21 foot guideboat

21 foot guideboat

21 foot guideboat designed for open ocean racing, built by Bill Armitage.

Description

Traditionally guideboats are rowed by a single person. For a number of years guideboats have won the fixed seat single class of the Blackburn Challenge, a tough 20+ mile open ocean race around Cape Ann, Massachusetts—beating whitehalls, ultralights, dories, etc. A racer (Bill Armitage) in the fixed seat doubles class noticed this fact and commissioned me to design a stretch guideboat for the fixed seat doubles class of the race. The design had to be quick-build because of time constraints and shop availability.

This guideboat was constructed using the stitch and tape method, of 5 ml scarfed marine plywood for the hull and frame, with fabric decks. The hull was simplified as much as possible, the scarfed plywood was cut into 3 shapes; one bottom, two matching sides, and two matching chines (some call these bilges). This was sewn together and glued with epoxy and fibreglass tape. It was estimated to weigh about 90 lbs. The beam is typical of a traditional guideboat. The height of  the bow and stern was lowered for windage, burying of the bow in waves has not been a problem.

Design notes

It quickly became evident that for the weights and speeds involved, a long boat would be needed, and simply stretching the 16 footer would not prove satisfactory.

Several digital models were developed, much was discussed by email, and eventually a 21ft, slightly asymmetric hull was chosen for the job.

Early development model for the 21ft guideboat

Race results

  • 2008
    • Blackburn Challenge 1st place in class, and a new class course record.
      (20+ mile open ocean race around Cape Ann, MA)
    • Head of the Weir 1st place in class
      5.5 miles, Hull, MA
    • Row for the Bay 1st overall
      3.5 miles, New Bedford, MA
  • 2007 – 4 firsts out of 4 starts!
    • Blackburn Challenge 1st place in class
    • Head of the Weir 1st place in class
    • Lighthouse to Lighthouse 1st place in class
      14 miles, Westport, CT.
    • Slocum River Regatta 1st place in class
      2 miles, Dartmouth , MA

Race pictures

Construction

Standard stitch and tape construction was employed. With the low number of hull panels the boat went together quickly.

Stitching the 21 foot hull together

Stitching the bilge panel on to the strongback

Construction of a 21 foot guideboat

More stitching of the bilge panels

Guideboat resting on the strongback

21 foot guideboat on the strongback. Note the boat is built upright.

End view of the guideboat hull on the strongback

Clamps hold the ends together straight while glass and epoxy dry inside. No stem is used.


21 foot guideboat nearing completion

21 foot plywood guideboat nearing completion


Six pages of construction pictures of this 21 foot guideboat are available at The John Gardner Chapter of the Traditional Small Craft Association located at the University of Connecticut, Avery Point Campus.