Stop in for a cup of coffee

It's a small envelope with another envelope inside containing two 'nickers' for cutting across the grain for dados.
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Stanley also called them 'spurs'.

On the Combination plane there is one on the main section, and another on the sliding section which is easier to see.
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In 1918 they got small teeth to create a rack rather than rely on friction to keep them from retracting. But of course back then they continued to offer replacement parts for the older models....

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