I'm a brazing failure

[ytuyuty]

Okay, I'll admit it. I can't braze anything. And I don't know what I'm doing wrong. In the videos, it looks so easy. Clean, flux, heat, and the joint just sucks up the solder. Done!

 

I'm trying to braze C260 cartridge brass to itself with silver solder.

I clean the two surface really well and apply brazing flux.

 

Then I heat with a MAP gas torch until the brass just starts to turn red.

When I apply the silver solder to the joint, the silver beads up and rolls everywhere EXCEPT into the joint.

I've tried brazing a cooler and hotter temps and get the same results every time.

 

Can someone help me?

I really need to learn to braze brass butt joints (20 gauge brass).

[Steve Sells]

IF and a big IF you are using the terms correctly thats way too hot for solder, also you started off talking about braising that is a different thing entirely, cant braise with solder

[Frosty]

oldering cartridges brass to base, or are you just using C260 brass stock? Brazing/silver soldering, hard or soft is all pretty much the same process and rules. Butt soldering is always iffy unless you have a large joint surface. Soldering cartriges base to base should be easy.

Remove the primer, spent or not it's iffy and may give off goop to "poison" a solder joint when heated. Easier to just get rid of it. Shine the base up, steel wool or sand paper. Use a good quality acid flux or acid base paste and TIN the cartrige base.

When heating do NOT get the flame on the joint and heat evenly around the cartrige. When the flux starts smoking begin just touching (brush) the base with the solder. It'll flow when it's ready only put on enough to cover the base evenly.  

Tin both bases, shine up the solder, flux, clamp them together as desired and heat BOTH cartriges at the same time, again NOT aiming the flame at the joint.

That's just for soldering, hard or soft. However as Steve just pointed out, you're mixing terms and as asked your question can't be answered. And NO, red heat is NOT right, you're NOT brazing steel.

I wish you'd posted that before I had this mostly written Steve.

Frosty The Lucky.

[Marc1]

The terms are used interchangeably and lead to confusion.

Silver solder is a generic term that means little. Brazing or hard soldering is done with a silver copper and phosphorus alloy that melts at 700 C more or less 1300 F and you need an oxyacetylene torch for that. The rod used for brazing is called Silver Solder because it actually contains silver.

Soft soldering, that is also called silver solder due to it's colour, that is not brazing is done with a soldering wire or a bar that contains variable amounts of lead and tin. In this days of sugar free coke you can buy lead free soldering wire with tin and copper as alloys. The main difference with soft solder is the melting point that can be as low as 120 C and up to 400 C. Big difference. If you overheat the piece the solder will boil and pop all over but where you want it. Soft solder melts at very low temperature, Check the label of the one you have. The more tin the lower the temperature. Heat up the cartridge, (hopefully spent and with no primer  ) just a little and touch it with your solder wire and the flame away. If the wire does not melt, give it a bit more with the torch. Just a little! and keep on going until you reach melting point for your solder. Too much heat and you just make a mess not a joint. The idea when soft soldering is that you heat the piece and the heat in the piece melts the solder. You don't heat the solder with the iron or flame. And you don't overheat. 

 

 

[ytuyuty]

Ok

So I am trying to securely connect brand-new shined and cleaned 20 gauge brass sheet. Butt joints, shined and clamped.

So I need to get a oxy torch instead of a MAP torch, and dedicated brazing rods and nstead of silver solder. Is that correct?

I tried heating slowly, but the solder doesn't melt when I touch it to the brass.  I really have to heat the brass pretty hot (red) to get the solder to melt on contact. I have also tried adding heat slowly, waving the flame in and out but the solder just beads up and rolls all over the place except into the joint. No matter if I go cool or hot, the solder beads up and rolls everywhere except where I want it to go.

Ive even tried a pencil torch to use a lower heat and a more focused flame. Same results. 

[BIGGUNDOCTOR]

There are a bunch of different alloys used for soldering. What are the specs for the one you are using? As mentioned before temps range from low to high. Try this experiment. Take a piece of say 1/8" steel, put a piece of your solder on top, heat it up from underneath until the solder melts and actually flows to see how hot you need to get it.   Also, is your flux compatible with the alloy you are soldering with?  I used some silver solders that needed a bright cherry red to flow.

Look up a product called Force 44, it is a low temp silver solder used in gunsmithing and melts in the 400F range.

[Frosty]

No, you can't butt solder 20 ga. brass sheet. You can't "solder" brass with brazing rod. You don't use oxy fuel torch to solder brass. I'm only addressing those mistakes to make the below point. 

You have things so mixed up here I don't know if I can help.

