**Process Specification for Part Marking**

+-----------------------------------------------------------------------+
| **Engineering Directorate**                                           |
|                                                                       |
| **Structural Engineering Division**                                   |
|                                                                       |
| ### May 2007                                                          |
|                                                                       |
| ![](media/image1.emf)                                                 |
|                                                                       |
| National Aeronautics and                                              |
|                                                                       |
| Space Administration                                                  |
|                                                                       |
| **Lyndon B. Johnson Space Center**                                    |
|                                                                       |
| Houston, Texas                                                        |
+-----------------------------------------------------------------------+

**Process Specification for Part Marking**

+-----------------+----------------------------------+------+---------+
|                 |                                  |      |         |
+-----------------+----------------------------------+------+---------+
| **Prepared      | ####                             |      |         |
| by:**           |                                  |      |         |
+-----------------+----------------------------------+------+---------+
|                 | Julie A. Henkener                |      | Date    |
|                 |                                  |      |         |
|                 | Materials and Processes          |      |         |
|                 |                                  |      |         |
|                 | Branch/ES4                       |      |         |
+-----------------+----------------------------------+------+---------+

+-----------------+----------------------------------+------+---------+
| **Approved      | ####                             |      |         |
| by:**           |                                  |      |         |
+-----------------+----------------------------------+------+---------+
|                 | Brad Files, Chief                |      | Date    |
|                 |                                  |      |         |
|                 | Materials and Processes Branch   |      |         |
|                 | /ES4                             |      |         |
+-----------------+----------------------------------+------+---------+

  ----------- --------------------------------------------- ---------------
  REVISIONS                                                 

  VERSION     CHANGES                                       DATE

  \--         Original version                              5/15/97

  A           Various                                       7/6/97

  B           Various, including deletion of electric arc   1/30/98
              etching                                       

  C           Changed EM2 references to ES4, added white    3/26/02
              and red ink to Table 2, permits engraving     
              plastic by Table 1, removed MMPTD references, 
              added Sharpie marker for silicone rubber      
              parts                                         

  D           Expanded scope of PRC to include general,     3/30/04
              non-identification markings, such as arrows,  
              words or numbers, alignment marks, etc.       

  E           Added use of Sanford 13501 and 13401 markers  9/17/04
              for marking of Ground Support Equipment,      
              added 3.3.12                                  

  F           Corrected Sharpie marker part numbers. Added  4/4/05
              use of Sharpies for marking softgoods. Added  
              use of Sharpie markers for container          
              markings, provided markings are covered by    
              approved clear adhesive tape.                 

  G           Added references to SSP 57000 Appendix C and  2/16/06
              JSC 27260, removed reference to SC-D-0001.    
              Updated Table 2 of approved marking           
              materials.                                    

  H           Updated Table 2 to add Lord Corporation       4/24/07
              Chemglaze A074 with P-line pigments for EVA   
              applications, updated sections 3.2 and 3.3.6, 
              and 6.5.3 to include these new materials.     
              Removed specific references to ES4 in         
              sections 3.3 and 5.0.                         
  ----------- --------------------------------------------- ---------------

**1.0 [SCOPE]{.underline}**

This process specification establishes requirements for identification
marking and general marking of flight and non-flight hardware
manufactured by JSC or outside vendors.

# **2.0 APPLICABILITY**

This specification shall be applicable whenever marking for part
identification or general marking (such as arrows, words or numbers,
alignment markings, etc.) is invoked per Section 3.0, "Usage."

**3.0 [USAGE]{.underline}**

This section gives the requirements for the proper design usage of this
process specification. Additional requirements that apply specifically
to marking of Space Station payloads may be found in SSP 57000, Appendix
C.

The marking process shall be invoked by a process note on the
engineering drawing. The process note shall indicate the marking method
and reference this PRC. Character height and depth (when required) shall
follow, along with any additional requirements. Several example drawing
notes are shown in Figure 1 below:

