1、MIL-C-85070 (ASG) 23 DECEMBER “- 1963 MILITARY SPECIFICATION COATING, WASH PRIMER (PRETRE-) FOR METALS, APPLICATION OF (FOR mRONAWICAL USE) This specification has:been approved by the Department of %the Air Force and by the Bureau of Naval Weapons! 1. SCOPE 1.1 This specification provides instructio
2、ns for the application of wash primer pretreatment coating compound, Specification MIL-C-8514, prior to appli- cation of a primer. 2. APPLICABLE DOCUMENTS 2.1 The following documents of the issue in effect on date of invitation for bids or request for proposal, form a part of this specification to t
3、he extent specified herein: Federal O-D-306 Diacetone Alcohol, Technical (Acetone-Free) TT-B-846 Butyl Alcohol, Normal (Butanol) (for use in TT-1-735 Isopropyl Alcohol, Technical TT-M-26g Methyl Isobutyl Ketone (for use in Organic Coatings) TT-T-266 Thinner, Dope and Lacquer (Cellulose Nitrate) Orga
4、nic Coatings) Military MIL-A-6091 Alcohol, Ethyl, Specially Denatured, Aircraft MIL-F-7179. Finishes and Coatings, General Specification for MIL-P-7962 Primer Coating, Cellulose-Nitrate Modified Alkyd Protection of Aircraft and Aircraft Parts Type, Corrosion-Inhibiting, Fast-Drying (for Spray Applic
5、ation Over Pretreatment Coating) “4-8514 Coating Compound, Metal Pretreatment, Resin Acid MIL-P-8585 Primer Coating, Zinc Chromate, Low-Moisture- Sensitivity Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-P-15328 - STD. NO. 14l Methods of Inspec
6、tion, Sampling, and Testing (Copies of specifications, standards, drawings, and publications required by suppliers in aonnection with specific procurement functions should be obtained from the procuring activity or as directed by the contracting officer.) 3. MATERIAL AND EQUIP“ 3.1 Wash primer coati
7、ng.- The wash primer coating shall conform to Specifi- cation MIL-C-g514. Unless otherwise .specified, this material shall be used on clean ( . base metal surfaces prior to the application of mandatory paint finishing -systems. Poor adhesion will result if the surface is not absolutely clean. 3.2 Ea
8、uipnlent .- Pressure pot liners and mixing equipment shall be made of stainless steel to resist the chemical attack of the phosphoric acid in the wash primer coating material. Detailed procedures for the use of equipment will be found in Specification MIL-F-18264. Cleanliness must be exercised, sinc
9、e wash primer coating,mce polymerized, becomes difficult to dissolve. 4. PROCEDURF, 4.1 Surface preparation.- Wash primer coating shall be applied over metal surfaces which have been surface treated and cleaned as specified in Specification MIL-F-18264. A brief summary of general cleaning and surfac
10、e preparation procedures is included in the appendix for general guidance. The appendix does not replace or supersede the more extensive and detailed requirements as specified in Specifications MIL-F-7179, MIL-F-18264, and related documents. The latter documents shall be employed by contractors and
11、overhaul activities. t 4.2 Method of kine;.- 4.2.1 Pot life.- For application temperatures below 90 F, the primer must be used within 4hours and for application temperatures above 90 F, within 2 hours of mixing. 4.2.1.1 Application after these time limits may result in poor adhesion, even though the
12、re is no apparent visible change in the material. 2 .- F- I ,“ Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-4.2.2 Wna procedtlre - aenera1.- The following mixing procedure shall be used: Thoroughly shake, using a “Red Devil“ or approved equivalent
13、 shaker, both the acid and resin components prior to mixing to reincorporate any settled portion, Reincorporation of hard cake in aged resin oomponent may be faalitated by pourlng off the top liquid into a clean container, brealring up the hard c.- Application of the wash primer coating may be accom
14、- plished by roller coating to a dry film thickness of 0.3 to 0.4 mil. 4.3.4 Swabbing.- Application of the wash primer coating by swabbing may be employed for touchup if this means of application is most expedient. 4.4 prying time.- Although the wash primer coating dries to handle wthfi a few minute
15、s, it shall be allowed to dry not less than 60 minutes nor more than 4 hours before application of topcoating paint systems, slnce premature application of primer may impair the adhesion of the finish system. Topcoats should not be applied until the wash primer coating is capable of resisting remova
16、l with the fingernail. I 4.4.1 Nustment for local conditi=.- No definite drying time limits are available which incorporate all variable processing conditions. The actual minimum drying periods must be predetermined by tests based on local temperatures and humidity conditions encountered during the
17、projected painting operations. Best intercoat adhesion will generally be obtained after 1- to 2-hour drying period, since intercoat adhesion begins to degrade slowly on aging indoors, and markedly when exposed to the sun. However, the minimum drying period specified (see 4.4) may be reduced to 45 mi
