Achieving a Perfect Fit

The complete interior with all cabinetry and furniture components fastened to the sole was taken to Liberty Yachts, for preliminary fitting to the empty hull. We do the fitting at this stage so that we can take the interior back to the shop for all the finish work and details, knowing that when that is done it will drop perfectly into place in the hull when it is brought back for final installation.

In the photo below, you can see the interior suspended over the empty hull by chainfalls attached to the central strongback. The rough fitting has been completed. We begin this process by slowly lowering the interior in from above and cutting away obvious corners and other areas that would prevent it from going further in. The rough cutting is done quickly with such tools as sawsalls and aggressive grinders. As the fit gets closer, we block the sole up a set distance from the hull bottom and begin scribing lines so that we know how much more needs to be cut away.

The view below is from inside the hull, looking from the companionway area into the interior from beneath the sole. Note the plumb bob suspended on centerline from the sole. This and another plumb bob not seen here at the other end insures alignment with the hull centerline as the interior is lowered into place. The contact surfaces, where the interior components such as edges of the cabin sole, bulkheads, and backs of shelves meet the hullsides are marked with a black Sharpie. The crew here is covering all these marked contact areas with clear Mylar packing tape.

Here is a closer view showing the marks and the Mylar tape.

Next we have a view of the interior looking aft from the bow. You can see the ragged edges of the rough cuts we made to get an approximate fit. At this stage is where the Mylar tape comes in. The interior will now be lowered all the way in and all contact edges, including the edges of the cabin sole, bulkheads, and shelf backs will be filled in with a mixture of thickened epoxy, right up to the taped contact points on the hullsides. The Mylar will prevent adhesion to the actual hull while this thickened epoxy cures. When cured, this epoxy filling at the contact edges will be a mold that fits exactly to the inner hullside. The interior will then be lifted out, and the excess epoxy on the sides of the contact surfaces will be sanded flush with each perpendicular plywood part that meets the hull. Since all plywood surfaces will be covered in veneer or paint, the thickened epoxy at the mating surfaces will not show in the finished interior.

We have found this method to work perfectly and by pre-fitting the interior this way, we can be certain that when we return with the finished product that it will drop right into the hull with no further modification.