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Victoria
01-06-2013, 09:00 PM
Hi,
Just wondered if these are any good? Seems to cheap!
http://www.ebay.co.uk/itm/proops-jewellers-ring-stretcher-ring-stretching-mandrel-jewellery-making-new-/111045362374?pt=UK_Jewellery_Watches_FineJewellery _CA&hash=item19dad1c2c6
Thanks
Victoria

Wallace
01-06-2013, 09:43 PM
Hi Victoria,

they leave lots of marks on the inside of the ring. Fine if you have some time to take the marks off, or have some leather that you can put inside the ring before you do use it.

kindest,

Wallace

Dennis
01-06-2013, 09:50 PM
Hi,
Just wondered if these are any good? Seems to cheap!
http://www.ebay.co.uk/itm/proops-jewellers-ring-stretcher-ring-stretching-mandrel-jewellery-making-new-/111045362374?pt=UK_Jewellery_Watches_FineJewellery _CA&hash=item19dad1c2c6
Thanks
Victoria

Many years back I bought one of these out of curiosity. If you think about it a single hammer blow is short acting , quite feeble compared with a steady pull on a lever and likely to glance off onto the supporting hand. So you have to do lots of whacking. The process is very uncontrolled and there is little there that cannot be achieved by tapping on a ring mandrel (except the saving of any surface texture from blows).

When I finally bit the bullet and bought a proper upright ring stretcher, which easily did what it promised, it changed my approach to ring making. I now make my rings about three quarters of a size too small and gently stretch them to size, turning them over to avoid a taper and checking with my ring stick.This also makes them round and does not damage textures on the outer surface. Dennis.

Wallace
01-06-2013, 10:08 PM
must admit Dennis, I do the same, although I still use my A-Z ring stick to help with sizing and shaping thinner rings.

I got myself one of the first mentioned when I started and really did not realise how much padding is needed and how much faffing about would happen and how many wasted items I would go through.

Cheap can be useful for practice. However, for rings really investing a little more will make so much difference.

Victoria
02-06-2013, 11:35 AM
Thank you both. So to use this I would have to hit the ring with a raw hide hammer to stretch? In which case there's no difference between this and just using a mandrel!? I assumed it was some kind of cheap version of the one you posted Dennis...

That's really interesting that you stretch all rings...does this not stretch surface patterns and also any stone settings where the setting is in the band?

V

caroleallen
02-06-2013, 12:07 PM
I've got one that I never use as well Victoria. I'd say save up for a proper one and it'll be money well spent. Like Dennis, I always make my rings a bit too small and size them up.

Exsecratio
02-06-2013, 02:27 PM
So to use this I would have to hit the ring with a raw hide hammer to stretch?

Very similar effect to hammering in a nail (as in the things that hold wood together) the taper of the top pin forces the fingers apart as it is driven into the bottom section. Nice idea, terrible execution.

Hammer blows introduce momentary force, presses introduce applied force. Momentary force will allow more springing back of the job than applied force (the material has no time to realign it's structure when subject to hammer blows)

Couple of other things that may be a problem, the number of fingers (slots) is quite low so it's probably going to mark your Ring quite badly, the surface finish on the expanding part is rubbish (machining marks anybody?)

Looking at it, any Engineers here will think of internal mandrels used to turn the OD of tubes in a lathe, for that it would be great, for reforming a fine piece of hand crafted artwork made by an Artist here.....not a hope.

Has anybody here used Barnes Stretchers? don't know if they would work on Rings but they work well on cartridge cases and best of all they are free to make and don't deform stuff :)

best wishes

Dave

art925
03-06-2013, 12:25 PM
Hi Victoria,
I also use the upright ring stretcher, I have never seen this version you post before. However, rather than hitting the ring stretcher with a hammer, could it not be positioned inside a large bench vice. As the handle is turned, will this not provide the constant gentle stretching effect as the upright?

Les

Exsecratio
03-06-2013, 02:43 PM
Barnes Stretchers:

4802

Used to bell case mouths on custom gun cartridges but should work well on rings as well.

The rubber should be a push fit in the ring and be around 2mm thicker than the width of the ring.

Tightening the bolts causes the rubber to expand (very evenly) and applies high force but low impact.

Dirt cheap to make :) pretty much throw away too :)

best wishes

Dave

ps: The design was by the late Frank C Barnes (all credit to him) many years ago when custom case dies were both expensive and hard to get hold of.

Dennis
03-06-2013, 05:34 PM
Well the point about the real thing Dave, is

1. That it has quick release for removing the ring.
2. The ring travels down a calibrated column, so that you can see just how much yo have stretched so far.

Admittedly you also have to check with your standard ring stick as the marks on the column might not correspond. Making rings can be a nightmare, or a pleasure, depending on the sophistication of your method.

Exsecratio
03-06-2013, 09:34 PM
Agree totally Dennis :)

I was thinking more of the original item (the tube mandrel,...I mean ring stretcher) ;) the thought of murdering a piece of craftsmanship with such a tool would give me the shivers :)

I understand there may be budget constraints on any business and cheaper tools often have to make do (or can be modified to make do) but my Late Father taught me from a young age when trying something new or technical "don't spoil the ship for a hapeth of tar" and "shortcuts are justification used by those wishing to leave bits out".

I read round these forums as a new guy and see the things you people make, pretty much all the time my jaw drops with envy at such skill, such attention to detail and crafstmanship then I see something like that far eastern made abomination at the top of the page and have this gut feeling that such items shouldn't even exist let alone be offered to Artists like yourselves.
To have even 10% of the skill you guys have is something I can only wish for without any real hope of gaining.

best wishes

Dave

Dennis
04-06-2013, 12:16 PM
So why not make a start, Steve? You're already an experienced metal worker and there will be lots of designs lurking in your subconscious. You will surprise yourself.

Here is the first thing I ever made, scanned in from a print dated April '94. The teacher handed me a piece of brass and said: draw a design and make a ring. It is always in my toolbox for luck. Joining a class to learn the basics is highly recommended though, as it saves too many futile experiments. Dennis.