MIL-DTL-43492D
3.3.6 Setting of end clips. Webbing shall be inserted the full depth of the clip. Clips shall be
securely attached without cutting the webbing and the webbing shall lie flat at the point of entry.
3.3.7 Wicking of sewing thread (cup test). There shall be no dripping of water through the
stitching when the tent section is tested as specified in 4.5.2. Seepage or leakage of water at a few
points caused by hydrostatic pressure through needle holes or between plies of a lap seam shall not be
scored as a failure. The seam leakage test is intended to insure that nonwicking thread has been utilized
and that no lubrication has been added to the polyester thread prior to or during the sewing operation.
*3.3.8 Cementing. Cementing shall be in accordance with the following procedure:
a. Surface preparation. Surfaces to be bonded shall be clean and dry prior to
application of the adhesives. Coated cloth surfaces to be bonded shall be thoroughly cleaned by
rubbing with toluene-wetted clean cloths or pads, which may contain a mild, bonding abrasive of 80, or
finer, grit size or may be of a course weave (as for scouring). If abrading is exercised, there shall be no
scuffing or abrading of the base cloth. Separate clean cloths and clean solvent shall be used for final
cleaning wipes. Abrasive coated cloths or pads shall not be used directly on stitching at seams.
b. Adhesive mixing. The ratio of the adhesive mixture shall be as specified on the
drawings. Prior to extracting quantities of the base and accelerator to be mixed, any settlement shall be
uniformly redispersed. Containers for mixing, transfer, and use shall be clean prior to each filling.
Adhesive in the containers shall be covered during transit to work stations and during sustained periods
of non-use to prevent loss of solvent by evaporation. After mixing, the adhesive shall be used only while
sufficiently spreadable to obtain an even coat.
c. Adhesive application. A minimum of two coats of mixed adhesive shall be evenly
spread on the cleaned surfaces to be bonded. The first coat shall be dry to the touch before the
application of the second coat. Prior to assembly, the adhesive coated surfaces shall not be allowed to
be contaminated by a visible layer of dust or other foreign matter. Applied adhesive shall be free of
heavy smears or excessively thick lap edges (resulting from insufficient spreading), thin starved areas,
uncoated areas or other defects characteristic of improper application. The second coat shall be dried
as appropriate for the assembly method to be used; i.e., to a tacky (not wet) aggressive grab condition
for the two-way dry stick method; or to a low-tack (dry condition) for two-way stick, solvent
reactivation method.
d. Assembly. Assembly of components shall be made when the tack and grab of the
adhesive coated surfaces are in a suitable range. Either excess solvent in the adhesive layers or
excessive drying or open time shall be avoided. Surfaces shall be joined in the locations specified on the
drawings, applying adequate pressure and rolling or barring firmly to produce an adequate bond. Care
shall be exercised to avoid finger contact in the adhesive coated areas along the edges of seams,
patches or other bonded parts. Precautions should be taken to prevent adhesive application,
assembling, or curing of an assembly at a temperature below 60o F. The assembled work shall not be
moved to soon or in such a way as to result in edge lifting or decreasing strength of bond until the
adhesive has set. Surfaces shall be assembled on the same day that they were coated, or a third coat of
adhesive shall be applied to each surface. When surfaces have been assembled in an incorrect location,
the adhesive bond may be immediately separated and reset at the proper location. To facilitate
separation, toluene may be applied at the bond line by squirt can or atomizer and the component then
peeled away as the adhesive softens. The excess toluene solvent shall be allowed to evaporate before
resetting the surfaces. When incorrectly located parts are separated and the adhesive is not in an active
condition or has transferred to the other surface, the affected surface shall be given an additional coat of
adhesive before reassembling. Any adhesive residue shall not extend further than ½ inch beyond the
edges of seams strapping, splices, patches or other bonded parts.
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