joints.
As for possible oxidisation, the old recipe was a paste made with ordinary blackboard chalk but there are now proprietory compounds- which I have never tried.


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## Jasonb (Dec 12, 2012)

Tipex type correction fluid is what I use, the solvent based one.

Chuck see my comment on MEM regarding the Stay-brite solder you have bought not being brazing.


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## Wagon173 (Dec 12, 2012)

Not to hijack the thread, but as I was reading this I was thinking to myself that I had been quite good at oxy acetylene welding in school and have kept up with it to a degree since I've been out.  I know in a few weeks, I'm going to come to a similar point where I need to solder something.  Would it be possible to use one of the very small jewlers torches and skip soldering all together?  Seems like it would be a whole lot cheaper to buy some sort of steel or aluminum wire instead of 50 bucks on an ounce of high content silver solder.  Keep in mind the extent of my soldering experience has been with fixing wiring harnesses in trucks.  I was looking at one torch that says it's capable of welding materiel as thin as .001"  Obviously that weld would be very weak, but if you could adjust it to get decent penetration, do these small cranks and such warp even with a small weld?


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## gus (Dec 12, 2012)

Ken I said:


> You can heat the part and let the heat spread to where it is needed but I would disgree with not applying the flame directly - however use a carburising / reduction flame (rich) and never remove the flame once applied until the job is complete - otherwise you allow air to your hot part and scale forms.
> 
> Use a firebrick nest to keep the heat and the burned gasses in - to keep the O2 out - and to help get to temperature as quickly as possible.
> 
> ...



Hi Ken.


I place preformed silver solder rings with a wee bitty flux on the copper boiler sockets. Found this to be best shot instead of poking around with rods.At 69 my hands are not that steady. For copper boiler end caps, I place 1/4 circle formed rings. Then clean up ,turn over and braze the other side. Results been good though I get some over runs. I use Mapp Gas. They now have a three burner torches. Have seen air-con tradesmen using it. They gave me some good tips.Come 2013 will dig out and complete a Colonial-Type Boiler kit bought ages ago. Will buy fire bricks to form up a make do brazing hearth.
Will post if it looks good. Need this bigger boiler to power some bigger slide valve engines.

Gus.


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## gus (Dec 14, 2012)

gus said:


> You are right. I messed up two good parts before getting best results on a third piece.Silver Brazing can be very tricky.Brazing temperature got to be right.Tubal Cain has written a book on same subject--------Soldering and Brazing.
> Brazing torches must have the power.Rod selection critical.
> 
> Gus.



Hi Goldstar  Hi JasonB

Bought an air cleaning gun to match up with the China 1hp close couple compressor which cost me US$96.I could buy same for Rmb300 orUS$50 in China.
The Air Gun fitting had to be re-engineered to fit 1/4" hose with 1/4" hose barb.
Took the gurus seriously and used 40% silver rods. Heated the part to dull red heat and avoiding the sliver ring that I put into barb. At red heat and beyond,the silver solder did run beautifully.Mapp gas used.
Gus is very much a green Silver Brazer.Please view attached and tell me if there are any defects or improvement required.
Higher silver content is hard to buy.
Looking forward to expand the scope of my present machineshop activity with air compressor.


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## goldstar31 (Dec 14, 2012)

It is difficult to tell you- precisely. It would have helped if you had 'pickled' your work to clean up.
Having said that, if you are happy that things are secure, strong enough and gas tight that is fine. Obviously, you will become more skilled and neater as you progress. You have managed- so GOOD SHOW-Well Done.


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## robcas631 (Dec 14, 2012)

If one were try use silver solder, would their be a high temperature flux needed as well.


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## goldstar31 (Dec 14, 2012)

Silver solder( and I mean silver solder) requires a borax based  flux. Things like resin, tallow. spirits of salts, baker's fluid are only suitable for lead solders.


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## chucketn (Dec 14, 2012)

I purchased a container of Roach Powder(Boric Acid) for a couple bucks. Will be back in business today.

Chuck


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## goldstar31 (Dec 14, 2012)

Question???? Are you intending to use silver solder- and I do mean silver solder.

If you are using soft or hard solder, you are simply asking for more troubles by using boric acid.

See my earlier remarks above.


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## Jasonb (Dec 14, 2012)

Chuck as I said elsewhere that Stay-brite solder you have is not suitable for borax based flux, it came with a zinc chloride flux so you need to use that or a rosin one.

The Stay-silv is not a hard solder/braze but a high temp (400degC) soft solder that does have a couple of % silver content. Its is not classes as a silver solder/braze until the temps get to about 620deg C. If buying Harris products you want Safety-silv or at a pinch for non boiler work Stay-silv

The solder will melt before the borak and you will just end up overheating the solder and it won't stick to the metal

J


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## gus (Dec 14, 2012)

Hi Goldstar,
Both mating parts just came off from lathe and hence mating faces clean.So Skipped the pickling.
With copper boilers and end caps,I would use pickle bath. Pickling compound bought from HandsTokyu,Tokyo,Japan. One word of advice.Do not spend too much time in the DIY Hardware floor,I walked out hundreds of $$$ poorer. Going there again this Chinese New Year,mid Feb. 2013 with new year resolution-------Thou shall stick to the "buy plan" and $$$$ limit.
Made in China hand tools are of very high quality in this DIY Complex. Cost a wee bit more than buy in Singapore/Australia.The Made in Japan tools cost a bomb.
Flux. I bought USA "Ultra Flux" specifically for Silver Brazing.Used " their Silvaloy" Silver Solder Rods.
Your expertise is sought on this brand of flux and silver brazing rods. Thanks for sharing Silver Soldering expertise.
Pouring "Dogs & Cats" so not fishing this weekend. Save some $$$$ on diesel fuel.

