English Tech/Engineering Ships, Sailing, Maritime keel measurement/regatta inspection

For the Yngling class the positions of the keel templates are specified by distances along the leading and trailing edges from the base of the keel (despite the fact that the templates are labelled by the height above the base plane, as is the rule for the Soling Class). In practice the two halves of the keel templates should be joined by end plates which are pinned. It is much more convenient to provide a horizontal plate on which the keel rests and then support the template at the correct height by three precision pillars. This allows the template centreline to be aligned with that of the keel, and for the front of the template to touch the leading edge. In the case of the Yngling the pillars were made so as to comply with the distances along the leading and trailing edges. This system makes it easy to align the template, which is then wedged in place for gap measurement.
Care should be taken to ensure that the gap measurement is made at the appropriate edge of the template, and ideally ball bearings of the appropriate minimum and maximum sizes should be used to test the gap.

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