DSS-R.03.01 — Suction Cup Rings (residue / pressure mark)

Suction cup rings are appearance changes on glass caused by vacuum lifter cups or manual suction tools during fabrication, transport, or install. They present as circular/oval rings, center pucks, or tri-/quad-lobe clusters reflecting multi-pad frames. Artifacts include transfer films (plasticizer, rubber, dust-print), pressure marks, or moisture halos; heavy dwell/heat can leave persistent veils. Classification is appearance-only per VIS (method-agnostic). Inspect after Non-Invasive Reveal under VIS lighting/geometry; record surface numbering and worked-surface status.

• Concentric ring (outer lip + inner puck), diameter commonly 80-400 mm depending on cup size; sometimes three-cup triangular or four-cup rectangular arrays.
• Soft, circular veil with darker edge ring (soil capture) and finger-like wipe arcs from hurried cleanups.
• Water-behavior contrast (beading) where hydrophobic mold-release or rubber plasticizer transferred.

Surface-catch class (MSRT)

• Typically SC-0 (film/pressure-only).
• SC-1 may appear where aged plasticizer or heat dwell induced slight micro-texture or converted film; SC-2 is uncommon-recheck classification if present.
• Perform one light, non-marring pass on a small revealed test patch (substrate), not over gummy islands. Polymer stylus if a functional coating is suspected. MSRT supports classification only.

Visual signature

• Perfect or near-perfect circles/ovals matching cup geometry; sometimes radial striations or vacuum port prints.
• Arrays align to spreader bar patterns (triangles/rectangles).
• No chip-flank sparkle (not mechanical scoring); no discrete fused pits (not hot-particle).

Viewing / lighting

• Evaluate clean & dry at 12 / 36 / 72 in, normal and oblique sweep (~60°-120°); raking reveals ring/lip edges, center puck, and wipe overlaps. Record distances/angles in-frame.

Location / access

• Record pane ID and surface numbering (#1-#4; laminate-internal). If fixed parallax shows the print within the IGU cavity (#2/#3), classify CAT-5 by location and refer.

Mechanism cue (context)

• Nearby glazing activities, spreader bars, vacuum lifter on site, crate marks, glass rack photos, or install sequencing.

Assign CAT by visibility at acceptance geometry and MSRT after a controlled reveal on a small area. Depth values are indicative-field measurement not required.

• CAT-1 (Benign / non-relief): Thin ring/veil; SC-0 after reveal; primarily angle/raking visible. Indicative relief: 0-10 μm (optical).
• CAT-2 (Light): Persistent circular veil with wetting contrast or slight SC-1 (aged plasticizer/heat dwell); limited standard-view impact. Indicative relief: ~10-40 μm.
• CAT-3 (Moderate): Multiple rings/arrays legible at standard distance (visual clutter), with patchy SC-1 in ring lips; suggests extensive handling exposure. Indicative relief: ~40-120 μm.
• Reclassify when: After true residue lift, any modeled micro-texture or SC>0 persists on substrate → consider Ch.06.02 hydrophobic coating mismatch halo or Ch.04.03 alkaline/degreaser burn if strong cleaners were used.
• CAT-5 (by condition/location): Between-pane by parallax, integrity issues, or coated-face loss on the surface to be worked → CAT-5.

CAT is appearance-based; acceptance is separate under VIS-A at 12/36/72 in. Do not abrade to “force” removal during classification.

• vs. Adhesive label/sticker ghost (R.01.05): Labels are smaller with die-cut corners; cup rings are larger round/oval with lip + puck geometry or multi-pad arrays.
• vs. Hydrophobic mismatch halo (Ch.06.02): Mismatch edges are irregular and field-wide; cup rings are precise circles matching pad size.
• vs. Silicone smear (R.01.01): Silicone tracks joints and shows corduroy; cup rings are isolated circles with wetting contrast.
• vs. Mineral rings (Ch.03.02): Mineral rings follow evaporation puddles and show concentric mineral deposits; cup rings have uniform interior with lip impression.
• vs. Paint overspray (R.02.01): Overspray is a speckled field without circular boundaries.

• Photo set (VIS): 12 / 36 / 72 in, normal + oblique; raking macros of ring lip, puck, wipe overlaps; context frames showing vacuum equipment or handling setup. Record distance/angle in-frame.
• MSRT result (substrate): After a small reveal test patch, perform one light, non-marring pass; record SC-class (SC-0/SC-1/SC-2).
• Forms: Pane ID; product family & surface numbering; worked surface Y/N; functional coating present on worked surface? (Y/N/Unknown); reveal status; lighting/time; geometry checklist; photos attached.
• Acceptance split: Post-restoration acceptance per VIS-A §6; classification ≠ acceptance. Coated-face appearance rules apply per VIS §6.2.e when the worked surface is a factory functional coating.

• R.03.01 Suction Cup Rings - Circular/oval ring + center puck on surface #___; post-reveal test patch shows [SC-0/SC-1]; visible at [12/36/72 in] under VIS geometry. Morphology: cup-size circle(s), array pattern, wetting contrast; no chip-flank sparkle, no discrete pits. Classification: CAT-[1/2/3] by visibility and SC-class; CAT-5 if between-pane or coating-side loss on the surface to be worked. Forms + photo set attached; acceptance per VIS-A §6.