18、nutes if a complete finish system confollning to Specifica- tion MIL-F-18264 or other applicable specification applied on large test panels under production conditions (see 5.2) results in satisfactory adhesion when tested in accordance with the anchorage test (tape test), Method 6301 of Federal Tes
19、t Method Standard No. 14l. 5 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL4-8507B(ASG) 4.4.2 Local investigations.- The following suggestions are made as starting - ( points for the local investigations or to determine the necessary drging time
20、s or thinning modificationsr (a) If painting is done in a heated hangar (above !Oo F) and ethanol- is the only diluent used, the minimum drying period of 60 minutes may be genrally sati afactory. When it is found necessary to add additional alcohol for spray purposes to per- mit application of the r
21、equisite thin continuous film, to mini- mize “cobwebbing“ or s stringing,! the minimum drying period of 60 minutes may have to be extended. (b) If painting is done below 80 F or under high relative humidity, or both, the minimum drying period of the wash primer may have to be increased for an additi
22、onal 30 miaBtes before topcoating with primer. (c) If practice panels indicate the pretreatment coating will blush, the various diluentsspecified in 4.2m3.1(c) and techniques bf. application specified in 4.3.1-3 should be made as a starting point for local spraying application, When diacetone alcoho
23、l or any of the other blush-retardant solvents are used as the diluent, a dwng time of not less than 90 minutes is required prior to topcoating. (d) If the wash primer had been redeposited with butyl alcohol as specified in 4.3.1.3.1, a minimum of 45 minutes should be allowed for drying before topoo
24、ating or sufficient time for the redeposited film to thoroughly dry hard and tough, -and not be aapable of removt. al with the fingernd1 or a cloth saturated with thinner conforming to Specification TT-T-266, as specified in 4.3.1.3. (e) The wash primer coating should always be checked by the finger
25、nail method starting 30 minutes after spraying to determine hardness and resistance to removal. Even with the use of the blush-retard- ant thinners, a temporary blush, disappearing within 15 to 20 minutes, may occur. When such a cond-ttion occurs and the film resists scratching with the thumbnail, t
26、opcoating may proceed. 4.5 - In srde2 to obtain the full gloss of the exterior topcoat, i is advisable to dry scuff the wash primer coati-dg light- ly with either No, 320 or No, 400 sandpaper to remove overspray and smooth out nibs before applying the primer. Any dust resulting from this operation s
27、hall be removed by tack ragging before applying the primer. Nm., clean.kl also, speoi- ficatian MIL-C-153328 may gel if thinned as required for applica- tion under low humidity conditions. 5.2 Practice panels.- To familiarize personnel with coating tmhnTques, equipment, thinning ratios, atmospheric
28、conatima, etcI, practice -panels should be used before starting actual coating on the aircraft, 5.3 Thickness control.- To control thickness, it is recommended that panels be taped to the but also deletes and prohibits the use of lampblack so as to increase rerlectance of white topcoats, thus decrea
29、sing thermal pulse absorption. 7 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-C-8507D 80 m 7777706 0078755 6 m I Custodians: Navy - Weps Air Force - AS Preparing activity: Navy - Weps Reviewer activity: Navy - Weps Air Force - ASD User activit
30、y: Navy - Weps Air Force - AS) Review/user information is current as of the date of this document. For future. doordination of changes to this document, draft circulation should be based on Che information in the current DoD Index of Specifications and Standards. 8 5% c C Provided by IHSNot for Resa
31、leNo reproduction or networking permitted without license from IHS-,-,-30.2 Material precautions.- Only matertals from the same kit shall be mljred, except that two or more kits may be mixed in the same vessel, provided the. kits are all manufactured by the same vendor. Kits will be furnished to con
32、tain the requis- ite amounts of pigmented resin component and clear acid component. If smaller quan- tities are required for touchup, proportion the quantities in accordance with para- graph 4.2.2. It is prohibited to substitute the resln component or acid component 9 MIL-C-$507D(ASC) APPENDIX Gener
33、al krcraft Appli-cation Procedures 10. SCOPE- This appendix contains a summary of application and finishing procedures. 20. APPLICABLE DOCUMENTS 20.1 The following documents of the issue in effect on date of invitation for bids or request for proposal, form a part of this specification to the ex,ten
