Finetech Engineering

Dart Impact Tester

Overview

The Finetech Engineering Dart Impact Tester measures the impact resistance of plastic films, thin sheets, and laminates. If you manufacture polyethylene bags, stretch film, shrink film, BOPP packaging, or laminated pouches, the dart impact test tells you how much impact energy your film absorbs before it punctures. This value – the dart impact strength in grams – is one of the most commonly specified QC parameters on every film producer’s datasheet.

The test is simple: a hemispherical-headed dart is dropped from a fixed height onto a clamped film specimen. The dart weight is adjusted up or down using the Bruceton staircase method across 20–30 specimens until the weight that produces exactly 50% failures (F₅₀) is determined. This F₅₀ value, reported in grams, is the dart impact strength.

The Finetech falling dart impact tester ASTM D1709 India defines two methods – here is the ASTM D1709 Method A vs Method B difference: Method A uses a 38 mm dart dropped from 660 mm for commodity films; Method B uses a 51 mm dart from 1500 mm for tougher films. The Finetech tester supports both with interchangeable dart heads and adjustable drop height.

Tip: The falling dart impact testing machine plastic film India is designed for flexible films only. For rigid plastics (moulded bars), use the Izod & Charpy Impact Tester. For packages, use the Drop Tester. Different tests, different machines.

Method A vs Method B

Tip: When using the ASTM D1709 dart impact tester Method A Method B selection guide: start with Method A. If the lightest dart causes 100% failure, the film is too weak. If the heaviest dart causes 0% failure, switch to Method B.

The Bruceton Staircase Method

Feature

Method A

Method B

Drop Height

660 mm

1500 mm

Dart Head Diameter

38 mm

51 mm

Impact Velocity

~3.60 m/s

~5.42 m/s

Typical Films

LDPE, LLDPE, HDPE, PP (standard films)

Co-extruded, barrier, laminated, heavy-gauge films

Weight Increments

15–50 g steps

Larger steps

Most Common

Yes – for most PE/PP film QC

For tougher films where Method A darts are too light

The Bruceton staircase method works as follows:

  1. Drop dart on specimen. If it PASSES (no puncture) → increase weight. If it FAILS (punctures) → decrease weight.
  2. Repeat for 20–30 specimens. The test naturally oscillates around the true 50% failure point.
  3. Calculate F₅₀ from the weighted pass/fail data.
  4. Minimum 20 specimens required. Best practice: 25–30 for better precision.
Typical Dart Impact Values

Material

Typical F₅₀ (Method A)

LDPE film (bags, liners)

50–200 g

LLDPE film (stretch, heavy-duty)

100–400 g

HDPE film (carry bags)

50–150 g

BOPP film (snack packaging)

80–250 g

Co-extruded barrier film

200–800 g (Method B)

Laminated pouches

150–600 g

Compostable/bio-based film

20–120 g

Note: Values are indicative. Actual results depend on film thickness, resin grade, and processing conditions.

Specifications

Parameter

Specification

Product Name

Dart Impact Tester (Falling Dart Impact Testing Machine)

Method A Drop Height

660 ±10 mm

Method B Drop Height

1500 ±10 mm

Method A Dart Head

38 mm hemispherical, polished steel/aluminium

Method B Dart Head

51 mm hemispherical, polished steel/aluminium

Weight Increments

2, 5, 10, 15, 25, 50 g (standard set included)

Specimen Clamping

Pneumatic annular clamp, 125 mm exposure diameter

Specimen Size

Minimum 230 × 230 mm

Drop Mechanism

Electromagnetic release

Air Supply

4–6 bar compressed air

Power Supply

230V AC, single phase, 50 Hz

Standards

ASTM D1709, ISO 7765-1, IS 2508

Certification

ISO 9001:2015

Dart Impact vs Izod/Charpy vs Drop Test

Key rule: Dart impact for films. Izod/Charpy for rigid plastics. Drop tester for packages.

Feature

Dart Impact Tester

Izod/Charpy Impact Tester

Drop Tester

What It Tests

Flexible films/sheets

Rigid plastic bars

Complete packages

Result

F₅₀ in grams

J or kJ/m²

Pass/fail damage assessment

Standard

ASTM D1709, ISO 7765

ASTM D256, ISO 179

ASTM D5276, IS 7028

Applications
Industries Served
Why Choose the Finetech Dart Impact Tester?

Both Method A and B in one machine. Ideal as a dart impact tester flexible packaging India choice. Interchangeable darts and adjustable height cover all films from thin LDPE to tough barrier packaging.

Pneumatic specimen clamping. Uniform clamping eliminates wrinkles and slack – the #1 source of scatter in dart impact results.

Electromagnetic release. True free-fall, no spin, no push. Dart hits at exactly the calculated velocity every time.

Precision weight set included. Complete incremental weights (2–50 g) for accurate staircase progression.

Manufacturer, not trader – the best dart impact tester price India value comes direct from our Thane facility. Built at our Thane facility. Direct spare parts, calibration, and AMC.

Related Products

Product

Why Related

Izod & Charpy Impact Tester

Rigid plastic impact (different from dart for films)

UTM

Tensile testing of films per ASTM D882

Humidity Chamber

Conditioning specimens before testing

Rectangular Strip Cutter

Cutting film tensile specimens

Drop Tester

Package drop testing

Vibration Tester

Transport simulation for packaged films

Common Questions

Frequently Asked Questions

A machine that drops a weighted dart onto clamped plastic film. It determines the dart weight causing 50% failures (F₅₀), reported in grams. Standard method per ASTM D1709 and ISO 7765.

Minimum 20. Best practice 25–30. Cut from multiple positions across the film width for variability.

No. Dart impact is for flexible films. Use Izod/Charpy Impact Tester (ASTM D256) for rigid plastics.

Dart impact is sensitive to film thickness, resin molecular weight, blow-up ratio, and processing conditions. Always measure and record specimen thickness.

Yes. The Finetech ISO 7765 dart impact tester India meets ASTM D1709 and ISO 7765 requirements. Calibration certificates provided.