Adhesion Test on Paints by Tape Test

 Painting Inspection, Adhesion Test, QC Training, QC Course

  • X Cut Test (This Document)
  • Cross Cut Tape Test

Method A  – X Cut Tape Test

An X-Cut is made on the Dry Paint until the bare substrate , a pressure sensitive adhesion tape is applied over  the X cut and removed , the adhesion test is assessed between a scale of 0 to 5 .

Instruments used:

  1. Sharp Razor Blade / Knife (The cutting edge to be in a good condition,
  2. Cutting Guide -Any scale to guide the knife to make straight cut
  3. Brush to clean after cut
  4. Adhesion Tape- Semi Transparent of Width 25mm or 1 inch.
  5. Rubber Eraser – on end of the pencil
  6. Torch Light or Lamp

Test Procedure:

  • Select an clean and defect free area for test (note: do not carry out test in extreme humidity and temperature)
  • Make Two cross cuts of 40mm length with intersecting angle of 30 to 45 ° and the line should intersect in the middle, refer the image above ,
  • Use a torch light/ lamp to ensure that the cut has penetrated until the metal substrate, if not then make an x cut in different location.
  • Stich a 75mm long 1” pressure sensitive tape on the X cut with centre of the tape at the intersection, before taking the tape from the roll, make sure you remove & discard two complete laps of tape from the roll.
  • Slide your fingers over the tape to make sure of uniform adhesion and rub tape against the X cut using a pencil eraser.
  • Within 90 ± 30 Seconds of application pull of the tape by holding the free end rapidly pulling upon itself at an angle as close to 180° as possible.
  • Inspect the cut area for removal of coating and rate of adhesion in respect to the below criteria.

Results :

5 A- No Peeling or Removal

4 A – Trace peeling or removal along incisions or at the intersection.

3 A – Jaggered removal along inclusions upto 1.6mm on either side

2 A – Jaggered removal at most of the incisions upto 3.2mm on either side

1 A – Removal from most of the area of the X under the tape

0 A – Removal beyond the area of X .

Reference Standard for testing ASTM D3359, the details of Cross Cut Tape test – Method B will be discussed in next Blog, for updates please follow https://aqcinspection.com/news-events/

For more details on training and inspection of Painting please feel free to contact Advanced Quality Centre, https://aqcinspection.com/ , more trainings for QC Courses, NDT Courses, Welding Inspection Courses , and we stand out to be the best NDT Institute in South India.

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Location: Advanced Quality Centre,116-B, 5th St Ext, near Kalyan Jewellers, 5th Street Extension, Doctor's Colony, Gandhipuram, Tamil Nadu 641012, India

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