There are three words used to describe the relationship of a scythe blade to the snath and to the ground – the hafting angle, the lay and the neigung angle.
What is the Lay of a blade?
When a scythe is correctly set up, the back of the blade is on the ground and the cutting edge is about ¼ inch above the ground.
The lay is influenced by the curved shape of the blade from rib to edge and the relationship between the angle of the blade tang and the snath. This is one reason it is important to have a blade well matched to your snath.
Why is the lay important?
When mowing, the back of the blade is kept on the ground at all times. The lay of the blade lifts up the edge into a good mowing position.
If it is too low the edge runs very close to the ground. The blade mows very short and blunts quickly on grass roots, small stones etc. It can be temporarily useful to cut awkward grass stems that are laying down too much to be caught by a standard lay
If it is too high the edge slides over short grass and does not cut effectively. It can be temporarily useful to cut through tough stalks and tussocks.
Testing the lay of your blade
Hold the scythe in a relaxed position. When the back of the blade is on the ground the cutting edge should be about ¼ inch above the ground. This is just about enough to slip the end an Allan key under the edge.
Adjusting the lay
The lay can be temporarily altered by lifting or lowering the hands. Lifting the hands brings the blade edge away from the ground, lowering them brings it towards the ground. It’s hard to explain in words, get your scythe in your hands and have a go!
This allows you to temporarily adjust the lay of the blade to suit conditions whilst mowing.
If you consistently find that your blade blunts quickly or you have to lift your hands to get your blade to mow well, your lay may be too low. You can lift the lay using a wedge between the tang of the blade and the snath (see diagram, right)
It is also possible to adjust the lay by changing the angle of the tang itself. This involves heating the tang (to cherry red) and moving it, whilst being careful not to alter the temper of the metal or affect other angles such as the neigung. It is generally beyond the scope of most scythers.
The lay of the blade is also influenced by the relationship of the mower to the snath. Altering your posture,the positioning of the grips on your snath or your mowing style will also alter the lay. You may find you need a wedge for some mowing styles or some blades and not for others.