DTIC AD0634951: FINISH SPECIFICATION

DISPOSITION INSTRUCTIONS

QS) Destroy this report when no longer needed. Do not return it to originator.

14. When this report is no longer needed, Department of the Army organizations
will destroy it in accordance with the procedures given in A& 380-5. Navy and Air
Force elements will destroy it in accordance wish applicable directions. Depart¬
ment o£ Defense contractors will destroy the report according to the requirement
of Section 54 of the Industrial Security Manual for Safeguarding Classified Infor¬
mation. All others will return the report to US Army Aviation Materiel Labora¬
tories, Fort Euotis, Virginia 23604.

August 16, 1962

Flight Propulsion Laboratory Department
General Electric Company
Cincinnati 15, Ohio

TABLE OF CONTENTS

Para.

1 .

2 .

2.1

2.2

2.3

2.4
3 .

3.1

3 . 1.1

3 . 1.2

3 . 1.3

3 . 2.1

3 . 3.1

3 . 4.1
3 . 4.1

3 . 4.1

3 . 5.1
3 . kj . i

3 . 7.1

3 . 8.1

3 . 9.1

No.

.1

.2

Page No.

PURPOSE 1

REFERENCE SPECIFICATIONS AND MATERIALS 1

Processes 1

Finishes 1

Sealing Compounds and Rust Preventives 2

Thi liners 2

GENERAL REQUIREMENTS 2

Surface Treatment
Aluminum Alloys

low Strength & Clad Aluminum Alloys

All Other Aluminum Alloys

Magnesium Alloys

Titanium Alloys

Carbon & Low Alloy Steels

Sheet, Plate, Fittings & Shapes

Tubing

Corrosion & Heat Resisting Alloys 4
3rass, Bronze, Copper, Lead or Tin 4
Fiberglass Assemblies 4
Ducts Carrying Hot Gasses 4
Tubing (Plumbing) 4

i i

TABLE OF CONTENTS (Cont'd)

Para. No,
4 . 0.0
4 . 1.0
4 . 2.0

4 . 2.1

4 . 2.2
5.0

5.1

5.2

5.3

5.4

5.5

5.6

Page No,

DISSIMILAR METAL PROTECTION 5

Definition of Dissimilar Materials 5

Faying Surface Protection 3

Magnesium Alloys 0

Dissimilar Materials Other Than Magnesium 5

SPECIAL EXEMPTIONS AND NOTES 5

Lubricated or Functional Surfaces 3

Attaching Parts ®

Surface Treatment ®

Bonded Parts °

Drainage Provisions 6

Tanks 6

FINISH SPECIFICATION FOR MODEL 143 (VZ-11)

1, Purpose. The purpose of this specification is to define

the finishes necessary to assure adequate surface protection for the
materials used in the Army VZ-11 airplanes (Model 143).

In the event of discrepancies relative to finish information
shown on the drawing and the requirements of this specification, the
drawing will govern.

2. Reference Specifications.

2.1 Processes.

j QQ-P-416 Plating, Cadmium (Electro-deposited)

(MPD #30)

MIJLr-C-490 Cleaning and Preparation of Ferrous

and Zinc Coated Surfaces for Or¬
ganic Protective Coatings

MIL-M-3171A-1 Magnesium Alloy; Process for Corrosion-

Protection of

MIL-C-5541 Chemical Films for Aluminum Alloys

(MPD #100)

MII/-A-8625A Anodic Films; Corrosion Protection

(for) Aluminum Alloys (MPD #32)

MPD-102 Dow 17 x*.~>od'. ° for Magnesium Alloy,

Ryan Aeromutical Company Speci-
ficiation

MIL-S-5002 Surface Treatments (Except Priming

and Painting) for Metal Parts in
Aircraft

2.2 Finishes.

MIL-P-8585A Primer Coating, Zinc Chromatic Low

Moisture Sensitivity

MIL-P-15930

Primer, Vinyl Zinc Chromate

2.4

3.0

3.1

MIL-V-6894 Varnish. Oil Type, Gloss Finish, Gly¬

ceryl Phthalate Base

MIL-C-15328 Pre-Treatment, Wash Primers

MIL-P-15930 Primer, Vinyl Zinc Chromate

MIL-L-7178 Lacquer, Aluminized

W. P* Fuller Co. #163-W-52 Lacquer Primer Surfacer

Sealing Compounds and Rust Preventives.

