A Boat is Born, Part IV

Makaira’s hull is being constructed via infusion. Resin, under a vacuum, is drawn through feed lines. This process results in a lightweight, yet sturdy hull. Note the red resin being drawn up the transom.This is the fourth installment of an exclusive six-part series in which PMY has been bringing you a first-hand account of

By Mike Smith

March 1, 2009

This is the fourth installment of an exclusive six-part series in which PMY has been bringing you a first-hand account of what it’s like to conceive a new boat model and bring her to market. The idea started with a mid-60-foot-size-range battlewagon and a name, Makaira. The goal: build a vessel that would incorporate the latest design concepts, advanced materials, and efficient construction methods; a boat that would be like nothing that had come before her. There were meetings, ideas were sketched out, revisions made, more meetings, and even more revisions. Now the time for meetings and revisions is over. It’s time to build the boat.

thousands of man-hours have been spent dreaming, designing, and planning the Makaira 64. Throughout its two-year-plus quest to create a next-generation sportfisherman, the builder has addressed myriad issues that will ultimately decide whether or not this vessel achieves the form and function goals set for her.

With a variety of build options and materials to choose from, Makaira’s crew entered the construction phase to make its long-awaited vision of this boat into a tangible reality.

The challenge was picking a manufacturing technique that would provide the strength necessary for a boat that would have to make regular 100-mile-plus canyon runs without incurring excessive weight. In addition, the method had to be conducive to a production-boat pace. After examining a range of options, the builder, along with its design firm Applied Concepts Unleashed (ACU), decided to go with vacuum infusion.

Infusing this 64-footer starts where it does with most boats: the hull mold. Gelcoat is applied to the mold, and then it’s skin-coated by hand using fiberglass mat and resin. Once the skincoat has cured, layers of dry laminates are applied to the mold with contact cement securing each laminate. This process ensures even and proper placement both below and above the CoreCell core. One inch of coring goes in the hull sides while two stacked one-inch cores with laminate between (i.e., sandwich construction) cover the bottom. Makaira’s crew and ACU decided on a laminate schedule that exceeds that required by American Boat and Yacht Council (ABYC) standards. The result should be a hull with significant weight savings compared to a conventional non-cored one, as well as one that can withstand the rigors of frequent offshore use.

Increasing strength while using less material is accomplished via the vacuum process. After the dry laminates are in place, plastic feed and vacuum lines are installed into the mold. Next the laminate is sealed in a large plastic bag and the vacuum is engaged. Pressures are closely monitored to ensure there are no leaks. If one is detected it can be located with an ultrasonic detector and sealed with tacky tape.

Once it’s determined that the tubes are leak-free, suction is applied. The feed lines—as the name implies—carry resin into the laminate while the vacuum lines draw out the air. Resin is pulled through the laminate as air is evacuated. When the laminate is fully saturated, all voids are eliminated and any excess resin is drawn out through the vacuum. Thus the laminate cannot be over-saturated and the optimal glass-to-resin ratio is achieved, creating a strong and lightweight laminate.