Dear Andrew and Jack, Your observations definitely resonate with me, especially the comment that...
> ... a relatively inexperienced stone cutter can use John's > technique and produce something that is at least acceptable > without years of practice. I have been incredibly lucky to have worked with a number of traditional stone workshops in the U.K., most particularly David Kindersley's Workshop in Cambridge where they still run an apprenticeship system. Even after 25 years of watching this place operate I continue to marvel at how people can be trained to do extraordinarily intricate things in stone. It is incredibly disciplined. On day one, new apprentices are simply asked to place a piece of drawing paper on a drawing board without creasing it. They are then given ten reasons why they got it wrong! One kink and its a failure. In stone, no mistakes are allowed, so they are taught early on that even perfection is only just good enough! Many tears get shed! > Drawing out the design directly on the stone means that > you have to do the whole thing by hand. Well yes and no. We are happy to use computers for producing a scale version of the design. The hour lines are calculated by computer as are constant declination curves and, indeed, anything mathematical. What happens next depends on the scale. If you have a big slab of stone wall, say 7m x 3m, then you are going to have a very unwieldy piece of paper if you insist on direct transfer! In these circumstances I mark the whole surface out in 1m squares using modern high-tech surveying kit (i.e. one of the more expensive total stations) and then fill in each square in turn, all by hand. In a particular case the summer solstice curve might be 6m long and will be represented by 100 points on a spreadsheet. I just accept that it takes a couple of hours to mark all the little Xs on the wall and then another hour to join these up satisfactorily with the aid of a piece of bendy wood. At its ends such a curve may deviate from a straight line by only a few mm in a couple of metres. It is important to get a continuous curve; the eye is very sensitive to short stretches of flatness. We then put tick marks on either side of this line and draw two other curves on on each side. Standard cutting techniques are then used to make a vee-cut. Often, constant declination curves are used as guidelines for lettering. These curves are again points on a spreadsheet which are transferred to the wall as Xs and the guidelines are then drawn through them. That's when people like Annika come along and, using the guidelines, simply draw letters by hand and get it right first time. Magic! > ... engraving the numbers would be particularly difficult for > me to do without a direct trace. I am totally sympathetic! I certainly couldn't do this either. I marvel at those who can but there seem to be plenty of them about! > Annika Larsson's step 7, "Cut. (or drill, or engrave or > whatever)" would be my downfall. Mine too! > Also, note that John developed the technique using sandstone. Yes, this IS noteworthy. Sandstone is pretty hellish! (though not as bad as granite) and EATS chisels! > I am now going to give it a try on limestone... Limestone has different problems. It is much kinder to chisels but it has fossils in it! Worse than that it may have huge holes where fossils used to be!! I remember the first time I worked on a limestone wall. I was shocked to find huge pits, maybe 5mm deep in places, where fossils had dropped out often EXACTLY where I wanted to place an X. I had had every intention to working to 1mm precision. Real life can be so hard!! This was the highest quality Bath stone and I didn't know how lucky I was. On a later dial, I had Portland stone and the wretched clients had specified that they wanted stone with `feature'. This is a euphemism for truly gigantic pits. Even Annika was a little perturbed when she found she could push a pencil 100mm into one of the holes! > I guess my point is that a relatively inexperienced stone cutter > can use John's technique and produce something that is at least > acceptable without years of practice. Indeed so and it is hard to see the apprenticeship system that supports these `years of practice' surviving indefinitely. Frank -