+-----------------------------------------------------------------------+
| **PART NUMBER SHALL BE MARKED BY *{xxx method}* PER NASA/JSC          |
| PRC-9002. LOCATE APPROXIMATELY AS SHOWN.**                            |
|                                                                       |
| **PART NUMBER SHALL BE MARKED BY STEEL STAMP OR DIE PER NASA/JSC      |
| PRC-9002. CHARACTER HEIGHT SHALL BE 3/16 INCH. CHARACTER DEPTH SHALL  |
| BE 0.01 INCH. LOCATE APPROXIMATELY AS SHOWN.**                        |
|                                                                       |
| PART NUMBER SHALL BE MARKED BY RUBBER STAMPING USING 73X BLACK INK    |
| PER NASA/JSC PRC-9002. CHARACTER HEIGHT SHALL BE 3/16 INCH. LOCATE    |
| APPROXIMATELY AS SHOWN.                                               |
|                                                                       |
| **ENGRAVE PART WITH *{words, numbers, arrows, alignment marks, etc.}* |
| PER NASA/JSC PRC-9002. IMPRESSIONS SHALL BE FILLED WITH               |
| *{material}.***                                                       |
|                                                                       |
| **BAG AND TAG TO IDENTIFY PART NUMBER PER NASA/JSC PRC-9002.**        |
|                                                                       |
| **DECAL WILL BE USED FOR MARKING AND SHALL MEET THE DECAL             |
| REQUIREMENTS OF NASA/JSC PRC-9002.**                                  |
|                                                                       |
| **APPLY MARKING DECAL PER NASA/JSC PRC-9002.**                        |
+-----------------------------------------------------------------------+

Figure 1. Examples of process notes for identification marking.

**3.1 LOCATION AND LEGIBILITY OF MARKING**

The location of the marking shall be specified on the engineering
drawing. Location of the part shall be indicated on the drawing with a
box, which is flagged. The general configuration for a flag note to
specify marking location is shown in Figure 2 below:

Figure 2. Sketch of the configuration for a flag note designating
marking location.

Specific information on the format of part and serial numbers and how to
write the flag note to indicate marking placement may be found in
Section 3.4. Factors that should be considered when specifying a
location include:

-   whether damage could occur to a critical surface due to stamping or
    etching

-   whether a detailed part number should be visible at the next
    assembly, top assembly, or installation level

-   whether total or partial obliteration of the marking could be caused
    by the assembly process

-   whether verification of an assembly will depend upon visibility of
    component part numbers

Assembly markings shall be visible under conditions of normal vision in
daylight, or in equivalent illumination. Parts and assemblies having
unsuitable or insufficient surfaces (i.e., small springs, glass or
plastic optical elements, etc.) or drawings which specify "No Marking
Permitted" shall be identified by Container Marking (see Sections 3.3.9
and 3.4.7). NHB 5300.4 (1D-2), paragraph 1D502, shall be complied with
in all instances.

**3.2 SIZE AND COLOR OF MARKING**

Marking size shall be specified on the engineering drawing. The choice
of character height shall be in increments of 1/32 inch, from 1/16 to
1/2 inch inclusive, with 1/8 inch being the default if no size is
specified. Character size in accordance with the point value system is
acceptable, with 12-point being preferred. The size of characters shall
be proportioned to the area available for marking. The size of markings
shall be uniform from part to part within the practical limits of
readability. An example of the character size callout is as follows:

  -----------------------------------------------------------------------
  **CHARACTER HEIGHT SHALL BE 3/16 INCH.**

  -----------------------------------------------------------------------

Character depth is applicable only for certain marking methods. Unless
called out by the process note, the manufacturing organization may
select a character depth, as long as it is consistent within a marking
and does not exceed the maximum depth allowed for the specific marking
process. An example of the character depth callout is as follows:

  -----------------------------------------------------------------------
  **CHARACTER DEPTH SHALL BE 0.01 INCH.**

  -----------------------------------------------------------------------

In terms of color, the preferred color for rubber stamping, stenciling
or filled impressions shall be black or white, as appropriate for
maximum contrast. Markings of other colors having contrast to the part
are also acceptable and the product name and color of the ink or paint
shall be specified on the engineering drawing in the parts list.
Acceptable products and their colors/pigments are listed in Table 2.

**3.3 MARKING METHOD**

The marking method chosen shall be selected to preclude damage or
degradation of part quality. The default sequences for marking during
part finishing are shown in Table 1 below:

**Table 1. Default sequences for marking during part finishing.**

  -------------------- ------------- ---------- ----------- ----------- ------------- ----------- -------------
                       **CRES**      **Alum**   **Brass**   **Steel**   **Foil        **Painted   **Plastic**
                                                                        Labels**      Brass or    
                                                                                      CRES**      

  **Diamond Drag**     before        before     after all   n/a         n/a           after all   n/a
                       passivation   anodize or finishing                             finishing   
                                     chemfilm                                                     

  **Steel Stamp or     before        before     after all   before      before        n/a         n/a
  Die**                passivation   anodize or finishing   paint or    application               
                                     chemfilm               phosphate                             

  **Electro-chemical   before        before     after all   n/a         n/a           n/a         n/a
  Etch**               passivation   anodize or finishing                                         
                                     chemfilm                                                     

  **Electric Vibrating before        after      after all   before      n/a           n/a         n/a
  Pencil**             passivation   anodize or finishing   phosphate                             
                                     chemfilm               or plating                            

