Sharpometer

One of the keys to efficient, easy mowing is a sharp blade acheived through peening and sharpening with whetstones. But how sharp is sharp? This year for the Somerset Scythe Festival there was talk of having a peening competition which, I’m glad to say, didn’t take place.  For me peening is something to be done carefully with awareness and not to be rushed.  I teach that peening is a relaxing activity that you undertake at the end of the day to take time to connect with and care for your scythe. Peter Vido calls it “my very enjoyable centering period of a summer’s day”.
So I was pleased that this was forgotten on the day but there was a certain tension in the air when Richard Brown unveiled his ‘Sharpometer’ based on a spring balance pulling a loop of cotton thread against the sharpened scythe blade. Since a scythe should be cutting with a slicing action I’m not sure how relevant the test was but it was a curiously fascinating device that we couldn’t tear ourselves away from and provided some good-natured competition on Saturday.
We discussed various improvements to the device and experiments that could be conducted to see the effects of mowing and honing in the field on the blade’s sharpness. It was also interesting to see how a brand-new blade had a very high (and therefore poor) score. I had been keeping a couple of my scythe blades to sharpen during the festival weekend so once they were finished I carefully sharpened and honed them with the whetstones before putting one on the sharpometer. After my first try, I realised there was just the merest burr still left on the edge so I polished this away and reduced the force required from 280g to 200g, with only Richard himself getting a lower ‘score’ with 180g (for comparison, a new stanley knife blade was measured at 160g).
With this kind of test we are peening the blade extremely thinly to offer least resistance to the thread. In real life, I peen the edge to suit the kind of vegetation I am cutting; a very fine edge for grasses and a steeper bevel angle for tougher work such as nettles, brambles or cereals. This is where it is useful to have separate scythe blades for different occasions.