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April 6

Welding two copper pieces together.

I have a project to design. I need to know if I can ask a manufacturer to weld a piece of copper wire to a copper ring. Thanks AboutFace 22 (talk) 21:59, 6 April 2019 (UTC)[reply]

...What do you think will happen if you ... just ask them? In most parts of the developed world, prospective customers don't get penalized for asking questions, even if the questions are ill-formed.

Of course it can be done; the important follow-up questions will be about cost, schedule, and any special requirements you might have. Do you have mechanical tolerances? Do you have any special requirements? Do you need to avoid using any chemicals or metals during processing, or avoid stressing or heating the parts? If you don't even know these answers, do you plan to hire an outsourced consultant, engineer, or technician, or machinist, to step in and manage the work?

You can contact a local or outsourced machine shop to see if they'll handle an order of your needs at your price-point. Big manufacturing shops will have a salesperson to answer questions; little shops might just have the machinist or welder talk you through the work and its costs.

Nimur (talk) 22:11, 6 April 2019 (UTC)[reply]

There are different ways to join two pieces of copper. Welding joins metals by using high heat to melt the parts together and allows them to cool causing fusion. Brazing joins metals by melting and flowing a filler metal into the joint, the filler metal having a lower melting point than the adjoining metal. Soldering joins metals by melting and putting a filler metal (solder) into the joint, the filler metal having a lower melting point than the adjoining metal. Wire wrapping makes a mechanical join without use of heat. DroneB (talk) 12:54, 7 April 2019 (UTC)[reply]

We have yet another article, wire wrap, which provides even more detail about wire-wrap methodology as it pertains to electronics, (as opposed to the separate article on wire-wrapped jewelry, linked by DrobeB). The wire wrap article includes details about making good electrical connections. Specifically, the shape of the post, and the tensions of the wire, help to ensure a statistically-clean wire-to-post joint with good-quality dc- and ac- electrical coupling - something quite distinct from good mechanical coupling. Along the same line: any joining method will impact the electrical or electomagnetic impedance between the parts, with special factors relating ti the geometry and quality of the joint, the presence of an interstitial metal or impurities, and so on. Nimur (talk) 18:36, 7 April 2019 (UTC)[reply]

Welding copper is hard. Brazing or silver soldering copper is far easier. Copper is very rarely welded. Andy Dingley (talk) 13:04, 7 April 2019 (UTC)[reply]

I'd recommend starting by checking to see if there is a makerspace or (depending on country) a men's shed in your area that supports welding - the job is a simple one depending on the type of weld, so you might be able to get some assistance from them. If so, you are probably looking at brazing as your first choice, as that's a relatively easy way to join copper, but arc welding may also work (per Andy Dingley's comments it is very hard, though, as the copper will draw the heat away). For brazing you only need an oxyacetylene torch, which is something a makerspace might have. Otherwise a small workshop should be able to do it for you. - Bilby (talk) 13:13, 7 April 2019 (UTC)[reply]

Thank you, everyone. It is very valuable. I have no education or experience in the area of discussion but I have a major project and manage already to receive four USPTO patents in the past 5 years on various parts of it. This is the last part. I can answer some of the raised issues, although you don't necessarily expect answers. Tolerances will be liberal, demand to avoid overheating, yes, it should be avoided as much as possible.because some sensitive plastic or composite material might be in close proximity.

I am in the United States, big industrial city and after googling I can see that there are quite a few shops almost next door, offering to do industrial prototyping. Besides my patent attorney recommends one of them. And how about silver instead of copper for the ring? But the wire, I doubt it could be made from silver, the wire must be more durable. It will need to be pulled as part of the job description. The parts are expected to be small, perhaps close to half an inch for the ring diameter or slightly more.

So, how about attaching a copper wire to a silver ring? What process shall be used? I want to approach the shop owner/manager with some definitive recommendation, although I will expect them to recommend something different, perhaps, based on their experience.

I need to study your answers more. Thank you again. I think you instantly added 5 years to my education in the area industrial design. AboutFace 22 (talk) 14:59, 7 April 2019 (UTC)[reply]

This is simple stuff. If silver is credible as a material, then silver soldering is likely to be the technique of choice. Are we talking jewellery or engineering here, as you've not mentioned the sizes.

Learn some basic silversmithing and you're away. The standard book is by Oppi Untracht and there are many local college courses etc. Or find a Hackspace. For tooling you need little more than a cook's gas blowtorch and a firebrick, certainly not oxy-acetylene. For copper (for which you'd use a higher melting point solder) then you could use a natural draught plumber's gas blowtorch. Silver BTW is rarely used in the pure form as it's too soft - far more common is to have it alloyed with copper as 'Sterling silver' or other alloys (so you can tell that copper and silver work well together). 800 silver (80% silver, 20% copper) is a good alloy if silver is going to see any wear as it's much harder-wearing, but the jewellery makers would look down on it. It's not rocket surgery, you can learn this stuff on a kitchen table, but it's easier if you go and visit a silversmith who's already equipped, then starting cold. Andy Dingley (talk) 19:27, 7 April 2019 (UTC)[reply]

@Dingley, thank you. You provided more useful information for me. No, it is not jewelry. It is a mechanical device, afraid to name it, not sure about rules for patenting. Today is Sunday, cannot reach my patent attorney, but it is also probably unnecessary. I just ordered "Metal Techniques for Craftsmen" on Amazon. - Thanks again AboutFace 22 (talk) 19:49, 7 April 2019 (UTC)[reply]

Andy is right about needing just a natural draught plumber's gas blowtorch - I was expecting a more impressively sized ring, but I tend to work on a larger scale. :) You can grab them very cheaply at any decent hardware store, as they are used for brazing copper pipes using in plumbing. I've found them to be very easy to work with. - Bilby (talk) 06:21, 8 April 2019 (UTC)[reply]