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Melanie De Castro Pugh
30-07-2011, 02:45 PM
Hi folks, sorry if this has already been asked, I did search the archives but couldn't find the answer!

I've just bought Sonia Cheadle's stone setting book, and have a first attempt at a claw setting pickling as we speak, but what I'm most interested in is cutting the little notches for claws and carving bearer shelves for rubovers. I had a look in the Cookie shop, but there's so many, I don't know where to start! I figured that cutting into chenier would require a burr exactly the size of the stone, but what size would I need just for notches and carving?

Thanks, here's hoping for some enlightenment...

Dennis
30-07-2011, 05:03 PM
Hi Melanie,

Setters vary in what they do, so no doubt the members will differ. The notches in claws can be started with a saw blade just level with the girdle of the stone and completed with a triangular (three square) needle file, or one of the bearer cutters (Cookson 942 series). You need cut less than half way through the prong, but as you can guess some practice on cheaper material is needed to get it right. Small prongs are best made of gold as silver is not strong enough under about 1.5 mm diameter.

Seats for tube setting are best started with round burrs as they are cheaper and vary in width according how deep they are inserted, so they are more versatile. Many setters go no further, but you can then finish with a dedicated burr, which you don’t want to wear out too quickly, used by hand in a pin vice with oil as a lubricant. For faceted stones this would be the stone setting burrs, listed by Cooksons as Bush 413.

When tube setting cabochons, they have a disconcerting habit of turning over half way through, so to resist this they need a flat seat made either with a graver, or a flat ended burr such as Walsh’s FIG412 also by hand with lubricant.

Kind regards, Dennis.

ps_bond
30-07-2011, 05:13 PM
Hi Mel - "it depends". You can burr into a claw setting with the right size setting burr cutting all the claws at once, you can cut into the claws individually with Hart burr or you can use a 3 square (triangular) file to notch them. The last one is slowest, but gives the most control.

Looking at P47 of Cheadle, she seems to show a round burr being used in the sketch, but the text says a setting burr; I'd probably choose an inverted cone burr for cutting the seat, but later on P52 she does specify a round burr. That said, I'd grab a bullstick scorper first now as a result of Tom's setting course! There's loads of ways to do this - none of them are wrong if they do the job.

Looking further at P52, her description includes using a flat scorper to refine the bearer - here's another area where the careful use of an inverted cone burr can excel, although again, if I've got room to get the tool in I'd be using a flat too.

It's an interesting book; I probably prefer Cogswell myself, but it's useful to have all the references.

ps_bond
30-07-2011, 05:15 PM
Yet again I end up echoing Dennis :D

Dennis
30-07-2011, 05:53 PM
Peter and I are playing Box and Cox just now, but I have come back to add my usual rant about callipers. Setters work mainly by eye, but as an eternal amateur, I like to know what I am doing in millimetres, particularly as stones of a nominal size can also vary.

Digital callipers are easy to read and there are often bargains in discount stores such as Aldi and Lidl and also Maplin. I like the smaller 6” ones as they are more comfortable to handle. Some people find them difficult because, rather like kitchen scales, they need to be returned to zero before each use.
Dennis.

Melanie De Castro Pugh
31-07-2011, 03:08 PM
Thanks so much, I've got a better idea of what it's all about having read your replies.

Doing a little shopping, in my Cookies basket I have a 2-cut three square needle file with an 80mm wooden handle; a Burr:busch 2 Inverted 1.0mm and a Burr:busch 414 Bearing Cutter 1.2mm. I figured smaller sizes would be better as I do quite small things, using stones around the 10mm or smaller mark and that it's easier to use a small tool in a big space than the other way around! Would these be a good choice, do you think?

What sort of scorper blade/combo would be a good first buy for the enthusiastic amateur? One of those length of string questions, I know...

Thanks also for the advice on calipers, Dennis - I have a lovely set from my days as an engineering sales rep :-)

This is my first attempt at a claw setting, nowhere near good enough to sell, but the stone is IN :-)

http://spinysharklythings.files.wordpress.com/2011/07/278785_252824428061309_195671340443285_1138380_181 2721_o.jpg

Joe
31-07-2011, 04:08 PM
I'm not so keen on handles for my needle files and I don't know anyone who uses them. Might I also recommend the rather nice cut 4 needle files from Cookies (976 150 (http://www.cooksongold.com/Jewellery-Tools/16cm-Needle-File-3-Square-Cut-4-prcode-976-150)) as leaving a better finish for places that aren't going to get a second touch.

Melanie De Castro Pugh
31-07-2011, 06:57 PM
I'm not so keen on handles for my needle files and I don't know anyone who uses them. Might I also recommend the rather nice cut 4 needle files from Cookies (976 150 (http://www.cooksongold.com/Jewellery-Tools/16cm-Needle-File-3-Square-Cut-4-prcode-976-150)) as leaving a better finish for places that aren't going to get a second touch.

Thanks Joe - another epically stupid question, is 2 cut finer than 4 cut? Or vice versa?

