The cracking board
A student's Practical is a 1.5 × 1.0 m acrylic painting on 3 mm untempered masonite, built up over five weeks in eleven poured and brushed layers. Two weeks before the due date the surface has begun to crack along the board's grain in the lower third, and paint is lifting at two corners. The student sealed the board with a single coat of PVA diluted 1:1, applied only to the front face. The task sheet requires the submitted work, a 300-word statement of technical decisions and six process photographs. The student has four photographs, all taken after the final layer. The student wants to start again on stretched canvas, which would leave eight school days of drying time before marking.
1. Diagnose the likely cause of the cracking and lifting, and explain why adding more medium on top is not a repair.
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The pattern is diagnostic rather than mysterious: cracking that follows the grain and lifting at the corners points to differential movement between the support and the film.
Masonite is absorbent and moves with ambient moisture. Sealing only the front with one dilute coat leaves the back free to take up moisture and swell, while the front carries a relatively stiff, non-permeable acrylic film. The board expands under a film that cannot, and the film fails where the board is most restrained and most dimensionally active - along the grain and at the corners. If any layers were medium-rich and applied over leaner ones, that adds a second, compounding cause.
Adding more medium on top is the wrong move for two reasons. It increases film thickness and stiffness, raising the stress on an already-failing bond. It also seals the failure in place, so the crack continues under a new skin and the repair becomes invisible exactly where information is needed. The correct interventions are to consolidate locally, address the unsealed reverse, and control drying - or to accept the cracking deliberately as content, which is a legitimate decision only if it is stated and consistent with the work's idea.
2. The student has eight school days. Give a decision - repair in place, restart on canvas, or something else - with reasoning, and state what evidence you would require before signing off.
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Repair in place, with a 72-hour decision point, on the grounds of drying budget and irreversibility of loss.
The original surface took five weeks and eleven layers. Eight days cannot reproduce that, because each pour needs time to cure before the next; a restart produces a thinner, less resolved painting and discards five weeks of investigation. The cracking is also arguably congruent with the work's theme, so the defect sits inside the concept rather than outside it - which changes the cost of keeping it.
Plan: lay the board flat, weight it, consolidate the lifting corners with a flexible adhesive introduced under the film, seal the reverse to slow moisture uptake, then dry slowly under weight. After 72 hours, reassess. If stable, continue with thin applications only. If the lifting has spread, restart - but restart small, at 1.0 × 0.7 m, so the drying schedule fits.
Evidence required before sign-off: dated photographs of the reverse before and after sealing, a note of the intervention and its reasoning, a test patch of the adhesive on an offcut, and a dated photograph of the cracks in raking light. Sign-off requires a decision that is documented, not merely a decision.
3. The process photographs are inadequate. Explain what the missing evidence costs in assessment terms, and how the record could be reconstructed honestly in the time available.
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Four photographs, all taken after the final layer, document an outcome, not a process. The Practical descriptor rewards technical resolution and documented decision-making, so the student is currently losing credit for the half of the work that cannot be seen in the finished object - the choices about layers, drying, adhesion and revision.
Reconstruction, honestly:
- Photograph the current state properly: raking light across the cracks, the reverse face, the corner lifting, and the consolidation in progress.
- Capture one test patch and one offcut, showing the adhesive and the sealed reverse.
- Include non-photographic traces: material receipts and order dates, the layer-notation sketch, a scanned colour test sheet.
- Caption every image with a date, and label the sequence as recorded at the point of failure. Do not caption them as if they were taken during construction.
Honesty is not just ethical here, it is strategic: an assessor can distinguish a staged sequence from a real one by lighting, tidiness and continuity, and a discovered fabrication undermines the whole submission. Six well-chosen images at genuine decision points beat thirty near-identical ones.