Fastener holes & ties — sizing, opposition, visibility

kerfmaster pin list · The spec — what we build to

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 True because it was decided; it can be superseded, but it cannot be stale.

Content last changed 2026-08-09 — computed from the item itself, not typed.

Generalized from the teaching file (Aristide rulings, 2026-08-07/08):

• Tie-hole size: the smallest centre-pierceable hole that still passes the strap — max(strap diagonal, the material's min_pierce_hole from the tables). For the 2.5 mm zip tie that is max(0.110, 0.125) = 1/8".
• Pairs OPPOSE across the shared cut line: a candidate is a point on the edge; the two holes sit either side of it along the edge's NORMAL, each sunk hole-radius + clearance into its own metal, so the tie pulls square across the joint — never oblique. Web ladder: 0.20 standard, 0.15 fallback, 0.11 last resort; square at the smaller web beats oblique at the larger.
• Minimum web around any fastener hole: 0.20" (slots: see [[stud-slot-rules]]).
• Visibility rule: a hole in a finished face is acceptable only where it is never seen. Where the visible face cannot take holes, use a STRAP: the tie passes through two holes in sacrificial/hidden material and across the piece, and the finished part takes no hole at all.

Claims follow measurement (added 2026-08-09): the web stated on any sheet is the MEASURED MINIMUM of the final geometry, never the design floor. A hole that measures under the stated floor is reported as a breach or fixed — quoting the floor beside geometry that misses it is a defect.