tws-902 visual inspection of finished metal parts[2] - telect visual... · 5.3.!painting!touch0up!...

Workmanship Standard Document number: TWS-902 Document name: Visual Inspection of Finished Metal Parts Revision: A6 Approval Date: 03/01/15

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1.0 PURPOSE

This document establishes minimum quality requirements for the cosmetic inspection of surface finishes and printing on material/parts.

2.0 SCOPE

This procedure includes all material used in Telect manufactured products that have a coated finished (i.e. painted or powder coated). This includes, but is not limited to: a. All material received from outside sources. b. Any material assembled, reworked, manufactured touched-up, etc., within Telect.

3.0 ISSUED BY/OWNER

Gary Kougl/Quality Assurance

4.0 REFERENCES ASTM Standard (D-3359-83) Telect Workmanship Standards on Materials and Color Specification 903


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5.0 DEFINITIONS

5.1. Cosmetic Flaws for Paint

5.1.1. Blister/Peeling/Flaking Enclosed raised spot resembling a blister. Any point where the coated material has separated from the base material

5.1.2. Bare Metal, Chips or Voids

Any marks on the base material that remains visible after coating. Areas of surface that have been broken, chipped, or missing paint.

5.1.3. Color Any change from the original color or unintended, inconsistent color that does not match the applicable standard as specified on the drawing.

5.1.4. Fish eye Cratering caused by organic contamination.


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5.1.5. Foreign Material Dirt, lint, or other particles being trapped in the paint.

5.2. Gloss, Uneven Any area of excessive or deficient gloss.

5.2.1. Orange Peel

An irregular or rough surface resembling the peel of an orange.

5.3. Painting Touch-up Defects hidden by use of touch-up paint, either spray or brush.

5.3.1. Paint Runs, Sags, or Excessive Paint Build-up

Areas where paint is applied so heavily that gravity causes it to flow downward.


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5.3.2. Scratches/Abrasions Wearing, grinding, or rubbing of painted surfaces.

5.4. Texture, Non-Uniform

Texture is not consistent from surface to surface or within the same surface or does not match the standard as specified on the drawing.

5.4.1. Burrs

Sharp or raised edge perpendicular to surface/edge

6.0 PROCEDURE

6.1 Classes of Finish

Unless otherwise specified by drawing, classes of finish are defined by how often/how visible the surface is in the finished product as seen by customer:

6.1.1 Class I Surfaces are frequently viewed. Typically front and top of product. 6.1.2 Class II Surfaces are occasionally viewed (typically the sides of the

product). 6.1.3 Class III Surfaces are rarely or never viewed. These are typically inside or

covered surfaces.

NOTE: For high gloss paints, all surfaces are to be treated as Class I.


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6.2 Rack Surface Classes

6.3 Cleanliness Parts shall be free of dirt, grease, and other contaminants. Dust caused by shipping material is acceptable if it can be blown off with air or wiped off.

6.4 Color The color is acceptable if the part and color standard are visually compatible, or if the difference in color is not readily apparent. The part is unacceptable if the color difference is easily detectable. Questionable conditions will be referred to Telect Quality Assurance for resolution.


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6.5 Texture Texture for powder coated surfaces is specified by the formulation indicated in Telect standard 903. Texture for wet painted surfaces is specified on the part’s fabrication drawing. The part is acceptable if the texture is visually compatible with the sample or standard texture and the texture is uniform throughout, or if the difference in texture is not readily apparent. The part is not acceptable if the texture difference is easy to detect or not uniform throughout one surface. Light over-spray on other than Class I surfaces is acceptable.

6.6 Coating Coverage

Coverage will be complete except as specifically noted on the specification or other Telect documentation, if not specified on the drawing. Location of the hanger marks to be contained within a hole or slot not to extend to the surface of the part. In areas where coverage is difficult due to the shape of the part, light coverage should be determined and approved prior to coating. Coatings are an integral feature of the finished material and, unless otherwise stated, feature dimensions are after coating. Areas such as wire management trays that may not be visible straight on (location used to house wire by customer) will require full coverage and some light over-spray will be accepted.

6.7 Adhesion/Coating

Paint shall not come off when rubbed with a dry cloth or with fingers. Paint shall not come off when subjected to an adhesion test. To perform an adhesion test of the paint, use the tester manufacturer’s instructions, or the following method:

a. Start the adhesion test by assembling scotch tape and a new/clean plastic bag.

b. Identify the area to be tested.

c. Place the part on the table. Do not clean the part prior to test.

d. Get the tape ready by placing tape on the part and rubbing in same direction three times. Make sure you have removed all the air bubbles.

e. Remove the tape by pulling rapidly from a 90-degree angle from the surface finish in question.

f. Place the tape sample in the plastic bag and seal.


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g. Evaluate the tape sample and, if you find any residue during this inspection and/or exposed bare metal on the part and/or parts in question, then reject the parts. There must be no evidence of finish coat removal on the tape.

