Accurate piercing

**Didi** · 25-10-2011, 01:20 PM

I have a little half sphere that I want to pierce out to leave a lattice pattern. What do people use to mark the metal where they want to cut? on flat sheets I use a sticker that I've drawn on but it won't work on the sphere. I've tried drawing direct on the metal but it just smudges as I handle the piece. I guess this question should really be directed to James who, in my view, is the acknowleged master of piercing. Any help would be much appreciated though.
Thanks in advance

**Goldsmith** · 25-10-2011, 01:50 PM

Hi Didi,
Here is my method of marking a lattice pattern for piercing on a half sphere. I use a pair of dividers like these; http://www.cooksongold.com/Jewellery...prcode-999-571 and some simple geometry methods. I first find the centre point of the dome and punch a mark in the centre. Then I divide the circumference of the into equal sections as to the size of lattice I want. Then I use the dividers to mark arcs from the centre point to the marks around the circumference. You can practice this method with a compass and a circle on paper. As with most methods this is easier for me to show than explain.
I used this method to mark out the lattice work on this egg, the top half or the egg is a sphere.
James

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**Goldsmith** · 25-10-2011, 01:57 PM

Didi,
If what I have said is not useful, then let me see what design you wish to mark out and on what size of sphere and I will let you know in more detail how I would do it. I have a few other tricks that I use when marking out piercing patterns on dome shapes.
James

**Didi** · 25-10-2011, 03:22 PM

Hi James
The sphere is 19.5mm diameter and i would like to have an even number of points at the edge. 6 or eight would be good. I think if I try for more the solid bits will just be too thin and although I am not too bad at piercing I'm really still a beginner
Many thanks
Didi

**Didi** · 25-10-2011, 03:27 PM

Sorry James, that was not the most helpful reply. I am wanting to do the same pattern as you have done on the egg.
Didi

**Goldsmith** · 25-10-2011, 05:33 PM

Didi,
Your half sphere is smaller than I imagined, I think if I was making such a small thing I would try piercing the lattice pattern requirements on a flat disc and then use a doming punch in a dome block to shape the pierced disc carefully into the required half sphere.
Another method that I use to draw patterns onto shaped surfaces is to first polish the shape, then degrease it and paint the polished surface with white poster paint, let it dry and then draw my design on the painted surface, if you make mistakes with the design just add fresh paint and start again. When I am satisfied with the design I gently draw over the pencil design on paint with a scriber point and when done, wash of the paint and the scribed lines will show up well against the polished surface.
good luck, James

**Didi** · 25-10-2011, 06:21 PM

James
I did think of piercing it first but then I worried about the pattern distorting. The paint idea is sheer genius, I happen to have some vinyl emulsion handy from decorating. I think the vinyl emulsion will just peel off when Im done, also I can probably use and eraser on the pencil. Thank you so much. I will let you know how I get on
Didi

**Didi** · 07-08-2012, 02:36 PM

Hi there. Thought I ought to let you know how I got on. Here's the finished piece. The case was pierced ( using James' excellent method), I attached a tiny hinge (much swearing), threaded a glass bead so the whole sphere would rotate and made a bail. The chain is viking knit and the clasp is a lentil clasp which I made using the same technique as the sphere. Many, many thanks James, your work is inspiring.
Didi