  **Engraving**        before        before     after all   n/a         n/a           n/a         before or
                       passivation   anodize or finishing                                         after all
                                     chemfilm                                                     surface
                                                                                                  finishing

  **Rubber Stamping**  after         after      after all   after all   n/a           after all   after all
                       passivation   anodize or finishing   finishing                 finishing   surface
                       or paint      chemfilm                                                     finishing

  **Stenciling**       after         after      after all   after all   n/a           after all   after all
                       passivation   anodize or finishing   finishing                 finishing   surface
                       or paint      chemfilm                                                     finishing

  **Insert**           n/a           n/a        n/a         n/a         n/a           n/a         during layup
  -------------------- ------------- ---------- ----------- ----------- ------------- ----------- -------------

  ------------- ------------- ---------- ----------- ----------- -------- ----------- -----------
  **Decal or    after         after      after all   after all   n/a      after all   after all
  Nameplate**   passivation   anodize or finishing   finishing            finishing   surface
                or paint      chemfilm                                                finishing

  ------------- ------------- ---------- ----------- ----------- -------- ----------- -----------

**3.3.1 Diamond Drag (Impression Marking)**

Diamond Drag markings are formed by a pantograph system using an
industrial diamond stylus. Diamond drag marking is unsatisfactory
(illegible) where a thick finish (e.g., hard anodize) would subsequently
be applied. This method shall not be specified when it will be harmful
to the finished part. Character size may range from 0.040 to 3/16 inch,
with a depth necessary to obtain reasonable legibility, but not to
exceed 0.015 inch.

3.3.2 Steel Stamp Or Die (Impression Marking)

These markings are formed by pressing or stamping by hand or machine
with character shaped steel stamps or dies.

Steel stamps shall normally consist of characters 1/16 to 3/16 inch
high. The depth of the impression shall be no greater than is necessary
to obtain reasonable legibility, but shall not exceed 0.015 inch.

Impression stamping (steel stamp or die) of parts shall not be used on
the following items without prior approval of the cognizant materials
engineer:

a.  Ferrous parts heat-treated above 160 ksi ultimate tensile strength
    and metallic parts work-hardened above one-fourth harder than the
    normal annealed condition.

b.  All metallic materials 0.040 inch thick or less.

c.  All magnesium alloys except castings provided with a raised pad for
    marking purposes.

d.  Surfaces contoured to a dimension.

e.  Areas where subsequent metal removal will obliterate the marking.

f.  On a surface less than 1/2 inch from the edge of a part or less than
    3/8 inch from the edge of a finished hole or recess, or less than
    1/4 inch from the tangent lines of bends or fillets.

g.  Less than 1/4 inch from weld beads.

h.  Metal tank skins.

i.  Pressure tubing and push-pull control tubing.

j.  Pressure vessels.

**3.3.3 Hot Impression Stamping**

Hot impression stamping is intended for use where a permanent type of
marking is required on insulation sleeving. The markings shall be in
proportion to the size of the space to which they are applied.

**3.3.4 Electochemical Etching**

Electrochemical etching shall be used for permanent marking of bare
metallic or conductive surfaces when preferred over rubber stamping, or
where impression stamping is unsuitable. Electrochemical etching is used
where a quick, permanent, and non-injurious method is required on an
area which will not be covered with paint. This method shall not be
applied to dynamic bearing surfaces or used for instruction markings.
The location of the marking shall be selected to preclude the accidental
trapping of the electrolytic solution in crevices. The minimum material
thickness which shall be etched by this method is 0.010 inch.

**3.3.5 Electric Vibrating Pencil**

Marking by this method is not recommended for use on flight hardware.
This method is subject to the same restrictions as Steel Stamp or Die
marking (see Section 3.3.2). Marking shall not cause disfigurement on
the opposite surface of thin materials.

**3.3.6 Engraving**

The minimum thickness of the base materials to be engraved shall be
0.030 in. for all metals (except nameplates) and for all molded or sheet
plastics. However, for multi-layer or reinforced laminates, the minimum
thickness shall be 0.060 in. Engraving is subject to the same
restrictions (a through j) noted in Section 3.3.2, paragraph three.

If desired, impressions can be filled with a permanent coating in a
contrasting color from Table 2. This is specified by addition of one of
the following process notes:

+-----------------------------------------------------------------------+
| **IMPRESSIONS SHALL BE FILLED WITH** *{material}*                     |
|                                                                       |
| or                                                                    |
+-----------------------------------------------------------------------+
| **PRIME WITH** *{approved primer in Table 2}* **AND FILL IMPRESSIONS  |
| WITH** *{material}*                                                   |
+-----------------------------------------------------------------------+

depending on whether or not primer is required. Primer must be used for
filled flight hardware engravings, but is not necessary for Ground
Support Hardware. Both the primer (if used) and the filling material
shall be added to the drawing parts list. Super Koropon Primer (both
primer base and curing solution) is manufactured by Courtaulds
Aerospace, and drawings should reference the following information:

Courtaulds Aerospace

Glendale, CA 91203

CAGE Code 83574

Additional details regarding materials requirements for filled
engravings are given in Section 6.5.3.

