- Sanded G10 12"x12"x3/8" sheet to remove smooth finish.
- Cut 4-1/4" disk of G10 to serve as backing block.
- Cut 1" hole in disk to accomodate the Groco
3/4" thru-hull fitting
- 1" just a bit too small. Next time use 1-1/8".
- Used a rattail file to open the hole to accomodate the 3/4" thru hull.
- Considered using the 1" hole saw to make the existing hole in the hull for the head raw water perpendicular to the outside surface of the hull. Appeared to me that the hole saw will skip on the slope of the existing hole.
- Used a rattail file to remove material till the outboard side of the existing hole became perpendicular to the outside surface of the hull.
- The mushroom head of the thru hull now sits flat against the outside of the hull. Previously the inboard side showed 4 threads while the outboard side was tight against the hull. (See photos below)
- Considered placing a waxed wooden dowel in the hole and filling the rest with fiberglass mush, but did not.
- Dryfit the thru hull and Groco
flanged ball valve
with the G10 disk. Appears that the thru hull does not need to be trimmed. Had to have another boatowner, Jerry (Melody a 1975 Jeanneau 34) help me dry fit the thru hull.
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