6.2 Deformation Gage—A deformation-measuring device,
with a least reading of 0.001 in. (0.025 mm) for measuring the
movement of the fastener into the wood or wood-base specimen.
7. Sampling
7.1 Sampling shall provide for selection of representative
test specimens which are appropriate to the objectives of the
testing program.
7.2 Sample size shall be estimated using procedures in
Practice D 2915.
NOTE 1—The precision required, the manner of sampling, and the
number of tests will depend upon the specific test objectives. General
experience indicates that the coefficient of variation from embedment tests
ranges from 15 to 30 %.
8. Specimens
8.1 Wood members shall be selected, and the dowel positioned
in such a way that the results are not affected by knots,
cross grain, or other natural or manufacturing characteristics,
unless the objective of the study is to determine the effect of
such variables. Frequently, this will necessitate selecting members
which are essentially clear and straight grained. For
wood-based products, specimens shall be selected with regard
to manufactured characteristics.
8.2 Specimen Dimensions:
8.2.1 Specimens shall consist of a rectangular parallelepiped
member with half a dowel hole across one face (see Fig.
1).
8.2.2 For solid wood and wood composites, minimum
dimensions shall be made large enough so splitting does not
occur during fabrication and not less than as follows (see Fig.
1):
Thickness $ the smaller of 11⁄2 in. (38 mm), or 2 dowel diameters
Width $ the larger of 2 in. (50 mm) or 4 dowel diameters
Length $ the larger of 2 in. (50 mm) or 4 dowel diameters