During the winter of 2007 the Saginaw Bay Community Sailing Association is building a EddyCat from plans from
Eddy Shipbuilding of Bay City, Michigan.

LOA - 13'    Beam - 5'    Draft (db up) - 1'8"    (db down) - 4'    Sail Area - 79 sq. ft.    Construction: hard chine 1/4" plywood

The Eddycat is a hard chine, 13’ catboat designed for Eddy Shipbuilding in 1946 by Doug Van Patten.

The boat building class is made up of about 17 students. The class started January 8th, 2007 and will complete on March 28th, 2007 meeting twice a week for three hours.

Week One	Week Two	Week Three	Week Four	Week Five	Week Six
Week Seven	Week Eight	Week Nine	Week Ten	Week Eleven	Week Twelve

Week One and Two
Plans are studied and strategies discussed.

Station forms are laid out then cut from 3/4 inch plywood.

Ash and Douglas fir stock is planned down for Bow stem laminate and boat frames.

The stations are fastened to the strongback and battens are held along the lines to check for the fairness of the hull. Adjustments willl be made to offending stations. Once the hull is fair the stations will be removed for notching for the stringers and keelson.
A female bowstem mold is made and 3/16 X 3 X 54 inch pieces of Ash are clamped in dry to pre-bend them before gluing.

Week Three
Lofting
Because of the variations in the molds from the orginal drawings we decided to do a fullsize lofting of the Eddycat . A grid of the 10 stations lines 15 inches apart was laid out on the lofting sheets on the floor. Points for the keel, chine, and sheer were laid out on the profile and half breadths. Battens were placed and the lines faired. Half breadths dimensions were then transfered to the profile layout and station patterns were drawn. A table of offsets of the stations was then created to be used to correct the orginal station molds.
3/4 by 3 inch Douglas Fir stock was scarfed together to form the Keelson.
1/4 by 3 by 54 inch Ash pieces were laminated together with epoxy and clamped to the bowstem mold.

Week Four
The remaining pieces were laminated to the bowstem, the stem planned and checked against the lofting.
The forms were remeasured against the a table of offsets derived from the full size lofting. A dutchman strip was added to the forms in error and trimmed to the correct dimension. Most of the errors were in the angle and width between the sheer and the chine. The forms were then placed back on the strongback.

Week Five and Six
Four 4 X 8 sheets of 6 mil marine plywood are scarfed for later gluing to form two 4 X 15 sheets for the planking.
The stations again are aligned using levels, tape measures and lasers.

Week Seven
The laminated bowstem is set in place for a test fit.
		The scarfed plywood is covered with glass and epoxy on both sides prior to cutting out the planks.
The stations are checked with battens for alignment and corrections are made to the unfair.
	A set of frames is test fit to a station

Week Eight
Douglas Fir frames are fit to each of the stations.
The planks are cut from the scarfed plwood using oversized patterns made earlier.

Week Nine

The laminated bowstem and keelson are dry fit prior to final gluing together with epoxy.

The keelson, bowstem, transom and chine gussets are epoxied to the frames

2" X 1 1/2" X 20' strips of Sitka spruce were epoxied together to form the mast .

Week Ten and eleven

The keelson is beveled with block planes to conform to the shape of the frames.

The bowstem is beveled with a cooper shave.
	The chief technical advisor carefully inspects the work before planking can begin.

The planks are trimmed to size.
The planks are dry fit and trimmed to fit with planes. All the planks are temporarily fastened in place with waxed screws to the frames.

Week Twelve

The planks that were dry fit the week before were removed then ProSet ® Epoxy is applied to the frames, keelson, transom and bowstem before the planks are fastened in place again.

Excess epoxy that is squeezed out of the seams and the frame/plank joints is removed while still in an uncured state.

The chine, transom and bow were trimmed to remove excess planking before the boat was lifted off the mold.

The hull was removed from the mold and readied for more cleanup and interior fillets.

It looks like a boat!.

The mast gets coated with WEST ® 207 Epoxy.

The Eddycat project is done for 2007.

Our Chief Technogial Advisor says "Good-bye for now"

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Last modified Sunday, 24-Feb-2008 05:24:28 PST