Gus


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## Jasonb (Dec 15, 2012)

Thats the right flux and solder gus, joint looks OK from what I can see of it.


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## goldstar31 (Dec 15, 2012)

Hi Gus, 
            As Jason says- 'OK'
And with thoughts of Monday the 18th February, I, too, will be celebrating yet another Chinese New Year but in Oriental Lodge no 9371 here in Newcastle. I keep getting more invitations to HongKong but we are getting old.

Meantime, my Christmas Greetings to one and all, 'Slange Var' for the Scottish Hogmanay.

Enjoy, it's only metal

Norman


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## gus (Dec 15, 2012)

Jasonb said:


> Thats the right flux and solder gus, joint looks OK from what I can see of it.



Thank you.  Guru Jason.
At red heat ,the silver rod melted and flow by itself.

About to finish up the Quick Change Tool Post.

Latest.
The hose barb too small and the hose clip too big. Have to machine anther bigger hose barb. 


Gus


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## goldstar31 (Dec 15, 2012)

Why?

Simply split a bit of hose to go over your hose- and put your jubilee clip over that-- then tighten up.


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## chucketn (Dec 15, 2012)

Jasonb said:


> Chuck as I said elsewhere that Stay-brite solder you have is not suitable for borax based flux, it came with a zinc chloride flux so you need to use that or a rosin one.
> 
> The Stay-silv is not a hard solder/braze but a high temp (400degC) soft solder that does have a couple of % silver content. Its is not classes as a silver solder/braze until the temps get to about 620deg C. If buying Harris products you want Safety-silv or at a pinch for non boiler work Stay-silv
> 
> ...


 
So, Jason, as I understand you're saying that I can solder mild steel with the Sta-Brite or Sta-Silv solder I have using the same Kester rosin flux I use with electronics 63/37lead/tin solder? Just need a tourch (propane/Mapp/Acet&air)to get enough heat?

Chuck


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## rdhem2 (Dec 15, 2012)

Shooting buddy of mine was employed at the Bremerton Naval Shipyard.  His job was sweating pipe joints with silver solder on nuclear submarines.  I think I could say he was qualified.  Gary gave me two of his old torches, both shop made and resemble baby rosebuds.  His biggest complaint was getting in all the tight places, using mirrors etc.  Gas was oxy/acet.  His point was you want volumous heat not a directed pencil point of heat.  Heat the part not just a spot he said.  Sounded good to me and works if I do my part.  The welding is the fast fun part.  The assembly and preparation is the important part for success.  Those little 3/16", 90deg rosebuds work like a champ.  Fast and controlable.


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## Jasonb (Dec 15, 2012)

chucketn said:


> So, Jason, as I understand you're saying that I can solder mild steel with the Sta-Brite or Sta-Silv solder I have using the same Kester rosin flux I use with electronics 63/37lead/tin solder? Just need a tourch (propane/Mapp/Acet&air)to get enough heat?
> 
> Chuck


 
No the tin based Sta-brite can use the zinc chloride or a rosin based flux. As this is not a brazing solder. Though I have no experience with your Kestor flux, best check with harris

The Sta-silv needs a borax based flux as it is a brazing rod


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## gus (Dec 26, 2012)

gus said:


> You are right. I messed up two good parts before getting best results on a third piece.Silver Brazing can be very tricky.Brazing temperature got to be right.Tubal Cain has written a book on same subject--------Soldering and Brazing.
> Brazing torches must have the power.Rod selection critical.
> 
> Gus.



Hi Big Bro Goldstar,

Its Christmas .So Gus bought a "South Korean"Double Barrel Torch for double
silver brazing power. Did not cost a bomb.For now I have nothing to silver braze.Will also have to use up two existing Mapp Gas before I can try out new torch. Plan to build a 2" OD boller. Hopefully I get sufficient heat to braze 40% Silver Rods.


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## goldstar31 (Dec 27, 2012)

gus said:


> Hi Big Bro Goldstar,
> 
> Its Christmas .So Gus bought a "South Korean"Double Barrel Torch for double
> silver brazing power. Did not cost a bomb.For now I have nothing to silver braze.Will also have to use up two existing Mapp Gas before I can try out new torch. Plan to build a 2" OD boller. Hopefully I get sufficient heat to braze 40% Silver Rods.


 
Hi Gus
            Good ole Santa. I hope that things are going to get really hot for you-- if you know what I mean?

Santa brought me a rather nice Airfix Spitfire mug to replace my nearly worn out R.J.Mitchell- its designer, one.  May not seem much but I once lived with Spitfires and things.

So wishing you- and the rest of the forum- a healthy and very happy New Year.

Norman


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## gus (Dec 27, 2012)

goldstar31 said:


> Hi Gus
> Good ole Santa. I hope that things are going to get really hot for you-- if you know what I mean?
> 
> Santa brought me a rather nice Airfix Spitfire mug to replace my nearly worn out R.J.Mitchell- its designer, one.  May not seem much but I once lived with Spitfires and things.
> ...



Hi Big Bro,
My 89 year young Aussie Boss was trained to fly Spitfires in Australia during WW ll But soon after he got his Wings the war was over. He has sweet memories flying Spitfires.Just visited him October 2012 and he bought me lunch in Bandanoon a Scottish villiage NW of Sydney.
Was expensive lunch for me as I had to fly over from Singapore and drive to his house--------"Cowan Brae". Boss took me off the street and gave me a job which I worked for 32 years. Good boss taught me all he knew about small---------big Ingersoll-Rand Air Compressors


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