DSS-M.01.05 — Hardware / Fastener Drag Line

Localized, directional linear line(s) or short runs created when hardware/fasteners/metal fittings (e.g., screw heads, rail/spider fittings, brackets) contact and move across the glass face, leaving a mechanical score. In raking light the line often exhibits bright “chip-flanks” / micro-chipping where depth increases; it persists after Non-Invasive Reveal (clean & dry) and is not a removable film. Use VIS terminology for micro-chipping / chip flank, worked surface, surface-catch (MSRT), and VIS viewing/lighting for appearance-based classification.

• Short, directional linear score emanating from or adjacent to hardware contact points (rails, spiders, standoffs, fasteners), sometimes with intermittent intensity where pressure varied.
• Sparkling edges in raking light from chip-flanks when depth is greater; may occur as single pass or clustered short runs.
• Persists after Non-Invasive Reveal (clean & dry). Inspect at VIS geometry (12 / 36 / 72 in; normal + oblique; raking).

Surface-catch class (MSRT):

• Commonly SC-2 (clear) for true metal-on-glass scores; SC-1 (slight) when shallow. Perform one light, non-marring pass only; MSRT supports classification, not acceptance. Prefer a polymer stylus if a functional coating may be present.

Reveal / lighting / geometry:

• Complete Non-Invasive Reveal before evaluation (clean & dry). Assess at 12 / 36 / 72 in, normal incidence + oblique sweep (~60°-120°) under raking light, per VIS. Record distances/angles in the photo frames.

Location / access:

• Confirm the cue is on the exposed face (not between panes). Use parallax when IGUs are present-fixed parallax indicates a between-pane condition; record surface numbering #1-#4 / laminate-internal on Forms: If between panes/inaccessible → CAT-5 by location.

Assign CAT by visibility convention and MSRT outcome at VIS viewing/lighting; apply the VIS three-part cueing (surface catch + edge/surface morphology + location/access):

• CAT-2 - Light: Narrow, clean-edged line(s) with SC-1, no pronounced chip-flanks; limited impact at standard view.
• CAT-3 - Moderate: SC-2 with minor chip-flanks; noticeable at standard distance.
• CAT-4 - Severe: SC-2 (clear-to-strong) with rough chip-flanks, possible pits/craters; distinctly visible at standard and wide-field views. (Classification is appearance-based; acceptance is handled separately in VIS §6.)

• CAT-2: ~0.2-1 μm (fine surface incision; minimal flank breakout).
• CAT-3: ~1-5 μm with incipient micro-chipping along flanks.
• CAT-4: ≥5 μm with rough chip-flank breakout; occasional pits/craters. (Depths are illustrative for cueing only; VIS classification/acceptance remains appearance-based.)

• vs. Straightedge/guide scoring (M.01.02): Guide scoring is ruler-straight over long runs; hardware drag lines are localized near contact points and often short-run.
• vs. Glass-on-glass tracks (M.01.03): Tracks present paired arcs/lines along a sweep path; hardware drag lines are single, local, originating at hardware.
• vs. Residue films/overspray (R-family): Residues change with Non-Invasive Reveal; mechanical scores persist. Apply VIS reveal + geometry.
• vs. Between-pane cues (A-family): Internal features show fixed parallax → CAT-5 by location.

• Photo set (VIS): 12 / 36 / 72 in, normal + oblique, include raking; add macro frames of the line showing edge morphology (chip-flanks if present) and no worked transition edge. Include at least one context frame that shows adjacency to hardware/fastener. Record reveal status, lighting, time, distance/angles.
• MSRT result: Record SC class (SC-1 / SC-2 as observed); one pass, non-marring; on suspected coated faces, prefer polymer stylus.
• Forms: Pane ID; surface numbering (#1-#4 / laminate-internal); worked surface Y/N; functional coating present on worked surface? (Y/N/Unknown); geometry checklist; attach photos-per VIS Appendix X3.

• Attempting to “feather” a drag line during inspection can create a worked region/transition edge, which VIS disallows at acceptance for CAT-0...CAT-4. Keep evaluation non-marring and appearance-only.

• M.01.05 Hardware/Fastener Drag Line - Localized linear line at #__ adjacent to hardware/fastener; MSRT = SC-1/SC-2; chip-flanks present/absent (record). Persists after Non-Invasive Reveal. Classified CAT-2/3/4 by visibility and flank severity per VIS. Photo set at 12/36/72 in (normal + oblique + raking), with a context frame showing the hardware origin; surface numbering and form fields recorded. Acceptance per VIS §6 (appearance-based).