On the surface, this is a playful tribute to a woodworking tool, the thin-bladed coping saw used for cutting curves. But the pun in the last line changes everything. The poem builds a list of "because" reasons, each describing a feature of the saw: it bends, it has many tiny teeth, it cuts on the pull, it favors circles over straight lines. Then comes the payoff: "somehow / it copes."
Read that way, the saw becomes a model for getting through life. Flexibility, willingness to follow curves, and the knack for "impromptu reconstitution" (putting things back together on the fly) are also traits of people who handle trouble well. The odd detail that the saw "encompasses / so much empty space" suggests that gaps and absences are part of what makes it work.
The speaker sounds fond and gently amused, admiring the tool without fuss. The mood is light and warm, with a quiet note of wisdom underneath. The word "somehow" admits that coping never quite has a tidy explanation.