MIL-P-8116 Putty, Zinc-Chromate, General Purpose

MIL-C-11796 Corrosion Preventive, Petrolatum, Hot

Application

MIL-C-16173 Compound, Rust Preventive

3M Company .002 in. Polyester insulating tape

#853

Thinners.

TT-T-266 Thinner, Dope and Lacquer (Cellulose-

Nitrate)

TT-T-548 Toluol

TT-X-916 Xylene

General Requirements.

Surface Treatment

3.1.1 Aluminum Alloys. - The following surface treatments shall

be applied to all aluminum alloys as applicable:

3.1.2 Low Strength and clad aluminum alloys 3003, 5052, 5356, 6061,

clad 2024 and clad 7075:

(a) No chemical treatment required

(b) No organic protective treatment

-2-

3.1.3 All other aluminum alloys not listed in item 3.1.2 shall le-

ceive the following:

(a) Alodine in accordance with Spec. MIL-C-5541
(MPD #100). Anodize per MIL-A-8625A (MPD #32)
is an acceptable alternate treatment.

(b) One coat zinc-chromate primer per MIL-C-5541
(MPD #3 00).

(c) See section 5.0 for exceptions to the above.

3.2.1 Magnesium Alloys. The following surface treatments shall be
applied to all nugnesium alloys:

(a) Dow 17 anodize per Ryan MPD-102

(b) One box coat of MIL-C-15328 wash primer

(c) One box coat of MIL-P-15930 vinyl zinc-chromate
primer

(d) For external applications coat outside surface with
two coats aluminized lacquer per MIL-L-7178

Cut edges and abraded spots on magnesium alloys shall be
touched up with a chrome pickle solution meeting Type I, Specification
MIL-M-3171. Areas treated must be thoroughly rinsed and wiped dry prior
to primer application.

3.3.1 Titanium Alloys. The following surface treatments shall be
applied to all titanium alloys:

(a) No chemical treatment

(b) No organic protective treatment except as specified
under item 4,0 - "Dissimilar Materials Protection".

3.4.1 Carbon and Low Alloy Steels.

3.4.1.1 Sheet, Plate, Fittings and Shapes: All carbon steels and
low alloy 3teels shall receive Type II cadmium plate per Spec. QQ-P-416
(MPD #30). Bolts, studs, washers and articles with portions externally
threaded shall receive a minimum of Class 3 thickness plate.

Classes of cadmium plating are:

Class 1 - .0005" thick

-3-

Class 2 - .0003" thick
Class 3 - .0002' thick

3.4.1-2 Tubing. All carbon and low alloy steel tubing; shall be

cadmium plated per QQ-P-146 (MPD #30) on the exterior. Interior treat¬
ment shall be as follows:

Closed tubing : Coat inside with MIL-C-11796 Class
I rust preventive compound per MPD #39.

Open ended tubing : Phosphate treat interior per
MPD #15 plus one coat of zinc chromate primer.

3.5.1 Corrosion and Heat Resisting Alloys.

(a) No chemical treatment

(b) No organic protective treatment except as
specified under item 4.0 "Dissimilar Materials
Protection."

3.6.1 Rrass, Bronze, Copper, Lead or Tin Alloys, Cadmium plate
per QQ-P-416 (MPD #30) if a dissimilar metal contact exists; otherwise
none required.

3.7.1 Fiberglass Assemblies, All fiberglass sui *. shall be
washed with a solution consisting of equal parts of Shell > u^olv W.

