Wednesday, 5 February 2014

How To Make A Simple Metal Ring



Shiny!

This simple ring is a great way to start to learn how to work with metal. I've tried not to use too many specialist tools, so this should be - hopefully - helpful for beginners.

Things you will need: metal, silver solder, blowtorch, hacksaw, emery cloth (or wet-and-dry paper), hammer.

Things you don't need but will make life easier: file, solder flux, nylon/rawhide mallet, power drill/lathe, ring mandrel, ball pein hammer.

First up, metal. Almost anything you can buy in sheet form is OK, I'm using copper because it's cheap and fairly easy to work with. Brass would be another good option, maybe even silver if you're feeling wealthy. I buy my metals from Cookson Gold in the UK, other suppliers are available.

Note: aluminium is not suitable, it melts at a lower temperature than the solder does.

Using some Maths (2 x pi x (r + metal thickness)), or this useful calculator, work out how big you need your blank to be, and mark and cut. I'm using a jeweller's piercing saw here but a hacksaw will work fine.


Once you've cut your blank, file off the rough bits and make sure the ends are nice and square and clean. Clean is very important, solder won't bond to dirty, oxidised metal.


Carefully and gently, bend the blank around into a rough ring shape so the ends are touching. They should meet closely enough that you can't see a gap between them. If they don't meet, unbend a bit and file again until they do. Spending time getting this right will save you time later on.

Once they meet, bend them slightly past each other, so when you pull them back into place, they're pressing together a bit.


Place the ring on your heat-proof pad (or brick, or lump of metal or whatever) and give it a nice sploosh of flux. If you don't have flux, don't worry too much, but do make sure the join is as clean as you can possibly get it.


Now cut a tiny piece of silver solder and place it on the inside of the join. Note that silver solder is not the same thing as electrical solder - it has a higher melting point and is much stronger. When you apply heat, apply it everywhere but the piece of solder. You want to get the metal hot enough to melt the solder, not use the torch flame to do that. If the metal melts the solder, it will flow properly into the joint and make a strong, clean join.

If your torch flame melts the solder, it will likely roll off the cool (relatively!) metal and won't form a join. Solder can be awkward stuff.









You can't see the flame here, but this torch is lit. It's one of those little butane torches you often see sold as 'cooks' blowtorches. They're not expensive. You could use a plumber's torch but they're very hot and you could easily melt your copper if you're not careful. Not that I've done that. Not at all. (woops!)


In this image you can see how the solder has fluxed and run smoothly over the join and the surrounding metal. Tidy. The copper is only temporarily discoloured by the heat, we'll deal with that in a moment.

At this stage some people will say you need to 'pickle' the piece, or soak it in warm acid. This will remove all the discolouring caused by the heat, but you can do the same thing with a bit of elbow grease and some emery paper (or wet-and-dry paper). Pickle is fine if you have it, but I'm trying to keep this simple.


Bashing time! This is a specialist tool, I'm afraid. It's a tapered steel rod called a ring mandrel, or triblet. I haven't found anything which can substitute for a triblet unless you happen to have a piece of metal or dowel the same size as the ring you're making. Of course it's not too hard to put a taper on a piece of wooden dowel, but it won't work quite as well.

The nylon faced hammer is there so as to not mark the metal, but you can use a normal hammer with a few layers of electrical tape on the face (and a light touch!)

You don't need to hit hard here, gentle is better. The copper will be soft from having been heated - even after it cools down. This softening due to heat is called annealing, and by hammering out the ring you work harden the metal a bit which makes the ring stronger.

For this reason, some people prefer to do the rounding-out last, I find it easier to do it first for reasons which will become clear. I'm lazy, basically.



Run the ring up and down a file a bit so it's all nice and level and square. I tend not to use a file on the face or inside of the ring, but it's up to you. You'll find a way which works for you.

Now on to why I like to round off my rings before I clean and smooth them.... a turning jig.


Here I have some 180 grit emery paper taped to a screwdriver bit, in a power drill clamped to my bench. This makes it really easy to polish the inside of a ring - just spin up the drill and hold the ring to the spinning paper. Told you I was lazy.


The whole setup. There's a G-clamp holding the handle of the drill on to the bench. The socket the ring is on is wrapped in masking tape until it's thick enough to friction-fit the ring onto it. Boy, does this setup save effort.


Shaping and polishing the ring. Working down from 180 grit to 1500 grit, paying lots of attention to rounding off the edges of the piece. Doing this by hand would take ages, even with copper which is fairly soft.


More lazy polishing. You don't need to use jeweller's rouge here (the red bar in the background), but I happened to find some in my local hardware shop and thought I'd give it a go. It's good, but any fine polish will give you a mirror shine - products like Autosol, Brasso and others are all fine for this job. The buffing wheel is useful, but far from essential. They're not expensive though, so worth getting if you're doing more than a few rings.


Shiny! You can stop here, if you want to. Copper will tarnish with time, but you can apply a poly varnish or wax seal or something similar to slow the process down.

However, I have plans for this ring. Hammer plans!


Again, (moderately) specialist tool. A ball pein hammer. Note the clean, polished, rounded head. Keeping tools clean is important, any marks or scratches will transfer to the piece and you might not want that.

You can do this texturing with a 'normal' hammer, but this little thing was cheap and it works really well. Slip the ring back onto the mandrel and have at it. Bang bang bang bang!



A quick buff with a soft cloth and we're all done. Pretty!

As ever, a blog entry wouldn't be the same without a link to my Etsy shop, where rings like this one and other styles are for sale. Custom orders are always welcome, and I never charge more for commissioned pieces.


With thanks to this excellent Instructable.

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