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 TB 55-1900-201-45/1
2-8. Inspection of Fastenings.
a. A wood boat is no better than its fastenings. The inspection of hull fasteners is difficult since most fasteners
are countersunk and covered with wooden plugs. The hull fasteners shall be extracted at random and examined for dete-
rioration. The fasteners shall be extracted from the underwater area, wind and water area, the stem and stern during
scheduled drydocking. A condition report of the extracted fasteners shall be submitted to the US Army Troop Support
and Aviation Materiel Readiness Command, ATTN: DRSTS-MMM, for evaluation.
b. Planking fastenings which are loose, broken or wasted often result in sprung butts or in planks which are loose
or chatter when sounded with a hammer. When fastenings are loose, it does little permanent good to harden up those
which exist. Additional fastenings, properly placed, are the preferred repairs where there is sufficient room to obtain
good holding power without seriously weakening the planking. If there is not room, holes in the substructure from the old
fastenings will be properly plugged and new fastenings of equivalent strength shall be driven. Loose planking can also
result from deteriorated frames and other substructure in which case refastening is useless, unless the structure is first
made sound.
c. Particular attention shall be given exposed hull fittings and through bolts. These shall be sounded with a
hammer, and if suspected, some shall be pulled for inspection. It is advisable to pry up on exposed bolt heads with a
probe or screw driver. Often the bolt will be completely wasted away in the middle, at the faying surface of the joint, and
will come out when pried up. This is caused by moisture accumulation which, besides wasting the fastenings, forms an
excellent place for decay to start.
2-9. Inspection of Caulking.
a. Caulking is subject to deterioration. It is advisable to search the seams in any doubtful areas and re-caulk.
Caulking shall be uniform and well "horsed" home. This can be checked with an awl or a knife. Care should be taken
that the caulking has not been driven clear through the seam.
b. Extensive trouble with caulking is an indication of structural problems. If the hull "works" excessively, the
caulking will be squeezed out. In such cases, the hull structure will have to be made sound before caulking will hold. In
old hulls, where the seams have become enlarged from repeated recaulking, copper or lead strips may have been nailed
over the seams to act as caulking retainers. These are a temporary remedy and are an indication of poor general condi-
tion of the vessel. It is advisable that such strips be removed and the seams inspected for excessive width, poor caulking
and decay. In some cases, wide seams or broken plank edges can be repaired by the use of thin groving pieces partially
filling the wide seams.
2-12
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