MIL-STD-2199A APPENDIX A
f. If a ply begins at a tapered sleeve end, start spiral winding the tape with edges closely butted,
approximately 2 feet from the sleeve and wind toward the sleeve. The first turn shall overlap to help hold the tape in place. Tapered ends of sleeves are always wrapped proceeding from the shaft up onto the sleeve taper. To end the wrap, take the last several turns with decreasing spiral and increasing overlap so that the final turn on the sleeve ends up normal (90 degrees) to the shaft axis. It may be necessary to either use a narrower tape or dart or slash the tape to eliminate wrinkles and air pockets. Additional plies of tape shall be interspersed with each ply of shaft covering as necessary to fair the covering and sleeve surfaces. After completing this short section, complete the application of the first ply. This is done by going back to the starting point, applying a turn of tape over the first turn which had been previously applied and proceeding to the opposite end of the shaft. (To maintain the same spiral for the continuation of the wrap, the shaft rotation shall be reversed.) The tape shall be applied by spiral winding with
edges butted as closely as possible to avoid gaps in coverage. As described previously, the wrap at the end shall begin to overlap on the last few turns and end up normal to the shaft axis.
g. On larger diameter shafting, the roll of tape may not be long enough to cover the entire shaft. In this event, cut the end of the tape square and start winding a second roll of tape. The first turn of the new roll shall overlap the last turn previously applied on the shaft. Some edge overlap shall be used to ensure that the tape ends are held in place. Alternatively, lengths of tape may be measured out in advance and splicing as necessary may be done by overlapping tape ends 3 to 4 inches and securely stitching them together with fiberglass yarn. This procedure also has the advantage of permitting location and removal of any defects in the tape in advance of the winding operation.
h. After completing the first ply, allow the shaft to continue rotating while the fiberglass wets through; this may take several minutes. The tape shall be transparent and essentially invisible when properly wet-out. Work the resin through the tape and smooth any wrinkles with gloved hand, roller, or squeegee. Add additional resin if needed to assure thorough wetting of the glass tape. Work out wrinkles and entrapped air.
i. Continue by pouring more resin over the shaft as needed to provide a reservoir of resin to wet out the
second ply. Apply the second ply in a similar manner, except begin at the opposite end of the shaft, using a reversed direction of spiral so that edges of this ply cross the first ply. Add additional resin as needed for complete wetting of the tape.
J. Work out entrapped air and wrinkles and proceed with two additional plies of resin and tape alternately reversing the direction of spiral wrap.
k. Upon completion of the four-ply wrap, one or two circumferential turns shall be applied at each end to fair the GRP to the sleeve. A completed GRP application is shown on figure A-14.
FIGURE A-14. Completed GRP application, shown fair with the sleeve.
l. After the fourth ply is wet out and faired with the sleeve-end taper, the entire surface shall be coated with additional resin to ensure complete wetting of the glass tape and to provide a smooth, resin-rich and glossy surface with no evidence of dry glass tape or protruding glass fibers. The surface shall be brushed smooth and excess resin droplets or runs shall be removed before the resin gels (see figure A-15).
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