NOTE:  The wash primer is supplied in a two-component kit consisting of a resin base material (4 parts by volume) and an acid accelerator (1 part by volume).
a)  The wash primer base material and acid accelerator must be thoroughly and vigorously agitated just prior to mixing.
b)  Mix the wash primer by adding small amounts of acid accelerator to the base material with constant stirring. Do not add base material to accelerator. Immediately after mixing, the containers should be time and date stamped. Allow the mixed wash primer to stand for 15 minutes minimum before using.
NOTE:  Mixed material has a usable pot life of 4 hours below 90°F and 2 hours above 90°F.
500 
51-21-131 Page 710  BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.  May 01/98 

c)  Thin the mixed wash primer to spraying consistency with 50-50 mixture of ethyl and butyl alcohol. The volume of ethyl/butyl alcohol mixture added must not exceed twice the volume if acid accelerator used.
NOTE:  The spray equipment used for wash primer must be clean before use and should be flushed out with alcohol before and after use. Pressure pot liners and mixing equipment made of stainless steel will resist attack by the acid present in the wash primer.
d)  Spray apply the wash primer in a continuous film to a dry film thickness of
0.2 to 0.4 mil. A single wet spray pass should provide this thickness. Do not attempt to obtain full color hiding.
NOTE:  Too thick a film must be removed with alcohol immediately and replaced with a properly applied film.
e)  Allow the wash primer to dry not less than 45 minutes and not more than 4 hours at 65 to 85°F before over-coating with zinc chromate primer.
NOTE:  Primer films over 4 hours old should be stripped with butyl alcohol or paint stripper and reapplied.
f)  Primer films that are soiled from dust, dirt, or paint over-spray should be carefully cleaned immediately prior to over-coating. Use varnish or linseed oil type tack rags or rags lightly wetted with butyl alcohol.
CAUTION:  BUTYL ALCOHOL WILL REMOVE THE PRIMER IF IMPROPERLY HANDLED.
g)  The dry wash primer may be hand scuffed lightly with 400 grit or finer abrasive paper to obtain a smooth surface for over-coating. Use extreme care to prevent removal of wash primer to bare metal. If sanding is done, clean surface per step f) prior to over-coating.
500 
May 15/71  BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.  51-21-131 Page 711 

2) Zinc chromate primer MIL-P-8585 (apply to surfaces coated with wash primer) a) Agitate the zinc chromate primer vigorously prior to thinning and application. b) Thin the zinc chromate primer with 2 to 2.5 parts, by volume, of toluene to 1 part of primer to obtain spray consistency. Add the thinner to the paint slowly with good agitation. c) Spray apply the zinc chromate primer to a dry film thickness of 0.2 to 0.4 mils. d) Allow the zinc chromate primer to dry at 65 to 85°F for not less than 45 minutes and not more than 72 hours before over-coating. e) The dry zinc chromate primer may be hand scuffed lightly with 400 grit or finer abrasive paper to obtain a smooth surface for over-coating. f) Zinc chromate primer, which is more than 72 hours old shall be removed and reapplied just prior to over-coating. Since stripping removes both wash primer and zinc chromate primer, reapplication of both is required. g) Just prior to over-coating, lightly wipe the painted surfaces with a clean, lintless cloth wet with BMS 3-2 solvent or naphtha and squeezed to remove the excess solvent.
3) BMS 10-11, type 1 primer (apply to surfaces that were previously treated with epoxy primer and did not remove with paint stripper). a) Apply primer per 51-21-51, Chemical and Solvent Resistant Finish -Cleaning/Painting. b) Allow primer to dry per 51-21-51 prior to application of Corogard coating.
500 
51-21-131 Page 712  BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.  Aug 15/71 

4)  Aluminized coating (EC-843 or EC-843S Corogard)
NOTE:  These materials are furnished in two component kits consisting of a resin component and an aluminum powder component (12.5 oz aluminum powder EC-1101 per gallon of resin EC-843 or 9.0 oz aluminum powder EC-1101 per gallon of resin EC-843S).
a)  Strain the resin component through a 60-80 mesh metal sieve into a pressure pot or mixer.
b)  Place the aluminum powder in a separate container and pre-wet the powder by slowly adding sufficient methyl isobutyl ketone or resin component to form a uniform suspension.
c) Strain the aluminum powder suspension through the 60-80 mesh metal sieve into the pressure pot or mixer. d) Agitate the mixture thoroughly by hand or a power mixer to a smooth even blend.
　
中國航空網 m.k6050.com
航空翻譯 www.aviation.cn
本文鏈接地址：737 AMM 飛機維護手冊 結構 STRUCTURES(30)