**3.3.7 Rubber Stamping**

Rubber stamping shall be applied on painted, plastic, ceramic, anodized,
and other nonmetallic surfaces where impression stamping and
electrochemical etching are not suitable. Identification markings should
not be placed on teflon-coated surfaces without prior approval by the
cognizant materials engineer.

**3.3.8 Stencil Marking**

Stencil marking is used where the volume of marking is large. Terminal
boards of epoxy laminate may be marked by stenciling. The location of
the marking shall in no way interfere with the electrical functions of
the board. Identification markings should not be placed on teflon-coated
surfaces without prior approval by the cognizant materials engineer.

**3.3.9 Container (Bag and Tag) Marking**

Container marking may be used for small electrical and electronic parts,
attaching hardware, parts having dielectric properties, and parts and
assemblies which cannot be marked by other means or where individual
tagging is not practical. Parts and assemblies shall be identified
according to the requirements of section 6.5.8. Parts and assemblies in
this category that require serialization shall be placed with only one
item per container.

**3.3.10 Insert Markings**

As an optional method of marking transparent or translucent laminate
parts (i.e., polyester/glass fabric), an ink-stamped insert may be used.
A piece of glass fabric is stamped with the required information using
black marking ink. The marked piece is inserted between the outer two
plies of laminate during lay-up. The insert shall be placed near an edge
of the part as specified on the engineering drawing.

**3.3.11 Decals or Nameplates**

Decals or nameplates of various types may be used for identification
marking of hardware. The decal detail drawing shall indicate that the
decal will be utilized for marking and meets the applicable requirements
of this specification. The assembly drawing shall also indicate that the
decal application process meets the requirements of this specification.

Decals shall conform to MIL-STD-1472 (*Human Engineering Design Criteria
for Military Systems, Equipment and Facilities)*. Decals that are known
to emit corrosive vapor shall not be used in closed packages. Protective
coatings (i.e., lacquer) shall not be applied on decals unless chemical
compatibility has been established. All decal materials used for flight
hardware shall be in accordance with Section 5.0 of this specification.
The minimum character size on decals shall be 8 point. Certified ink
ball-point pen markings on decals are acceptable. JSC 27260 contains a
list of approved decals.

3.3.12 Use of Sharpie Markers

Sharpie markers are easy and convenient to use, but do not always
constitute a form of permanent marking, since the ink can be removed by
the application of solvents. However, they may be used to mark silicone
rubber parts that are not easily markable by alternate methods. Also,
the use of Sharpie markers for marking softgoods is permissible. The
appropriate part numbers for these applications are Sanford 35001 to
35004 for extra fine point markers of various colors. Fine point (30001
to 30004) markers are acceptable as well. In addition, specialized
Sharpie markers that are called Trace Element Certified (TEC) may be
used to mark aluminum and other metallic components that are for Ground
Support Equipment (GSE) only. These are not normal Sharpie markers,
since they contain a special ink. Before use, it must be verified that
the part number of the marker is either Sanford 13501 or Sanford 13401.
Marking should be done after all metal finishing has been completed.

**3.4 FORMAT FOR PART AND SERIAL NUMBERS**

Each part or assembly shall be marked, except those parts which are
permanently attached to other parts or assemblies (i.e., welding,
brazing, or soldering). Parts which do not require marking may be marked
for production convenience providing the methods of marking conform to
the requirements of this specification. Any item marked per this
specification shall include, as a minimum, the complete part number.

  ----------------------- ----------------------- -----------------------
                          **P/N SEZ               
                          39100999-001**          

  ----------------------- ----------------------- -----------------------

Figure 3. Example of identification marking consisting of a complete
part number.

Additional information to be included in the marking, such as the serial
number, may be indicated on the engineering drawing in the drawing flag
note. The information may be located below the part number or adjacent
to it. Figure 4 shows an example of how to specifically indicate that
the information should be placed adjacent to the part number, and Figure
5 shows an example of how to mark the additional information below the
part number.

Figure 4. Example of symbol to be used if information is to be located
adjacent to the part number.

Figure 5. Example of symbol to be used if information is to be located
beneath the part number.

In addition, placement of the marking may be at the discretion of the
marking technician. An example of the notation to be used in this
instance is shown in Figure 6.

Figure 6. Example of symbol to be used when placement is at the
discretion of the marking technician.