Spec. TT-T-548 or equivalent, and lacquer thinner Spec. TT-T-?66 or
equivalent prior to finishing.

(a) After cleaning as noted above, apply 2 box
coats of W. P. Fuller 163-W-52 or equivalent
lacquer surface primer. Air dry.

(b) Apply aluminum airfoil putty, Sherwin-Williams
No. PX-4045 as necessary. Sand smooth.

(c) Finish with 2 coats MIL-L-7178 aluminized
lacquer.

3.8.1 Ducts Carrying Hot Gases. The finish on all of the hot
ducts shall be as specified on individual detail and assembly drawings,

3.9.1 Tubing (Plumbing lines). Tube fittings and tubing shall net
be painted. The exterior surfaces of aluminum tubing shall be anodized in
accordance with MIL-A-8625A (MPD #32) or alodine per MIL-C-5541.

-4-

a a a - j —. j ■» -n _ _ 4. » -i. j .

*i,u«u uiaaiuujiar miuciittis nvic^uyu,

4.1.0 Definition of Similar and Dissimilar Materials. For the

purposes of the finish requirements for this airplane, the following
table defines the dissimilar metal contacts which require the faying
surface protection outlined in Section 4_.2. (See page 7).

4.2.0 Faying Surface Protection. ~ Dissimilar Metal Contacts.

The following protection is required in addition to the
surface protection specified in Section 3.0 of this specification.

4.2..1

Magnesium Alloys.

4.2.1.1 Faying surfaces shall be protected from contacting materials
by (1) layer of .002 in, polyester tape (3M Company #853 or equivalent).

Ihe tape shall overlap the joint by 1/4" on either side wherever possible.

4.2.1.2 Fasteners in Magnesium.

Aluminum fasteners shall be of 5056 material or equivalent.

All other fasteners through magnesium shall be installed with
wet prime. In addition, insulating washers (.010 min. thickness) shall be
used under the fastener heads in contact with the magnesium.

4.2.2

Dissimilar metals other than magnesium.

All faying surfaces shall receive one coat of zinc-chromate
primer with a tolerance of 1/2 ' on interior surfaces coated beyond the
edge of the mating part. Exterior surfaces are to be wiped clean of all
excess primer.

Slip fits shall be assembled using wet zinc-chromate primer.
Press fits f?hal 1 be accomplished with a lightly oiled surfaces on the mating
parts.

5.0 Special Exceptions and Notes.

5.1 Lubricated or Functional Surfaces. Paint coatings shall not

be appliea to those pares which are permanently coated with or housed in
lubricating oil, hydraulic oil oi* grease. Paint coatings shall not be
applied to working surfaces, adjustable screw threads, sliding mechanisms
or to fittings in such a manrer as to cause malfunctioning.

«r*

5.2 Attaching Parts.- Attaching parts such as nuts, '"ashsrs,
rivets, high shear rivets, screws, bushings, spacers etc., need not be
painted in detail except when used in contact with wood or magnesium.

(See Section 4.0).

5.3 Surface Treatment. All metal surfaces shall receive accept¬
able surface treatment prio" to painting. This treatment shall be in
accordance with the requirements of Specification MIL-S-5002.

5.4 Bonded Parts. Aluminum alloy parts which are to be subse¬
quently bonded shall not be painted or primed in the detail. Bonded
assemblies shall receive the organic finish specified m Section 3.0

of this specification.

5.5 Drainage Provisions. Where practicable, drainage provisions
shall be incorporated in the design o' the structure except where such
drainage provisions would interfere with the utility or function of the
part. Drain holes, 1/4' diameter, shall be so located to drain the struc¬
ture when the airplane is in a thiee-point position. When necessary

for structural considerations, drain holes may be reduced to 3/16’’ dia¬
meter.

5.6 Tanks. The interiors of all fluid containing tanks shall
not be pointed or primed.

-o-

Shaded areas denote dissimilar materials.

Chromium Plate