Transparent PMMA Inspection Fixture | 50mm Clear Acrylic Go/No-Go Gauge

Tagged: PMMA CNC Acrylic CNC CNC Milling

We successfully delivered a precision machined transparent PMMA inspection fixture for a quality control department in the automotive components industry. Machined from optically clear PMMA (acrylic), this inspection gauge measures approximately 50mm in length and features two extended mounting ears with precision fixation holes. The transparent body allows operators to visually verify component alignment and seating against reference surfaces during manual inspection processes.

Project Overview

Project Name	Transparent PMMA Inspection Fixture
Material	PMMA (Acrylic / Polymethyl Methacrylate)
Material Color	Optically Clear / Water White
Process	CNC Milling + Precision Drilling
Key Feature	Transparent body, extended mounting ears, precision holes
Overall Dimensions	Approx. 50mm (L) × as designed (W) × as designed (T)
Mounting Hole Diameter	As specified (precision drilled)
Mounting Hole Position Tolerance	±0.05mm
Inspection Surface Flatness	≤ 0.05mm
Light Transmittance	> 92% (visible spectrum)
Surface Finish	Optically clear, machined surfaces smooth
Application	Manual inspection / Component seating verification / Go/no-go gauging

Key Technical Highlights

Transparent Inspection Design: Clear PMMA material enables operators to visually confirm proper component seating and alignment against reference surfaces, eliminating guesswork in manual inspection.
Extended Mounting Ears: Two precision-machined ears with fixation holes allow secure mounting to inspection benches or fixtures while keeping the inspection area clear and accessible.
Precision Reference Surfaces: CNC machined flatness ≤0.05mm ensures accurate go/no-go gauging and consistent inspection results across multiple parts.
Optical Clarity for Visual Gauging: Water-clear transparency allows backlighting or visual comparison against master components, ideal for contour matching and gap inspection.
Scratch-Resistant Surface: PMMA maintains optical clarity even with repeated handling in production inspection environments.
Burr-Free Edge Finishing: All machined edges smoothed for safe handling during manual inspection operations.

Material Properties

Property	Value
Light Transmittance	> 92% (at 3mm thickness)
Refractive Index	1.49
Density	1.19 g/cm³
Tensile Strength	65 – 75 MPa
Impact Strength (Izod)	15 – 20 J/m
Continuous Operating Temperature	-30°C to +70°C
Water Absorption	0.3 – 0.4% (24 hours)

Quality Verification

100% dimensional inspection performed using digital calipers and optical comparator. Critical inspection surfaces verified for flatness. Mounting hole positions measured against CAD model. Visual inspection ensures optical clarity and freedom from machining marks. First-article inspection report provided with each batch.

Industry Applications

✓ Automotive component inspection
✓ Manual go/no-go gauging
✓ Contour matching verification
✓ Seating and gap inspection
✓ Optical comparison against master parts
✓ Production line quality control
✓ Incoming goods inspection
✓ Assembly verification fixtures