SDL Atlas M258A-D Portable Thickness Gauge for Textile and Leather Testing
| Brand | SDL Atlas |
|---|---|
| Origin | USA |
| Manufacturer | Yes |
| Import Status | Imported |
| Model | M258A-D |
| Measurement Range | 10 mm × 0.01 mm (standard) |
| Anvil Diameter | 30 mm |
| Footprint Options | 50 mm, 100 mm, 200 mm probe span |
| Construction | Aerospace-grade aluminum alloy body |
Overview
The SDL Atlas M258A-D Portable Thickness Gauge is an engineered precision instrument designed specifically for non-destructive thickness measurement of flexible, compressible materials in textile, leather, nonwoven, paper, and foam manufacturing and quality control environments. It operates on the mechanical contact principle: a calibrated spring-loaded anvil applies a standardized, repeatable pressure (typically 0.1 N or 100 kPa per ISO 5084 and ASTM D1777) to the sample surface, while a high-resolution dial indicator or digital transducer measures the vertical displacement between the anvil and the fixed base plate. This method ensures traceable, operator-independent results compliant with international standards for compressible material thickness evaluation. Unlike optical or ultrasonic alternatives, the M258A-D delivers direct mechanical measurement unaffected by surface reflectivity, density gradients, or moisture content—critical for routine QC in wet-processing or finishing lines.
Key Features
- Lightweight aerospace-grade aluminum alloy housing (≤1.2 kg), enabling one-handed operation and field deployment without calibration drift from thermal expansion
- Interchangeable probe spans (50 mm, 100 mm, 200 mm) accommodate diverse specimen geometries—from narrow selvage strips to full-width fabric rolls—without requiring repositioning or cutting
- Standard 30 mm diameter flat anvil with hardened stainless steel face, ensuring uniform pressure distribution and minimizing localized indentation error per ISO 9073-2
- Dual-range capability: base configuration supports 0–10 mm at 0.01 mm resolution; optional M258A-D/30 variant extends range to 0–30 mm while retaining identical resolution and force profile
- Mechanically damped analog dial indicator (or optional digital encoder output) with zero-reset function and parallax-free glass lens for rapid visual verification under ambient lighting
- No battery or external power required—fully passive operation eliminates downtime, electromagnetic interference, and regulatory concerns related to electronic emissions
Sample Compatibility & Compliance
The M258A-D is validated for use across Class I and II textile substrates defined in AATCC TM195 and ISO 9073 series: woven and knitted fabrics (cotton, polyester, blends), suede and grain leather, technical nonwovens (spunbond, meltblown), corrugated board laminates, and low-density polyurethane foams. Its consistent 100 kPa applied pressure meets the minimum requirement for “low-force” thickness testing per ASTM D6193 and ISO 5084 Annex A. All configurations are supplied with NIST-traceable calibration certificate (as-tested at 0.5 mm, 2.0 mm, and 5.0 mm reference gauges), and comply with GLP documentation requirements for audit-ready records. The instrument satisfies clause 4.2.3 of ISO/IEC 17025:2017 regarding equipment suitability for intended use.
Software & Data Management
While the base M258A-D is analog-only, the optional digital transducer module interfaces via RS-232 or USB to SDL Atlas’ proprietary ThicknessIQ software (Windows 10/11 compatible). This platform enables automated data logging, statistical process control (SPC) charting (X̄-R, Cpk), batch-level reporting with customizable templates (PDF/CSV), and full 21 CFR Part 11 compliance—including electronic signatures, audit trails, and user access controls. Raw measurement timestamps are synchronized with system clock and embedded in metadata, supporting FDA-regulated textile medical device packaging validation (e.g., sterile barrier systems per ISO 11607-1).
Applications
- Pre- and post-finishing thickness verification to monitor shrinkage, calendering efficiency, or coating uniformity
- Leather tannery QC: split-layer consistency assessment prior to embossing or lamination
- Nonwoven filtration media R&D: correlating basis weight with compressed thickness under standard load
- Textile lab accreditation: fulfilling mandatory equipment criteria for ISO/IEC 17025 scope in physical testing
- In-line QA in garment manufacturing: rapid spot-checks of interlining, fusible web, or padding layers
- Academic research: generating reproducible thickness datasets for finite element modeling of fabric deformation behavior
FAQ
What standard test methods does the M258A-D support?
ASTM D1777, ISO 5084, ISO 9073-2, AATCC TM195, and GB/T 3820—all specifying 100 kPa nominal pressure and 30 mm anvil diameter.
Can it measure curved or irregular surfaces?
No—it requires flat, stable contact across the full anvil area; convex or highly textured samples must be conditioned or supported on rigid backing plates.
Is recalibration required after field transport?
No—its monolithic aluminum frame and frictionless pivot design eliminate zero-shift from vibration or orientation change; annual NIST-traceable verification is recommended.
How does it differ from ultrasonic thickness gauges?
Ultrasonic instruments require couplant and assume homogeneous sound velocity; the M258A-D measures actual compressed thickness under standardized load—essential for soft, porous, or multi-layered textiles.
Is operator training required for ISO-compliant use?
Yes—users must be trained in anvil cleaning protocol, sample conditioning (per ISO 139), and application of consistent downward force; SDL Atlas provides certified operator competency documentation.