**3.4.1 Serial Numbers**

Batch or lot controlled parts do not require serial numbers if a
mandatory traceable batch lot system is used. All other parts or
assemblies shall have serial numbers as specified in JPG 8500.4. A
general example of the format of part and serial numbers is indicated in
Figures 4 and 5.

**3.4.2 Assemblies**

Assemblies not identified with a nameplate that includes nomenclature of
the part, shall have the word "assembly" or "assy" placed immediately
below the part number and serial number, as shown in Figure 7 below:

+-----------------------+-----------------------+-----------------------+
|                       | **P/N SEZ             |                       |
|                       | 39100999-001**        |                       |
|                       |                       |                       |
|                       | **S/N 1005**          |                       |
|                       |                       |                       |
|                       | **ASSY**              |                       |
+-----------------------+-----------------------+-----------------------+

Figure 7. Example of identification markings on hardware that is part of
an assembly.

**3.4.3 Equipment**

Equipment (i.e., valves, pumps, electronic equipment, etc.) shall be
marked with the following minimum information, in the order noted:
Nomenclature, Part Number, Serial Number, Contract Number, Manufacturer,
NASA-JSC-USA.

**3.4.4 Explosive Devices**

Explosive devices shall be marked with the following minimum
information: Nomenclature, Contractor, Manufacturer, Part Number, Lot
Number, Serial Number, Date of Manufacture, ICC Classification.

**3.4.5 Non-Flight Hardware**

Hardware or equipment which is not suitable for use in flight and which
could be accidentally substituted for flight articles shall be marked as
either "Class III Not For Flight" or "Class II Controlled Equipment," as
shown in Figures 8 and 9.

+---------+-------------------+---------+-------------------+---------+
|         | **P/N SEZ         |         | **P/N SEZ         |         |
|         | 39100999-001**    |         | 39100999-001**    |         |
|         |                   |         |                   |         |
|         | **S/N 1005**      |         | **S/N 1005**      |         |
|         |                   |         |                   |         |
|         | **Class III Not   |         | **Class II        |         |
|         | for Flight**      |         | Controlled        |         |
|         |                   |         | Equipment**       |         |
+---------+-------------------+---------+-------------------+---------+

Figures 8 and 9. Examples of the two options for marking the non-flight
hardware described in 3.5.5.

**3.4.6 Rejected Flight Hardware**

Flight equipment which is not acceptable for flight shall be striped
with a compatible contrasting paint, red being the most desirable color
unless contrast is not sufficient. Equipment too small to be so marked
shall be tagged with an appropriate red tag which is conspicuously
marked: "Class II Controlled Equipment" or "Class III Not For Flight"
per JSCM 5312 *(Safety, Reliability and Quality Assurance Manual).*

**3.4.7 Container (Bag and Tag) Markings**

Container markings for non-serialized parts, per Section 3.3.9, shall
include the quantity of parts in the container. For example:

+-----------------------+-----------------------+-----------------------+
|                       | **P/N SEZ             |                       |
|                       | 39100999-001**        |                       |
|                       |                       |                       |
|                       | **Quantity 5**        |                       |
+-----------------------+-----------------------+-----------------------+

Figure 10. Example of container markings for non-serialized parts.

Container marking for serialized parts or assemblies, per Section 3.3.9,
shall include only one item per container and, as a minimum the format
shall include the part number and serial number, as shown in Figure 11
below:

+-----------------------+-----------------------+-----------------------+
|                       | **P/N SEZ             |                       |
|                       | 39100999-001**        |                       |
|                       |                       |                       |
|                       | **S/N 1005**          |                       |
+-----------------------+-----------------------+-----------------------+

Figure 11. Example of container markings

**4.0 [REFERENCES]{.underline}**

The following references were used to develop this process
specification:

SOP-007.1 *Preparation and Revision of Process Specifications*

JSC-SPEC-M1 *Specification*, *Marking and Identification*

The following documents are called out as an extension of the
requirements given in this specification and should be used in the
current version, unless a revision is specified:

Federal Spec TT-T-266 *Thinner, Dope, and Lacquer (Cellulose- Nitrate)*

JPG 8500.4 *Engineering Drawing System Manual*

JSC 27260 *Decal Process Document and Catalog*

JSCM 5312 *Safety, Reliability and Quality Assurance Manual*

MIL-STD-1472 Military Specification, *Human Engineering Design*

> *Criteria for Military Systems, Equipment and Facilities*

NHB 5300.4 (1D-2) *Safety, Reliability, Maintainability, and Quality
Provis-ions for the Space Station Program*

SSP 57000, Appendix C Instructions for Labels and Decals, *Pressurized
Pay-loads Interface Requirements Document*

**5.0 [MATERIAL REQUIREMENTS]{.underline}**

Materials other than those listed in Table 2 must be approved by the
cognizant materials engineer prior to use for marking flight hardware.
All materials used for the marking process shall be included on the
engineering drawing, in the drawing parts list.

