Hinges. Again.

[medusa]

I have had several requests to make either collars or bangles out of round stock with a kind of concealed hinge/closure. I've seen versions in steel which use a kind of lapped pivot hinge but I'm worried that the silver would maybe be too soft for this.

I'm also not sure the best way to go about this... Logic says I should shape the silver rod first as close as possible, disassemble to make the closure and ensure it is flush, reassemble and give a final shape to it.

I've had so many requests for these now that I know I'm going to have to attempt it, but don't want to go in blind. any advice welcome.

[Dennis]

This this not a project for beginners, Liz, but what you are asking about is a sophisticated version of this cheap and nasty key ring, with a smooth hinge and a flush rivet. The hinge must be strong enough to resist the torsion of the catch.

Only by browsing books on hinges and catches can you come up with something within your ability, and then you must practice with base metals first. But as you rightly suspect, to be viable in silver, the gauge must be quite heavy. Dennis.

[Goldsmith]

Liz have you considered making a hinge section out of tubes as a pattern that could be cast for repeated use on the collars and bangles.
James

[medusa]

Ahhh Dennis, I do know my limitations so well! Thing is, I haven't seen any hinges of the kind I want to make in any books so far (though I'm stuck with my local library and what is there on google at the moment). The catch needed isn't really a catch as such because people have been asking me to make them so they screw shut. The gauge I've been asked for has been from 8 to 10mm. And yes, I have told people that it will be really really heavy and expensive!

I've got some copper rod coming my way to play with, but I'm a tad cheesed off at having to turn work like this away which is why I really need to get it sorted.

James, I know that the kind of collar/bangle people want is a super smooth fluid piece. I don't think that kind of hinge section would work, but then maybe I'm not visualising it correctly.

If anyone wants this in the meantime, give me a shout.

[medusa]

Well I have my copper rods and I also have version of the kind of thing I want to make on the way to have a good look at the hinge construction. I'm assuming that the first step before cutting the hinge would be to form the copper into a circle. Given that this is quite a large diameter, what would be the best way to go about this? Roughly shaping and soldering shut and then shaping on some kind of mandrel, or would I be better trying to bend the metal on a jig?

[ps_bond]

There's a really good e-book by Charles Lewton-Brain on the subject of hinges, FYI. Not expensive for what's in it - but of course you can't easily browse it first.
If I'm visualising what you're after correctly, I'd probably form the circle with a decent overlap (to allow for the hinge) so a jig might be a better bet.

[medusa]

I've seen some of the stuff on ganoskin, as it happens, someone is getting a kindle for christmas...

[Dennis]

If you could post a photo of what you are aiming for, we could chip in with more relevant advice, Liz.

If you are aiming to bend the end of a piece of hefty wire into a ring shape there are physical limits on how small you can make the ring, unless you also file it to a long taper to reduce the thickness. You will certainly need to bend it around something, with some excess length for leverage , to avoid plier marks.

The alternative is to beat the end flat, shape a disk, and drill the centre. When you first wrote about this I visualised a hinge completely invisible, like for the nose ring of a bull. Dennis.

[Goldsmith]

Well I have my copper rods and I also have version of the kind of thing I want to make on the way to have a good look at the hinge construction. I'm assuming that the first step before cutting the hinge would be to form the copper into a circle. Given that this is quite a large diameter, what would be the best way to go about this? Roughly shaping and soldering shut and then shaping on some kind of mandrel, or would I be better trying to bend the metal on a jig?

Hi Liz,
Take a look at these plumbers pipe bending tools, I think one of them may suit your purpose of bending the circles of wire, see these pipe benders from Screwfix;http://www.screwfix.com/c/tools/pipe-bending/cat831338
James

[medusa]

Thanks both.

Dennis, I am aiming for the kind of hinge you would get on a bull nose ring, but neck sized. Something like this:

http://www.cuffstore.com/cart/images...sed-800-05.jpg

but minus the rings and stuff.

James, I have a friend with pipe benders so I'll have a go with his on the copper.