Tube setting cabochons

[silken]

Hi everyone!

This has been an ongoing issue for me and a leading cause of frustration in my little studio so I thought I should finally ask and see what other people suggest. I love tube setting and often set faceted stones with no problems at all. However, cabochons are slightly more pesky as they like to spin/overturn in the setting once the seat has been cut making it rather difficult to set them. I usually cut the seat with a ball burr then finish with a setting bur but the cabs hardly ever co-operate. I have resorted to cutting a level seat with whatever burr/sharp tool I can get my hands on (I don't have any gravers, I know, I'm terrible) but I'd love to hear if anyone else has any methods for tube setting cabs. I'm off to the jewellery quarter in the morning to visit cousins, cookies, sutton tools, the usual and I was thinking about getting some plain cylinder burrs to try out as I'm sure if I start cutting a seat with a ball burr then finish with the cylinder burr, I might just get a nice level seat.

Any suggestions will be greatly appreciated

[ps_bond]

If you want to cut a flat bearing/bezel shelf, can I suggest the use of a small inverted cone burr? Unlike a cylinder burr, it won't try and cut the full length of the bezel wall at the same time as the shelf.

[Goldsmith]

Hi Emily, I don't know what size cabs you are setting. I prepared this set of photos a while back to show my method of making a tube setting for large cabs. You can use this process on smaller tube settings and use jump rings as the stone seat.

James

[Dennis]

You have my sympathy Emily, I am well aware that small cabs will suddenly turn turtle in tubes, if you can't control them with a fingernail and the only remedy is to have a good flat seat instead of the sloping ones for faceted stones.

Peter's idea will rectify this, but some suppliers such as Walsh sell burrs specially for this (Walsh FIG 4120) As with all expensive burrs, it saves on wear if you start with a ball burr first and then use the special burr by hand in a pin vice with a drop of oil.

With small stones or on unsupported areas I also like to pinch the tube at least to begin with, using round/round or round/flat pliers, which quickly captures the stone. Dennis.

[silken]

Thanks so much for the replies! James, those photos are wonderful! Thanks so much for posting. I usually use fairly thick walled tubing and cut the seat with ball/setting burrs so this technique would be great for setting the larger cabs that I usually just bezel set.

The cabs I most often tube set are small, varying from 3mm - 5mm but I do have difficulty trying to get them to sit down and behave! Anything above that size I usually just make my own bezels but James' pics have inspired me to start tube setting larger cabs!

Peter, that's a great idea! I didn't even think of using inverted cone burrs, all I had in mind was the cylinder burrs but thinking about it the cone burrs should be much more efficient. Dennis, I think I'm being stupid as usual but I can't find that reference anywhere on Walsh's website. Do you have a link to them at all? I didn't go to the jewellery quarter today after all (long story, involving someone trying to steal my car and having to deal with the police for most of the day) but I'm going tomorrow so if I can see what I need to look for that would be wonderful.

I really do appreciate all your help

[Goldsmith]

Emily, Cookson sells the inverted burrs, see; http://www.cooksongold.com/Jewellery...prcode-980-090

The way I showed of making stone seats works well for large diameter facetted stones also. These are a few of my daughter's silver bezel set rings, the facetted stone is a lab grown 12mm. diam. pink sapphire, the others are blue lace agates.
James

[silken]

Wow, those rings are beautiful. I really love the pink sapphire one, the setting is perfect for the stone. You have a very lucky daughter!

I have quite a few burrs that I buy in sets from Rio Grande but sadly no inverted cones so I shall definitely pick some up tomorrow. I was just wondering what the specialised ones from Walsh's that Dennis suggested might be like. Either way, the cone burrs seem like they would do the job perfectly.

Thanks again for all your help!

[Dennis]

Dennis, I think I'm being stupid as usual but I can't find that reference anywhere on Walsh's website

Well, the website is not a lot of fun, so I was quoting from the printed catalogue. anyhow, here it is:http://www.hswalsh.com/Fraizer-.aspx?i=TF41210&c=1203.

These burrs come in various sizes to match you cabs. Sorry you had a bad day, Regards, Dennis.

[silken]

Ahhh! I thought it might be those. I don't have a copy of the catalogue so I have to resort to their somewhat difficult to navigate website. I'm going to get a couple of inverted cone burrs and a couple of those ones and see how it goes. I'm excited that I may soon be able to set cabs without the aforementioned hassle!

Thanks for your kind words, Dennis. It hasn't been the best of days but I'm hoping to cheer myself up by getting some nice new tools tomorrow. I asked my boyfriend for some tools instead of flowers this valentines day and he just sighed and gave me a strange look...a nice new set of burrs lasts much longer than a bunch of flowers, right?

[ShinyLauren]

Emily, I asked for some wire cutters and a takeaway from Nandos for Valentines!

I use the inverted cone burrs for cabs as well - I set really tiny ones, like 2mm, upwards and they cut a lovely flat seat for the stone to sit on.