**Table 2. Approved materials for hardware marking.**

\*Not to be used to mark silicone rubber material

  ----------------------- ----------------------- -----------------------
  Manufacturer            Manufacturer's          Marking Process
                          Designation             

  Independent Ink, Inc.   73X black marking ink\* Rubber stamping and
                                                  stenciling

  Independent Ink, Inc.   73X white marking ink\* Rubber stamping and
                                                  stenciling

  Independent Ink, Inc.   73X orange marking      Rubber stamping and
                          ink\*                   stenciling

  Independent Ink, Inc.   73X red marking ink\*   Rubber stamping and
                                                  stenciling
  ----------------------- ----------------------- -----------------------

+-----------------------+-----------------------+-----------------------+
| Sanford               | Sharpie Extra Fine    | Marking and           |
|                       | Point 35001 to 35004  | stenciling, silicone  |
|                       |                       | parts and softgoods   |
+-----------------------+-----------------------+-----------------------+
| Sanford               | Sharpie Fine Point    | Marking and           |
|                       | 30001 to 30004        | stenciling, silicone  |
|                       |                       | parts and softgoods   |
+-----------------------+-----------------------+-----------------------+
| Sanford               | TEC Marker Broad      | For use on Ground     |
|                       | Point 13501           | Support Equipment     |
|                       |                       | only                  |
+-----------------------+-----------------------+-----------------------+
| Sanford               | TEC Marker Fine Point | For use on Ground     |
|                       | 13401                 | Support Equipment     |
|                       |                       | only                  |
+-----------------------+-----------------------+-----------------------+
| Wornow Process Paint  | CAT-L-INC             | Silk Screening        |
+-----------------------+-----------------------+-----------------------+
| Wornow Process Paint  | White Screen Ink      | Silk Screening        |
|                       | 50-100                |                       |
+-----------------------+-----------------------+-----------------------+
| Dexter Corporation    | Hysol Epoxy M-O-N     | Filled Impressions    |
|                       | with catalyst         |                       |
+-----------------------+-----------------------+-----------------------+
| Nusil Technologies    | CV-1144-1 (white RTV) | Filled Impressions    |
|                       | with SP-120 silicone  |                       |
|                       | primer                |                       |
+-----------------------+-----------------------+-----------------------+
| Nusil Technologies    | CV-1146-2 (black)     | Filled Impressions    |
|                       | with                  |                       |
|                       |                       |                       |
|                       | SP-120 silicone       |                       |
|                       | primer                |                       |
+-----------------------+-----------------------+-----------------------+
| Lord Corporation      | Chemglaze A276 (white | Filled Impressions    |
|                       | polyurethane)         |                       |
+-----------------------+-----------------------+-----------------------+
| Lord Corporation      | Chemglaze A382        | Filled Impressions    |
|                       |                       |                       |
|                       | (black polyurethane)  |                       |
+-----------------------+-----------------------+-----------------------+
| Lord Corporation      | Aeroglaze Z306        | Filled Impressions    |
|                       |                       |                       |
|                       | (black polyurethane,  |                       |
|                       | low out-gassing)      |                       |
+-----------------------+-----------------------+-----------------------+
| Lord Corporation      | Aeroglaze Z307 (black | Filled Impressions    |
|                       | polyurethane,         |                       |
|                       | conductive)           |                       |
+-----------------------+-----------------------+-----------------------+
| Lord Corporation      | Aeroglaze Z202 (white | Filled Impressions    |
|                       | polyurethane)         |                       |
+-----------------------+-----------------------+-----------------------+
| Lord Corporation      | Chemglaze A074 (clear | Filled Impressions -- |
|                       | polyurethane)         | EVA applications only |
+-----------------------+-----------------------+-----------------------+
| Lord Corporation      | Chemglaze P550 (Red   | Filled Impressions -- |
|                       | Color Concentrate)    | EVA applications only |
+-----------------------+-----------------------+-----------------------+
| Lord Corporation      | Chemglaze P750 (Blue  | Filled Impressions -- |
|                       | Color Concentrate)    | EVA applications only |
+-----------------------+-----------------------+-----------------------+
| Lord Corporation      | Chemglaze P850        | Filled Impressions -- |
|                       | (Yellow Color         | EVA applications only |
|                       | Concentrate)          |                       |
+-----------------------+-----------------------+-----------------------+
| Lord Corporation      | Chemglaze 9986        | Filled Impressions    |
|                       | (Catalyst)            |                       |
+-----------------------+-----------------------+-----------------------+
| Courtaulds Aerospace  | Super Koropon Primer, | Filled Impressions    |
|                       | 515-700               |                       |
+-----------------------+-----------------------+-----------------------+
| Kingsley Machine Co.  | KT-26 marking foil    | Hot Impression        |
|                       |                       | Stamping              |
+-----------------------+-----------------------+-----------------------+
| Mystic Tape Inc.      | Tape, number 7300     | Decals                |
+-----------------------+-----------------------+-----------------------+
| Metal Cal Company     | A1 foil labels PS-9   | Decals                |
|                       | heat activated        |                       |
|                       | adhesive              |                       |
+-----------------------+-----------------------+-----------------------+
| Horizons Imaging      | Metalphoto ID plates  | Decals                |
| Systems Group         |                       |                       |
+-----------------------+-----------------------+-----------------------+
| 3M                    | Scotch Brand tape     | Decals                |
|                       | #465                  |                       |
+-----------------------+-----------------------+-----------------------+
| 3M                    | Scotch Brand tape     | Decals                |
|                       | #468 MP permanent     |                       |
|                       | adhesive              |                       |
+-----------------------+-----------------------+-----------------------+
| 3M                    | Scotchcast #221 (5095 | Decals                |
|                       | adhesive)             |                       |
+-----------------------+-----------------------+-----------------------+
| 3M                    | Scotchcast #8         | Decals                |
|                       | encapsulant           |                       |
+-----------------------+-----------------------+-----------------------+
| 3M                    | Scotchcast 220        | Decals                |
+-----------------------+-----------------------+-----------------------+

