Rudder Blade

The rudder blade is not made from solid timber as suggested by Dudley Dix but from ply restovers. In order to make it not too heavy it is hollow inside. The outside of the blade is carbon coated. I had good luck and got a fitting restover carbon fabric restover quite cheap. The photos show the production steps executed during December.

Fore Bottom Segments Planked

The ply is stiched to the backbone by using copper wire from electric cables. The shafted joint between bulkheads C and D is fixed by some loads I had culled me on the fly.

 

 

 

Working time been invested: 804 hours

Lower Side Of The Keel Shaft Before Planking

The upper photo shows the lower side of the keel shaft after stringers and bulkheads have been faired and are prepared for planking now.

The lower photo shows the thickness off the coating inside the keel shaft. The epoxy-copper-oxide is about 1mm thick. As scale bar one can use the thickness of the 12mm-7-layer plywood of the shaft.

Aft Bottom Segments Attached

First Hull Segment Attached

Engine Shaft And Anchor Case

In contrast to the original design, the TRÄHOLM will get no outboard engine, but an electric engine mounted in the shaft. The both photos on the left side show the shaft.

The photos on the right side show the future anchor case. I set the bottom in place before planking the ship's side.

 

Upper left photo: Shaft from downside before bottom segments set in place and before cockpit floor is opened.

 

Lower left photo: Shaft from upside after cockpit floor has been opened.

 

Doubling The Tangent Stringers

The tangent stringers are the transition from the flat ship's side and flat bottom  to the round radius sections. The tangent stringers have to be doubled to join the plywood segments. The doubling is made from a 10 mm ply strip of 75 mm width. I had already scarfed the plywood strips to 7.5 m length from restovers.

Doubling the upper tangent stringer on starboard side.

Doubling the lower tangent stringer on starboard side.

Preparing Bulkhead Slots And Stringers For Attaching The Ply-Doubler

Building The Keel Shaft

Inserting The Cockpit Floor.

Straightedges are fixed to the bulkheads by screw clamps in order to ensure their flatness and exact positioning.

 

 

Sheer Clamp

I bought mahogany batten for making the sheer clamps. A first attempt to strake it to the bulkheads failed. The stuff is to stiff. No chance! Therefore I decided to split the battens in order to make them more flexible.

Straking the split battens to the bulkheads was a quite easy task.
Additional advantage: after glueing both halfs together less tension is left into the sheer clamps.

 

Working time been invested: 546 hours

Coming Back To The Bulb Slabs

The bulb slabs have to be covered. That will be the next task. At first the warty surface are filled. The feedthroughs are temporary sealed with wine bottle cork.

 

Then the slabs are glass coated using the WEST-System vacuum bagging system.

Finally a layer epoxy with Cu₂O-filler against fouling. Ready!

Working time been invested: 522 hours

Turning Back To The Keel Foil

Variety is fun. Therefore I turn back to the keel foil. It is time to coat it by carbon fabric. I have chosen carbon instead of glass fabric because of the higher tensile strength. My keel foil is 350 mm longer than the original one designed by Dudley Dix. The higher bending moment requires stronger material.

Working time been invested: 495 hours