Friday 22 October 2010

Plugs & Feathers

Following on from yesterday's post about the simple things which drive us mad because they do not work, here's an example of a some simple things which work so beautifully and efficiently, that they are an absolute joy. I don't use them very often, but when I do, I am filled with renewed admiration for them, and an almost overwhelming sense of achievement, attained with very little effort. They are 'Plugs and Feathers'.

Remember that huge, stone head I carved a while ago? Well the above photos are the 'before and after' shots of how I trimmed the excess off the one-ton block, in about 15 minutes.

If you have a massive block of stone which is too hard to hand-saw, then you need a set of plugs and feathers. I bought my (one inch diameter) set about 30 years ago, and paid a lot of money for them, but they have paid for themselves many times over, both in monetary terms and aesthetics, even though they are rarely used.

Mode de Emploi (excuse my French): Simply decide on where you want the clean break of the stone to be, and score a line to mark it. Drill a series of holes (slightly under one inch diameter) at regular intervals on three sides of the block, on the line. Insert the three-part plugs and feathers, with the wedge-shaped part expanding in the direction of either side of the line. Gently tap the tops of the 'feathers' (an old English term for a wedge is a 'feather') uniformly on all three sides. Each feather will take about three sets of taps before the desired result, and the result is shocking.

GOLDEN RULE: Make sure that you do not have your toes beneath the part of the block which is going to fall without any more warning than a slight change of ring-tone, and make sure that you are standing to the side, so that when the piece falls and rolls onto it's side, both of your legs are not broken, leaving you trapped and calling for help which may never come.

That's it. I do not know the amount of pressure that these little, iron plugs exert, but it is measured in tons, not pounds. Get cracking.

7 comments:

  1. Amazing Tom. You wouldn't think that such simple tools would make such a clean cut on that huge piece of stone. I meant to comment yesterday re the things that do not work that makes you mad. Lately I've been wondering why I have eyes and ears that do not work. That I find maddening.

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  2. Fabulous! You're right, simple tools that do what it says on the box are a delight. I've just come back from buying myself a new small 115mm angle grinder, and the wretched thing didn't work properly. It had a wobble in the blade. It took me an hour to find that they'd assembled the bloody thing wrongly back in China. Drives you NUTS.

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  3. Brilliant...simple, small, 100% effective...I love that.

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  4. Love hearing about your the tools of your trade,I would be interested to know more about your stone carving.

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  5. Sorry can't write properly again today!

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  6. The precision of those plugs and feathers is quite mind boggling, Tom, especially when you take into consideration the weight of the stone and the pressure exerted. Not a nice experience to mis-calculate have flat toes and broken limbs I shouldn't think!!

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  7. Thanks all. Golden Rule number 2: Never skimp on quality for tools. A Chinese disc cutter may look as good as a German one, but be 1/10th of the price. Put a really expensive diamond blade on it, and that microscopic wobble on the bearings mean the difference between a nice clean cut, and £10,000 worth of damage to an antique piece of marble. It can also mean a poorly brazed tooth flying off the 3000 RPM blade, and blinding you or worse. I have had friends who have had to have operations to remove a diamond tooth section from between the joint of their thumb, which had gone in like a bullet.

    You CANNOT beat a good quality, continuous-rim, 10 inch, diamond blade. It will cut through anything, last for years and cost about £80. Diamonds are a girl's best friend.

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