Dennis
31-07-2011, 07:30 PM
Hi Melanie,
I have become wary of buying tools except when needed for the specific project in hand, so as to avoid building up a tools graveyard.

Once bought, gravers still need setting up, which means shortening them to suit your hand, fitting a handle, grinding away part of the working end and then sharpening them. This was described by James Miller (Goldsmith) here : http://www.cooksongold.com/forum/need-help-ask-experts/3741-cleaning-up-bezel-settings.html.

Coming to the test piece in your picture, it is best if the wire next to the stone is flat which means D-shaped wire, but it could also be round wire slightly squashed ( with pliers, in a press, a mill, or between two steel blocks in a vice) you could also use square wire, or even triangular wire.

Lastly, If Joe has not replied by the time I submit this, re your needle file question: the higher the number the finer.

Joe
31-07-2011, 08:17 PM
Ah, Dennis' words are wise.

But you need to find a way of trying out a graver to see if it suits you. If you don't know anyone or anywhere you can borrow one but have £15 burning a hole in your pocket, you might try a no 8 round scorper (http://www.cooksongold.com/Jewellery-Tools/Round-Edge-Scorper-Size-8-0.8mm-Vallorbe-Ref-402-Ws-prcode-999-AYM) shoved hard into a wooden handle (http://www.cooksongold.com/Jewellery-Tools/Wooden-Handle:shape-A-prcode-999-ALL), without too much fuss about proper set-up or sharpening. I reach for mine as often as I reach for a file to clean-up solder, cut grooves, raise setting grains, draw lines or texture. It is not the tool for bright-cutting or most setting tasks, but it is easier to use than those tools and, I suggest, a good tool to try. These tools respond well to more skill and dexterity than I posses, but can still be useful in hamfists like mine.

If, on the other hand, you can think of something else to spend that £15 on, then leave it on your wishlist and make a mental note to try one when next you visit a workshop.

ps_bond
01-08-2011, 10:02 AM
FYI, the scorpers on the tool list for the course were a bullstick (size 21), flat (size 12), round (size 8) and spitstick or onglette (size 10). The bullstick was the go-to tool for cutting bearings, while the spitstick was mostly used for cutting away metal from the grain settings; the round wasn't really used for anything other than raising grains and the flat was almost exclusively for bright cutting. They're very versatile tools and well worth learning to sharpen and use.

theresa
11-06-2012, 02:34 PM
Hi everyone

I have a question in a similar vein. I am trying to set a 6mm faceted stone into a tube setting & the stone is a tad too high and sitting slightly unevenly. I know I need to deepen the seating but cannot find a 6mm ball burr anywhere. Should I be using some other tool for this job? I understand the principles of this type of setting but as it is my first would welcome any advice.
3651

Theresa

lopez
11-06-2012, 03:29 PM
Hey Theresa, some stone setters would use a ball bur, some a setting bur and some a hart bur, either way it's not the method but the result what matters. In your case looking at the photo the walls look rather thin, therefore pop the stone out if you can, stretch the collet out a touch with a round mandrel if you have one the make the correct seating with a small (<6.00mm) ball drill, file and shape the top of the collet, use a ~1.00mm ball drill to make an notch around the internal diameter where the collet meets the girdle of the stone then put the stone in making sure it's level then push the collet over the stone starting at 12 then 6, 3 then 9 o'clock; when thats all done push the rest of the metal over. File and shape the top, lube the top of the stone and bright cut the inside collet then bright burnish, all good ???

Kwant
11-06-2012, 03:40 PM
I would be lost without my setting burrs, which certainly go to 6mm and beyond I got mine at Fischer in Germany I got this box when it was on special offer.

http://www.goldschmiedebedarf.de/product_info.php?products_id=25560

but they can be bought individually.

Dennis
11-06-2012, 05:10 PM
A full set is rather pricy, but you never know quite which size you will need next, as even stones of the same nominal size will vary when they arrive.

My biggest problem is keeping them in order, so I am forever checking them with callipers. Guess what I shall say next: yes, I think you need callipers as well.

While on the subject of Fischer, they do a useful assortment of round burrs too, the largest being 10.0mm. Round burrs are cheaper to replace and cut faster, so that the setting burrs can be reserved for the finishing touches. Both will cut by hand, assisted by a drop of oil, if mounted in a pin vice. Dennis.

theresa
11-06-2012, 09:54 PM
Thanks to everyone for the advice. I have managed to track down some burrs from Cousins so will let you know how I get on. Examining my stone closely I noticed the girdle is thicker one side than the other which accounts for the uneven seating...more work....and this was supposed to be an inexpensive ring!
Theresa

Dennis
12-06-2012, 02:41 AM
. ...more work....

Not necessarily Theresa, because the difference will be slight and your seat could be a little wonky. So rotate the stone until you find that the table is level, steady it with a fingernail. and start setting.

At worst all you do is slope the burr a little for the last few turns to create a deeper side, or deepen one side with a tiny round burr. Dennis.