PDA

View Full Version : cutting a bullstick to size



lynseysorefingers
01-02-2012, 03:49 PM
I have an rectangular citrine (eight sides) to set in a bezel type setting. i have made the setting tapered toflow with the shape of the stone. i read that you should use a bullstick to cut the metal to hold the stone. i usually use burrs and haven't used a bullstick since art school. Anyway, the bull stick needs cut shorter and sharpened. i remember having to heat the tool first but have forgot the rest! does it really need shortened? can i just sharpen with arkansas stone and get setting?
Also any tips on setting this shape of stone welcome. thanks:confused:

Dennis
01-02-2012, 09:54 PM
Hi linsey, the scorper will generally need shortening to be more comfortable in your hand. You heat only the part to be removed to dull red and immediately quench it. Then you put the scorper in a vice with the now blue part showing. Wearing eye protection,you hit it sideways with a hammer and the surplus should break off.

After that you grind it to a point again and tap on a handle.

However if your bezel is tapered it should be possible to do without any further bearer, provided you can keep the stone level. File down the edges so they stand only about a third of a millimetre above the girdle of the stone and neatly bevel the outside, so that only a knife edge has to be pushed over. As you work to set the stone, the eight corners will begin to pucker , but you can use a fine file gently on the raised bits as they occur. That way no gaps will show. Dennis.

ps_bond
01-02-2012, 10:14 PM
I don't bother heating them - I either hit them with them in the vice (with a paper towel wrapped around to catch the bit I want removed) or use a separating disc to notch them first - or cut through, depending on mood. Whatever works for you, really.

As for shaping, I've been removing the top half of the scorper for about half an inch, putting a face angle on of around 45 degrees, then leaning it sideways and back at around 45 degrees to give a cutting edge on the right hand side. In use, I hold the scorper at quite a high angle so the top edge leads, cutting first.

lynseysorefingers
02-02-2012, 10:16 AM
Thanks for the great advice, I have got a clear idea now how to go about setting this stone. I'll be taking my time, fingers crossed!



Hi linsey, the scorper will generally need shortening to be more comfortable in your hand. You heat only the part to be removed to dull red and immediately quench it. Then you put the scorper in a vice with the now blue part showing. Wearing eye protection,you hit it sideways with a hammer and the surplus should break off.

After that you grind it to a point again and tap on a handle.

However if your bezel is tapered it should be possible to do without any further bearer, provided you can keep the stone level. File down the edges so they stand only about a third of a millimetre above the girdle of the stone and neatly bevel the outside, so that only a knife edge has to be pushed over. As you work to set the stone, the eight corners will begin to pucker , but you can use a fine file gently on the raised bits as they occur. That way no gaps will show. Dennis.

lynseysorefingers
02-02-2012, 10:18 AM
Thanks Peter, great tips on shaping the scorper, I shall go forth and have a go. Hopefully it'll all come back to me.