The photo above is a Twiggy Mk1 from France

This presentation documents the construction of a modified version of Lock Crowther's famous Twiggy Mk 2 trimaran

Thursday, January 26, 2012

Bandsaw and Planer

Walker Turner 16" bandsaw with 5 hp electric motor

  • used a 1" x 4 tpi bimetal blade with alternate set teeth for ripping fir and cedar planks to rough size for stringers, gunnels , keels - blade speed 2400 feet/min.
  • used a Doall 1" x 4 tpi honeycomb knife blade with "0" set teeth and 0.032" kerf for slicing 3/16" cedar strips up to 10" wide (DOALL028) - similar to a hollow ground saber saw blade
  • the cedar veneer was sawn to about 3/16", then planed both sides to 1/8"
  • Ryobi 13" planer was used for planing to finish sizes, removing about 1/64" per pass for the veneer
  • 1/8" cedar veneers were passed through the planer on a true flat 2"x10" spruce plank for support
  • the bandsaw and planer were mounted 10 feet from the feed end of a 26 foot x 18" bench
  • a 24"x24" door was located in the garage wall at the feed end of the bench, and when open 16 foot stock could fit on the feed end by sliding out through the small door

Wednesday, January 25, 2012

Stringer and gunnel details

 stringers with breast hooks at stem

 detail at frame 8

detail at frame 9 and keel for drainage

 stringers with breasthooks at stern

 stringers at bow - plenty of strength

 gunnel doublers tapered at ends

Note tapered stringers to avoid hard spots



Monday, January 9, 2012

Tuesday, December 27, 2011

Frame reinforcement at beams


Aluminum reinforcement plates epoxy glued, and also fastened with aluminum screws on frames that sandwich the crossbeams

Tuesday, December 6, 2011

Planing bench setup


Plenty of stringer, gunnel, and keel stock to be planed to size. 

Monday, December 5, 2011

Float frames done!



Float frames done - epoxy glued, with 6 oz glass cloth/epoxy over plywood, and 3 coats of epoxy over timber.