  ------------------------ ---------------------------- -----------------
                                                        

  ------------------------ ---------------------------- -----------------

**6.0 [PROCESS REQUIREMENTS]{.underline}**

**6.1 WORK INSTRUCTIONS**

Written work instructions shall be generated for implementing this
process specification. These work instructions shall contain sufficient
detail to ensure that the manufacturing process produces consistent,
repeatable products that comply with this specification.

**6.2 CLEANING PRIOR TO MARKING**

The affected area of parts shall be thoroughly cleaned prior to marking,
with non-injurious solvent such as a liquid detergent or lacquer thinner
(Federal Spec TT-T-266). Precaution shall be taken to avoid the use of
solvents, which may adversely affect the material being cleaned.

**6.3 COLOR OF MARKING**

The color of markings shall be uniform from part to part within the
practical limits of readability and contrast with background color.
Certified ball-point pen markings may be utilized when all other marking
methods are impractical.

**6.4 CHARACTER HEIGHT**

Character height shall be measured from the center-line to center-line
of each character, as shown below in Figure 12:

Figure 12. Example of center-line measure of character height.

**6.5 APPLICATION OF MARKING**

In applying markings, care must be taken to ensure that the markings do
no damage or in any way downgrade the quality of the articles. The
markings shall be applied to clean surfaces after final surface
finishing, unless otherwise noted by this specification or the
engineering drawing. The surface finish, if applied over the markings,
shall not impair the legibility of the marking.

**6.5.1 Diamond Drag (Impression Marking)**

Diamond Drag markings are formed by a pantograph system using an
industrial diamond stylus. Diamond drag markings shall be applied prior
to final finish unless otherwise specified on the drawing. This method
shall not be deleterious to the finished part. The markings shall have a
depth necessary to obtain reasonable legibility, but shall not exceed
0.015 inch.

**6.5.2 Steel Stamp or Die (Impression Marking)**

Impressions shall not cause detrimental or induced stresses, impair the
proper function of the surfaces to be marked, or cause cracking,
crushing, distortion, delamination or visible marks on the reverse side
of the surface being marked. Metal nameplates, tags, and similar items
shall be exempted from the latter requirement and shall be stamped
before attachment to the part. Steel stamp or die marking shall be
applied prior to final surface finishing. Stamping shall be performed in
a manner which will leave uniform impression. Characters shall have all
sharp corners rounded to a radius of 0.005 inch, +.005 /-.000 inch on
1/16 to 3/32 inch characters, and a radius of .010 inch, +.005/-.000
inch on 1/8 to 3/16 inch characters.

**6.5.3 Filled Impressions**

If specified on the engineering drawing, impressions shall be filled
with a permanent coating selected from Table 2. For non-flight and other
ground support hardware, it is not necessary to use a
corrosion-resistant primer, such as Super Koropon, prior to filling with
a polyurethane paint or other coating. However, for flight hardware, the
Super Koropon primer shall be applied to the substrate that has first
been finished according to the requirements listed in Table 1 prior to
application of material for filling. If the Chemglaze A074 clear
polyurethane paint is used, it shall be mixed with the P550, P750 or
P850 pigments specified in Table 2, according to the manufacturer's
instructions. At this time, Chemglaze A074 with the P-line pigments is
approved for extravehicular activity (EVA) applications only, since
toxicity data has not yet been generated.

