Fences, stops and chip collection for the planers. The rebate depth stop is the one that turns a planer into a joinery tool — set the depth and the machine cuts a rebate to it repeatably instead of by eye. Parallel fences keep the cut square to the face. The chamfer adaptor holds a set angle for easing an edge. Chip bags and extraction adapters matter more here than on most tools: a planer produces volume quickly, and unextracted shavings jam under the fence and spoil the cut.
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