Our Rigorous Quality Assurance System for Custom Acrylic Products

At Sunday Knight, premium consistent quality is the foundation of every custom acrylic (PMMA/Plexiglass) product we deliver to global clients across North America, Europe and beyond. Since our establishment in 2012, we have built a full-cycle, zero-compromise quality control system covering raw material screening, pre-production sample confirmation, multi-stage in-production inspection, final pre-shipment verification and complete after-sales quality guarantee. Every acrylic display stand, storage box, frame, decorative craft and custom fixture undergoes strict standardized checks to minimize defects and ensure full alignment with your requirements.

1. Strict Qualified Supplier & Raw Material Screening

Quality starts with raw material selection. We only cooperate with acrylic sheet suppliers holding complete SGS third-party test certifications, fully compliant with international regulatory standards including EU RoHS, REACH SVHC, POPs and US FDA food contact safety requirements.
Our SGS test reports (Report No. CANEC26001822601, issued Jan 23, 2026) fully verify that all our acrylic sheets contain non-detectable levels of restricted hazardous substances such as lead, mercury, cadmium, hexavalent chromium, PBBs and PBDEs. All raw panels pass independent lab testing on optical clarity, UV resistance, impact performance and batch color consistency.
We reject any raw material batches failing SGS compliance standards before they enter our production workshop, eliminating material-related quality risks at the source.

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2. Pre-Production Sample Confirmation: Lock Your Standard Before Mass Production

Before launching any bulk order, we manufacture a physical pre-production sample fully following your drawings, sketches or design briefs. Our engineering team executes CNC cutting, diamond polishing, UV printing, bending and assembly strictly as customized specifications.
Once finished, we send the finished sample to you for full visual, dimensional and functional confirmation. Every detail including size tolerance, edge finish, printing color, engraving alignment and assembly tightness is locked via your signed approval sample. All subsequent mass-produced goods will be inspected against this unified reference standard, eliminating inconsistent craftsmanship or design deviation.

3. 100% Full Incoming Material Inspection

(1). No acrylic sheet enters cutting processes without full incoming QC inspection. Our quality team inspects every single panel piece by piece, rather than random spot sampling, with digital precision measuring tools and dedicated light inspection stations to verify key indicators:
(2). Optical performance: Zero internal bubbles, inclusions, haze or cloudiness; consistent light transmittance
(3). Thickness tolerance controlled within ±0.1mm via digital calipers
(4). Surface integrity: No scratches, scuffs, peeling or defects on protective film
(5). Color uniformity: Batch color matching for colored acrylic sheets to avoid shade difference
(6). UV stability compliance validated against SGS technical data sheets
Any unqualified sheets are directly returned to our certified suppliers without being put into production, preventing wasted labor and flawed semi-finished products.

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4. Real-Time In-Process Inspection During Manufacturing

We embed inspection checkpoints across every production link: CNC cutting, thermal forming, diamond edge polishing, UV full-color printing and professional assembly lines. QC inspectors monitor semi-finished products continuously to capture and fix errors at the earliest stage:
(1). Cutting dimension verification against production drawings with ±0.1mm tolerance control
(2). Polishing edge inspection to eliminate chips, uneven gloss and foggy surfaces
(3). Precision gauge measurement of all bending angles for structural accuracy
(4). Printing alignment test before full batch printing to avoid offset patterns or blurred logos
(5). Intermediate assembly check for hardware fitting and bonding stability
If any defect is found during processing, the workpiece is immediately reworked or remade instead of flowing to the next procedure, stopping cumulative quality flaws in advance.

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5. Full Final Product Inspection & Pre-Shipment Batch Audit

Step 1: 100% Final Finished Goods Inspection

After assembly and before packaging, every single finished acrylic product is compared side-by-side with your approved sample under high-bright direct light for comprehensive full checks:

  • Surface screening for scratches, fingerprints, glue residues and cosmetic flaws
  • Complete recheck of printing color accuracy, engraving depth and adhesion strength
  • Joint bonding strength test and hardware matching inspection
  • Full dimensional re-measurement to match your approved sample specs
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All non-conforming items are fully scrapped and remade from scratch; we accept no “close enough” compromises.

Step 2: Pre-Shipment Batch Verification

Once all products are packed with custom foam inserts, corner protectors and protective film, our QC team conducts random batch pulls from sealed cartons to double-check product condition after packaging. We also cross-verify order quantity against your purchase order, validate shipping labels, commercial invoices and customs compliance documents.

If any packaging or product defect is found in sampling, the entire batch will be fully unpacked and re-inspected. No shipment leaves our factory until all cartons pass pre-shipment standards. Our drop-test qualified packaging further guarantees intact global delivery to US warehouses and EU distribution centers.

6. Complete After-Sales Quality Remediation Service

Although our multi-layer QC system keeps our long-term defect rate extremely low, we provide transparent, hassle-free solutions if defective goods arrive at your side:

  1. Submit claim within 7 days upon receipt: Send clear photos of outer cartons, inner packaging and defective products with your order number via our official email
  2. QC technical assessment within 48 hours: Our team cross-checks defects against your approved sample and full production inspection records to confirm manufacturing liability
  3. Free remanufacture & complimentary reshipping: All confirmed defective items will be remade strictly per your original sample standard with zero manufacturing and shipping cost for you; standard turnaround time for replacements is 10–15 working days
  4. Root cause optimization: Every quality complaint triggers internal process review. We trace the flaw back to its production stage, update inspection checklists and optimize workflows to prevent identical issues on future orders.

Our Authorized Quality Certifications

All our quality control procedures are backed by globally recognized third-party certifications, available for you to review upon order request:

  • SGS full material test reports covering raw acrylic composition, physical performance and hazard substance limits
  • RoHS, REACH SVHC, POPs compliance certificates for EU market sales
  • FDA certification confirming material safety for food-contact acrylic products
  • Complete Material Test Reports (MTR) with raw material batch traceability for bulk orders

We maintain full batch record traceability linked to your approved sample, supporting strict quality audit requirements for retail brands, premium merchants and industrial clients worldwide.

Why Our Full-Cycle QC Makes a Difference

Unlike many manufacturers relying on random spot checks, Sunday Knight implements 100% full inspection across raw materials, semi-finished goods and finished products for all order sizes, from small batches of 50 units to large bulk orders of 50,000 pieces. Our standardized multi-stage quality control, certified SGS raw materials and customer-centric sample confirmation process deliver consistent, matching results every shipment, earning long-term cooperative trust from premium brands across Europe and North America.