Sunday 14 February 2016

Lining the Shaft Opening

For lining the shaft opening I cut some pluggable plywood boards. The removed board from opening the cockpit floor has been reused as cover. Unfortunately I could not glue because it is too cold. The hollow space is to be foamed later. The three web-boards of the T-shaped opening are cut out at the end.


Tuesday 9 February 2016

Why an Electric Outboard ?

For a long time I thought about the question on the engine type. A diesel engine was not an option. Too big, too expensive, too heavy. The engine should be installed in a shaft. Therefore an outboard motor would be suitable. The designer recommends a 10-hp outboard for the DIDI 23. But to my mind such an engine would be too heavy for my Träholm and too noisy for longer trips. And what if it does not start in an emergency? As an alternative, I have long been thinking about electric motors. But a big disadvantage is the small cruising range and long charging time. On the other hand in 90% or more cases the cruising range is not really a problem. 

To resolve the issue, I wrote all the arguments in an Excel spreadsheet and arranged them in order of importance. In further spreadsheet columns for various drives I put rating numbers. I set "+1" for advantageous, "-1" for disadvantageous or "0" if neither "+1" nor "-1" is true. Then I summed the products of the ordinal numbers and ratings for each drive.

It turns out, that for my subjective ranking of arguments an electric outborder is the best solution.
In particular, when I complete it with a generator later on and thus get a hybrid drive.

Sunday 7 February 2016

Fitting of the Motor

Dudlex Dix recommends a 10-hp outboard for the DIDI 23.
I have chosen an 4-kW electric outboard type Torqeedo Cruise 4.0 RS.
In terms of propulsion power the Cruise 4.0 RS is comparable with a 8-hp petrol outboard, or in terms of propulsion force even comparable with a 10-hp petrol outboard.