6.8 Inspection Conditions (unless otherwise noted on Telect specifications)

Lighting: Daylight or cool white fluorescent lighting of approximately. Lighting should be diffused so shadows are not a factor. Viewing Distance: 18 to 24 inches. Viewing Plane: Parts shall not be manipulated to reflect a single light source in order to accentuate surface flaws. View without reflecting a single light source. Dwell Time: 8 to 10 seconds. Inspection Aids: No magnifying devices are permitted for visual inspection. Magnifying devices are permitted for determining the size of defects. Repetitive Inspection: A flaw that occurs repeatedly in the same surface location becomes more easily noticed. If this same cosmetic flaw was judged acceptable at the beginning of the lot inspection, it shall be acceptable at the end. Inspection for Bare Metal: Inspection for bare metal and paint voids should be performed with inspection flashlight to improve detectability. If other flaws are found with this increased lighting, they are to be ignored unless they are obvious without the increased light.

7.0 GENERAL

Note: The section list is not considered all-inclusive. Flaws or defects not noted below will be considered on a case-by-case basis depending on the class of surface finish and type of defect. Questionable areas should be referred to Telect Quality Assurance.


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Defect Class 1 Acceptance Criteria

Class 2 Acceptance Criteria

Class 3 Acceptance Criteria

Blister/Peeling/ Flaking

None allowed None allowed None allowed

Bare Metal, Chips or Voids

None allowed None allowed None allowed

Color See TWS-903 See TWS-903 See TWS-903 Fish eye N/A N/A N/A Foreign Material No more than 2

instances total, not to exceed .01” x .03” on any single surface in a 1 sq foot area.

No more than 4 instances total, not to exceed .03” x .06” on any single surface in a 1 sq foot area.


Gloss, Uneven No more than 4 instances not to exceed .02” x 1” on any single surface in 1 sq foot area.

No more than 8 instances not to exceed .06” x 1.5” on any single surface in 1 sq foot area.

No more than 3 instances not to exceed .13” x 2” on any single surface in 1 sq foot area.

Orange Peel None Allowed None Allowed Allowed Painting Touch-up Allowed Allowed Allowed Paint Runs, Sags, or Excessive Build-up

None Allowed None Allowed None Allowed

Scratches/Abrasions (bare metal not

exposed)


No more than 4 instances total, not to exceed .03” x .06” on any single surface in a 1 sq foot area

No more than 6 instances total, not to exceed .05” x .09” on any single surface in a 1 sq foot area

Texture,Non-Uniform None Allowed None Allowed Allowed Grind Marks Not visible at viewing

distance Not visible at viewing distance

Allowed

Tool Marks Visible but not to exceed .002” deep after paint. (Can’t be felt with fingernail)

Visible but not to exceed .005” deep after paint. (Felt easily with fingernail)

Allowed

Burrs / sharp edges None Allowed None Allowed None Allowed Pem Stud Head Requirements of Fab

Drawing Requirements of Fab Drawing

Requirements of Fab Drawing

Weld Porosity None Allowed None Allowed None Allowed Weld Spatter None Allowed None Allowed All slag and spatter to be

removed but the nuggets or rough surface left by the removal of the splatter may be present.

Spot Welds No ruptures to the surface. Size and diameter of witness marks shall not exceed 6 times the metal thickness.

Even, continuous, and smooth. Height of weld shall not exceed 30% of the width.

Pits may be present but not to exceed two (2) per ¼” of weld.


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Weld Workmanship This applies to the types of welding typically seen on production parts;; i.e.: TIG, MIG, spot, and electric arc. All welds are to exhibit good strength, workmanship, cleanliness, and meet applicable cosmetic requirements.

8.0 REVISION HISTORY

REV DATE REVISED

BY:

DESCRIPTION

00 10/31/01 Lynn Gustafson

Issued for review to Engineering, Purchasing, Quality.

01 12/7/01 Lynn Gustafson

New Workmanship standard. This procedure replaces QAP414. Major revisions to all sections.

02 4/14/04 Patricia Lee Change name of standard, redefine classifications, moved printing requirements to a new standard 905 and added new class “C1”

03 15-Mar-05 Jim Massey Changed ‘N/A’ to ‘None Allowed’ for Orange Peel condition in table 5.3.

04 31-Mar-05 Jim Massey Changed “Poor Painting Touch-up” to “Painting Touch-up”;; Removed photo of example of poor touch-up of paint.

05 22-Aug-05 Jim Massey Removed plating specifications that are covered in Std. 904;; other document cleanup & clarifications.

06 17-April-05 Brian Santora Clarified the criteria for burrs and added definitions

07 28-Oct-09 Pat Lee Update how to receive a controlling copy and removed reference on 20/20 eye site.

A3 07/21/10 Arlene Robbins

New format/Moved to PDM

A4 8/12/11 Pat Lee Updated standard chart was overlooked during new format/move.

A4.1 10/1/12 Pat Lee Added Telect Branding

A5 2/16/15 Gary Kougl Major revision to reflect outsourcing requirements;; Obsolete TWS 702.

A6 02-Mar-15 Jan Hutchins Added Surface Class specification for parts with a glossy finish


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9.0 Approvals

REV DATE APPROVED BY:

01 17 Aug. 07 Kelly Jones

02 18 Apr 08 Pat Patterson, Paul Knight, Pat Lee, Brian Santora

A4.1 01 Oct 12 Pat Lee – Formatting change.

A5 16 Feb 15 Gary Kougl

A6 02 Mar 15 Gary Kougl

tws-902 visual inspection of finished metal parts[2] - telect visual... · 5.3.!painting!touch0up!...

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