**6.5.4 Hot Impression Stamping**

The stamping shall be applied by the Kingsley Stamping Machine, Model
No. KW-7, or NASA approved equivalent, in accordance with the
manufacturer's recommendations. When marking sleeving, the tools and
fixtures of the marking machine shall be properly matched with the
contour of the surface to be marked. The markings shall be in proportion
to the size of the space to which they are applied. Impression stamped
markings may also be applied to thermoplastic surfaces (nameplates) by
use of heated dies. Maximum temperature of dies used to mark acrylic
plastics is 300^o^F.

**6.5.5 Electrochemical Etching**

The etchings, and the area around them, shall be thoroughly cleaned to
remove corrosive chemicals after marking. Electrochemical etching shall
be accomplished by use of Electro Chem Etch Co. "Producer" power unit,
or NASA approved equivalent, in accordance with the manufacturer's
recommendations.

**6.5.6 Engraving**

Engraving shall be applied to metal surfaces prior to finishing unless
otherwise noted on the engineering drawing.

Characters shall be engraved to a depth necessary to obtain the required
width of mark. The depth of groove shall be 0.003 minimum, and shall not
exceed 50 percent of the base material thickness.

**6.5.7 Stencil Marking**

The manufacturer's procedure for applying on a teflon-coated item must
be known in order to determine the method required to stencil the part
identification with teflon enamel. The enamel shall be fused to the base
surface with the proper process determined by the manufacturer.

Ink markings shall be applied according to the manufacturer's
recommendations. The drying time recommended shall be the minimum drying
time before handling and/or determining the permanency of the marking.
Permanent ink markings shall be impervious to solvents and ultrasonic
cleaning processes. The use of ball-point pen markings is acceptable on
decals and metallic foil tape. Care should be taken to make markings
legible. Application of certified ink ball-point pen markings shall
comply with Section 5.0 of this process specification.

**6.5.8 Container (Bag and Tag) Markings**

Parts and assemblies shall be identified by affixing a completed JSC
Form 1106 to, or by rubber stamping the container, bag, envelope, etc.
It is very convenient to use Sharpies to mark containers, such as
ziplock bags, but the numbers are easily removed by contact such as
rubbing or the incidental application of solvents. Thus, it is only
permissible to use Sharpie markers for container marking, provided the
markings are covered by an approved clear adhesive tape, such as 3M 800
for protection. Parts and assemblies that require serialization shall be
placed one to a container.

**6.5.9 Insert Markings**

As an optional method of marking transparent or translucent laminate
parts (i.e., polyester glass fabric), an ink stamped insert may be used.
A piece of glass fabric is stamped with the required information using
black marking ink. The marked piece is inserted between the outer two
plies of laminate during lay-up. The insert shall be placed near an edge
of the part as specified on the engineering drawing.

**6.5.10 Metal Nameplates**

Metal nameplates shall be completed with all available information
before attaching to the article to be identified. Nameplates shall be
marked by any of the methods specified in this process specification.
Certified ball-point pen marking of metal foil is acceptable. Nameplates
of an aluminum foil type shall be legibly marked by impression stamping,
typing and/or permanent ink marking with non-serif characters, 8-point
minimum in size, of the Gothic or Futura style. Masking with heavy,
clean paper, or with tape compatible with surfaces being marked shall be
employed to provide for extending the clear acrylic coating beyond the
nameplate edge a maximum of 1/4 inch. The manufacturer's recommended
drying time shall be the minimum drying time before inspecting the
nameplate.

**6.5.11 Decals**

Decals shall be legibly marked by typing with non-serif characters,
8-point minimum in size, of the Gothic or Futura style. Certified
ball-point pen markings on decals are acceptable. Decals attached to the
surface shall be legible and not exhibit any tears, bubbles, wrinkles,
or other defects, which may affect identification and/or adhesion.

**7.0 [PROCESS VERIFICATION]{.underline}**

All markings applied in accordance with this specification shall be
visually inspected for legibility, definition, and uniformity. The
location of the marking shall meet the requirements on the engineering
drawing. Failure to meet any of the requirements specified herein shall
be cause for rejection and must be documented in accordance with
NASA/JSC SR&QA manual procedures (JSCM 5312).

**8.0 [TRAINING AND CERTIFICATION OF PERSONNEL]{.underline}**

No formal training is required for marking technicians. However,
personnel shall be certified by their supervision to perform work to
this process specification.

9.  **[DEFINITIONS]{.underline}**

None.