Tab

kerfmaster pin list · Definitions

rulingA decision by Aristide or Jordan. True because it was decided; it can be superseded, but it cannot be stale.

Content last changed 2026-08-28 — computed from the item itself, not typed.

Tab = a connection that is meant to be broken. Its entire purpose is that the material comes apart there easily, later in the manufacturing process. A tab is a production feature, not a design feature — it holds cut parts to the surrounding sheet (the skeleton) so they don’t drop or tip into the machine during the cut, and it gets broken out afterwards. Nothing about a tab is intended to survive into the finished part.

Tab width/thickness values are set at nest time and vary by material and thickness — see item 3a.

⚑ There are three holds, not two. A bridge is permanent and stays in the finished design (item 2b). A tab — this item — is sacrificial and holds the part to the surrounding sheet at nest time (item 3a). A slug-retention tab is sacrificial too, but sits on the waste side, holding an interior drop-out so it cannot fall through the bed (item 3b). Our spec originally used "tab" and "bridge" as synonyms — that was wrong.

Which of the three the code emits today: only the slug-retention tab. emit._slug_tab_width() sizes it and emit._leave_uncut() leaves the gap, on interior boundaries, at post time. The nest-time tab described in this item needs a position on a sheet; there is no nester, so nothing places one.

MetaCam’s word for this kind of sacrificial joint is wirejoint (Jordan, 2026-08-28).

src — Jordan, 2026-07-28 (terminology correction: tab = breaks off, bridge = stays).