An essential part of any carpentry tool kit are special carpenters pencils.
Different from normal pencils in that they are chunkier and have a much larger lead through the middle. Most people sharpen theirs with a knife but you can buy 12 with a special pencil sharpener for just £4.99 at Amazon.
They're essential for rough framing carpentry and roofing work because normal ones wear out too quickly (especially when working in the wet) on sawn timber and can easily snap. If you sharpen both ends, you don't have to stop what you're doing to sharpen a pencil when the lead snaps mid way through marking the work-piece.
For fine finish carpentry work though, the lead is too large and I use Staedtler 120-2 Noris HB Pencils.
It's really important for accurate setting out that I always keep my pencils really sharp. A thick line could be 2/3mm out if you cut the wrong side of it!
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