Issue No. 139, October/November 2012 — Table of Contents
On the cover: A technician at SYBO Composites (St. Augustine, Florida) sprays epoxy-compatible gelcoat ECT120 from the same equipment and with the same procedures as he would for conventional polyester gelcoat. The production boatbuilder has embraced the new gelcoat for epoxy-infused composite models to significantly reduce finishing time and expense and achieve a thicker, high-gloss finish straight out of the mold. Story on page 30.
Photograph courtesy SYBO Composites.
40 The Missing Dimension
by Roby Scalvini
Adding depth retrieval to infrared thermography provides the third dimension, z, in non-destructive composites inspections.
54 A Studied Lack of Depth
by Reuel Parker
How eight shoal-draft monohulls achieve stability under sail and power—offering safe, practical alternatives to deep-draft hullforms.
74 Survivor III
by Dan Spurr
In our third survivor story, lessons come from Ontario, where Mark Bruckmann keeps his door open and a diminished crew busy.
86 Get-Home Systems
by Steve D’Antonio
For long-range, single-engine motoryachts, there are a number of possible backup propulsion systems. Here’s an overview.
96 Making the Best of Narrow Flanges
by Bruce Pfund
Correctly mounting modern marine hardware requires working with greater care and precision than many boat builders and repairers are able to consistently achieve.
108 Takeoff Window
by Jim Brown
A lifetime of adventurous research into sail-driven hydrofoils has led Sam Bradfield to the forefront of design, control, and performance prediction for this still-exotic type.
5 Letters, Etc.
Readers comment on bonding systems, “back-up” engineering, aluminum fabrication failures, the influence of Derek Kelsall, the nature of complexity, the virtue of curiosity, a custom sea chest, tinned wire, sizing electric propulsion motors, and smoke alarms afloat.
compiled by Dan Spurr
C. Raymond Hunt Associates; marine trades training at Skagit Valley College; a partnership of composites innovators in the United Kingdom; Cepheus IX returns to her builder; PRO-SET’s expanding epoxy foam; subscription-based online manuals, warranties, and service schedules; PlanetSolar circumnavigates; and Stabicraft to build for Alaskan fisheries researchers.
30 Practical Solutions
by Ginger Gardiner
Finding a truly compatible gelcoat is a perennial challenge for boatbuilders who employ epoxy resin in closed-molding. One Florida production shop has a solution.
128 Parting Shot
by John Brooks
An experienced boat and paper-airplane designer and builder reflects on the value of simplifying construction ideas and details before they get to the shop floor.
124 New Products and Processes
125 Classified Advertising