If you have a welding supply close by take a sample in and ask the guys at the counter. They'll sell you what you need and give you an idea of how. Might even give you a quick lesson in back. For now you don't know enough to ask questions that're even in the ball park nor understand the answers.

Frosty The Lucky.

[Marc1]

Harry, you are funny. 

Don't despair, soft soldering is relatively easy so my guess is that you have the wrong solder, the wrong flux, the wrong heating tool and no practice. 

All can be overcome with a bit of patience.

Frosty's idea to go to a welding supply seems like a good idea. if the desk jockey has experience and this can be a big if. Then again, you may be in luck

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Brass can be soft or hard soldered with the right alloy and the right heat. Brass wire solder according to this supplier has 38% silver and the rest is brass, so I gather it would be very expensive, and I wouldn't tell anyone to use an oxy torch without experience. 

Try practicing with a soldering iron and some soft solder wire with it's own flux to get you started, may be some copper cable, copper tubing then try a few offcuts of that material. 

[ytuyuty]

8 hours ago, Frosty said:

You have things so mixed up here I don't know if I can help

My, my, someone asks for help and you're one helpful pal. Have a nice day. 

BTW once I did successfully braze or solder 20 gauge sheet brass, butt to butt, using this technique, but I got lucky, don't know how I did it, and can't do it again. And 2 years later the connection is still doing fine. So your claim that 20 gauge brass can't be butt soldered is false, obviously you don't know what you're talking about, and I can't help you. 

[ytuyuty]

On 2/10/2019 at 1:45 AM, Marc1 said:

 

Thanks for the info.

What I made before was a non-weight bearing butt joint, just a cap, shown in the photo. But now I need to make another one with a 1" brass ring on the seam that will need to hold 5 pounds nominally, and 10 pounds with bounce stress. It's got to be cosmetically pretty.

Do you think solder would be strong enough? Or do I really need to learn to braze this?

Thanks Marc

[Latticino]

I don't see a cap, or a photo.

As others have indicated, soldered joints will be weak in an edge to edge, butt joint for a very thin gauge like 20 ga.  In a true butt joint (edge to edge) you will be relying on the strength of the solder to hold the two edges together.  There will always be a seam and it won't be aesthetic unless your two brass edges are really good and even then there will be a thin silvery line that many folks would find a defect.

On the other hand, if you are trying to make a lap joint, the increased surface area will certainly help with the strength and may hide the solder.  I would give up on big box store solder and flux and switch to jeweler's supply solder.  Actually for the type of joint you show in your sketch (if I am interpreting it correctly) I would probably rivet the joint for the ring carrier rather than either solder or braze.  If I were wrapping the sheet brass to solder the longitudinal seam I would scarf the edges for extra surface area then solder it using jeweler's silver solder (probably the lowest temperature I could get, unless I really planned on soldering on the ring holder).  Then I would finish forming and clean up the joint with files and sandpaper.

I wouldn't try to braze brass that thin for fear of melting holes at the temperatures needed to run the sacrificial brazing rod.

But that is just from taking one basic jewelry class 20+ years ago.  Using the correct terms when asking questions helps those trying to assist you.  How you phrase and frame a question will have a significant influence on how and who will decide to answer it.  This reminds me of the perennial Passover story about the four children.   Unfortunately I've seen too many original posters get their backs up when they don't get the response they expect and alienate some of the more knowledgeable and dedicated forum participants.  

[Steve Sells]

asking a poor worded question then get rude with a person that tried to help? OK i see, If you know so much about it, why waste our time asking us questions?

 

 

[ytuyuty]

1 hour ago, Steve Sells said:

asking a poor worded question then get rude with a person that tried to help? OK i see, If you know so much about it, why waste our time asking us questions?

If I knew enough to ask intelligent questions about this matter, then I wouldn't have asked for help. I am diving into a new realm, have read a lot on the matter, but still cannot understand what I am doing or what I am doing wrong.

Is that too difficult for you to understand?

Is this a forum for sharing information?

Or merely forum where experienced people can stroke their egos by talking down to people who don't know as much as they do?

Serious questions, all 3 of them.

That Frosty guy has one serious bad attitude, and its not the first time I have seen that behavior from him on this forum.

[Steve Sells]

It was explained you need to use recognized terms to communicate properly.

we all need to use the same terms in the same way, in order to share information.  There are established terms you are misusing,  you dont try to use them in a manner the rest of us can understand. so we cant give you an answer you can unsderstand

[ytuyuty]

You didn't answer any of my questions.

[Glenn]

28 minutes ago, Harry Marinakis said:

Is this a forum for sharing information?