34、t specified herein: SPECIFICATIONS Federal P-c-437 P-C-44.4 TT-T-291 Military MIL-“3171 MIL-C-5lJ.O m-c -5 5a MIL-F-7179 MIL-C-8514 ML-R-8633 MIL-F-18264. MIL-C -18687 MIL-S-18718 MIL-C-2254.2 MIL-C -22543 Cleaning Gompbund, High Pressure Steam) Cleaner Cleaning Compound, Solvent, Grease Emulsifying
35、 Thinner, Paint, Volatile Mineral Spirits (Petroleum Spirit S) Magnesium Alloy, Process .f6r Cormsfon Protectlon of Cleaning Compound, Aluminum Surf aye, Non-Flame-Sust.aid:lg CheLcal Hirns for AlUrninuni and AlwrLnum Alloys Firdshes and Coatings, General Specification for Coating Compound!, Metal P
36、retreatment, Resn-Acid Remover, Paint, Nonflammable, Water-Rinsable Finishes, Organic, Aircraft, Applicatlon and Control of Cleaning Compound, Aircraft Swf ace Solvent S, Safety Cleaning Compound, Liquid, High Pressure Cleaner Cleaning Compound, Water-EmulBion 30. APPLICATION AND FINISHING PROCEDURE
37、S 30.1 Kit composition.- The pretreatment coating. conforming to Specification MIL-C-8514 is supplied as a two-component kit wherein the two components are ad- mixed just prior to use. One component contains plgment ground in polyvinyl butyral resin, while the other component is composed of phosphor
38、ic acid in an alcohol solu- tion. These components, as separately packaged unlts, generally have excellent storage stability, but when admixed, storage life is limited, Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-C-8507D 80 m 9777706 0098957
39、T m .I MIL-C4507D(ASG) from another manufacturer, because if awed materTa1 exhibits unsatisfactory propertis its source could not be determined. It is mandatry that established mixing ratios are followed, othemi.se the coating will exhibit unsatisfactory prop- erties, such as poor adhesion, poor che
40、mical resistance, or slow or a nondrying fllm. 30.3 Preparation of metal surfaces.- Metal surfaces shall have been surface treated before assembly and shall have received therequisite insulating coatings between faying surfaces in accordance with Specification “F-7179. A brhf summary of the applicab
41、le surface preparation and priming sequence- requirements, contained in Specification MIL-F-18264 and related documents, is contained in 304 and table II herein a3 a guide. These do not replace or supersede the more exten- sive and detailed requirements of the applicable spec5fications. 30.4 Bare sW
42、faces.- Unpainted surfaces which require painting after complete assembly or after stripping with remover conforming to Specification MIL-R-8633 should be treated as follows, prior to application of the coating, 30.4.1 Masking.- Prior to surface cleaning, chemiml treatments, or painting areas such a
43、s canopy, windsMeld, radome, or transparent light covers shall be masked with masking material and taped in place. Gu cancpy or windshield, tape shall be applied to the frames adjacerlt to the transparerit areas bat shall not con- tact the plastic or glass. All exposed portions or actuated rods pass
44、ing through hydraulic seals shall be protected from any material application during cleaning or finishing to prevent damaging seals* All other areas requiring protection shall be masked. Any residue left by maski-ng shall be removed with safety solvent conforming to Specification MIL-S-18718, 30.4.2
45、 Cleaning.- Surfaces which are not clean will not only accelerate corrosion, but will weaken adhesion of subsequent Zinishes. Therefore, removal of grease, oil, and other gross surface contarninants shall be accomplished by aqueous solutions conforming to Specification MIL*-22543; water-emulsion typ
46、e cleaning compound.or steam cleaning with material confoang to SpecificatTon MIL-C-22542, liquid cleaning compound, high-pressure cleaner (about 1 quart to 50 gallons of water) or steam cleaning with material conforming to Specification P-C-437 (about 2 ounces of compound per gallon of water). The
47、spray shall be kept in motion while impinging on the surface to avoid overheating of the surface skin. All residue shall be finished off with hot or cold water rinse. 30.4.3 Removal of surface oxide and trace contaminants on aluminum and magnesium.- Removal of surface oxides and trace contaminants o
48、n aluminum and magne- sium surfaces after cleaning operations, and while still wet, should be accomplished with material conforming to type II of Specification MIL-C-5LJ0, mixed with an qual volume of water. Application should be with soft bristle brushes working from bottom to kop. The material sho
49、uld be allowed to react with alminwu for 15 to 30 minutes, and with magnesium for 5 minutes (maximw) and then rinsed with water, brushing all screws, rivet heads and faying surfaces to insure removal, particularly on magnesium to avoid severe pitting attack. Use of vacuum to dry out seams, rivets, eta, 2s recommended, (Warning: Avoid trapping solution in crevices by adequate masking to prevent entry of solution into inaccessible areas,) At this s