You have been provided information, have you taken it to the forge and try to use it to see if it works? 

The welding supply should have suggestions, and have the products you can use, or recommendations to help. Have you taken your project to a welding supply store and as for their suggestions?

[Marc1]

Harry, 

13 hours ago, Harry Marinakis said:

Do you think solder would be strong enough? Or do I really need to learn to braze this?

The gage you are using is not ideal to butt join however the shape of that cup should aid in the strength department. Hard to say without experimenting. If I were to make something like that I would tig braze it, or oxy/acetylene braze it. 

Latticino has given you good pointers and riveting is a good idea. The say goes ... if you can't hide it, feature it. This is the sort of job that you need to work out by yourself or, talk to someone who works regularly with brass. I don't. 

I still don't understand why your recent attempt failed. Do you have a picture of the solder and flux used?  

[Frosty]

4 hours ago, Glenn said:

The welding supply should have suggestions, and have the products you can use, or recommendations to help. Have you taken your project to a welding supply store and as for their suggestions?

Obviously not Glenn; they have FREE books if the guys at the counter can't answer the question. In the USA anyway, almost every person I've ever talked to in a welding supply knew the subjects well or would yell at the guy present who did. Lacking that they'll crack a book, look up the answer and explain for you. If it's a slow day take you to the back room and give you a hands on lesson. 

Harry: I'll do my best never to inflict myself on you again. Unfortunately I'm a reguar poster here and not stopping so please put me on your filtered list.

Adios

[ThomasPowers]

For ease of use and availability I  would look into the rods that are used for refrigeration repair---like sil-phos

[Latticino]

My best guess on the mode of failure, based on the somewhat misleading description of his process, is that he got the solder too hot for the substrate he was trying to weld.  Rather than thoroughly mechanically cleaning the joint with an abrasive to get a shiny surface, then fluxing and heating slowly from the back of the joint, I suspect he got antsy when the solder wouldn't flow and used the torch on the close side of the joint.  The large Mapp gas flame would quickly overheat the solder and push it around on the surface of the substrate.  Properly cleaned and heated the solder should melt and run towards the heated joint.  Use of solder that melts at a lower temperature will make it easier to solder the joint, but will make a weaker joint. 

Again, recall that I'm not mentioning brazing (while making joints in refrigeration tubing with hard silver solder is called brazing in the industry, for ornamental fabrication I believe it is more proper to call what you are attempting a solder joint).  Unless you have very good flame control skills, and a torch that puts out an extremely hot, but small flame  I wouldn't consider brazing for a butt weld on this thickness.

[arftist]

Lots of issues here. 

A few facts; silver brazing (also correctly know as silver soldering or hard soldering)  as mentioned, melts at at least 800 degrees. 

The term "joints" has been thrown about, however there is no such thing as a butt joint for soldering. There is a welding joint known as a butt weld.

If one had access to a TIG, one could TIG weld the joint with brass or preferably silicon bronze rod. However, the material is very thin for welding.

Finally, there are silver bearing solders that melt at lower temperatures ( below 600 F.)

 I recommend the use of just such a solder. 

Soldering is easy when done correctly, yet impossible to do when not done correctly. 

To the OP, something is only considered doable when it can be done repeatedly.

Since you can't recreate your beginner's luck, it is you that is incorrect, not Frosty.

Frosty has forgotten more than you will ever know.

 

[ashmancometh]

Hi Im new here and I started a project a while back and got frustrated with it and distracted and completely forgot about it. Im now back to it, and it 2 pieces of 260 brass brazed together with 56% silver 44% tin and the one thick piece never stuck and I heated it well. The problem was I didn't add enough solder to the piece I think or I needed to place the pieces upside down. But my question is: Now that both pieces have some solder and charred black flux on them, how do I proceed? Should I sand some of the flux and solder off (flat even?) and start fresh? Or put the 2 pieces in a citric bath? It has been around 7 months since I touched the pieces so some things could have oxidized....

 

Any ideas helps, thanks

[Irondragon Forge ClayWorks]

20 hours ago, ashmancometh said:

Im new here

Welcome aboard, have you read this yet? READ THIS FIRST   It will help you in getting the best out of the forum.

[arftist]

Ashman; you need to send all the flux off but it is not needed to get all the solder off. I would sand till you can see some brass through the solder.

[Irondragon Forge ClayWorks]

You could also tin both pieces. This video explains it using a copper but a torch will work as well. Just heat the pieces till the solder melts them wipe it off.

https://www.youtube.com/watch?v=vDVaO3_CaiA