This blog will take you along the different steps of building a 23 foot dropkeel sailboat. The DIDI 23 is one of the available designs for the amateur builder designed by Dudley Dix. The boat is built as a radius chine trailer sailer from plywood with bulb dropkeel.
ABOUT ME
I am 64, married, have two adult children and working as engineer for rf techniques at a physical research centre of the Helmholtz Association. I live close to the Elbe river in a suburb of Hamburg, Germany.
Sunday, 26 July 2020
Friday, 17 July 2020
Antifouling Peels Off
My son discovered some small white spots on the port side next to the keel. A closer inspection showed that the antifouling is peeling off. Fortunately, only the small area next to the keel seems to be affected. But I don't know what the reason could be. I will investigate it the next days.
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| Area where the antifouling peeled off, after cleaning with a steel brush and washing with salmiak-water |
Subsequent entry:
The reason for the poor adhesion of the antifouling is probably moisture from condensation or very humid conditions during curing. Thus a waxy film appeared on surface of cured epoxy.
The reason for the poor adhesion of the antifouling is probably moisture from condensation or very humid conditions during curing. Thus a waxy film appeared on surface of cured epoxy.
Sunday, 5 July 2020
Trim of the Boat Improved
When the boat was first launched in July 2018, it floated well on the DWL. But only if the crew was evenly distributed on the boat. As soon as there were more than two crew members in the cockpit, the scoop was flooded.
| 28th July 2018 after launching. The boat floats well on DWL |
In order to overcome the problem, I decided to shifted the engine batteries (120 kg) from bulkhead G to bulkhead C.
I will see whether the action was successful in a few days when the boat goes to water.
| Engine batteries shifted from bulkhead G to bulkhead C. |
Sunday, 21 June 2020
Installing A Depth Sounder
I have long resisted drilling a hole through the hull. But after some ground contacts it seams meaningful to me to install a depth sounder.
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| Hole for the depth sounder in front of bulkhead B |
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| The Hole for the depth sounder met the old trailer support mark |
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| 3 cm Sapelli for strengthen the mounting area |
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| I backed the hole with a piece of copper tube |
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| Depth sounder mounting kit |
| The sapelli strengthening is painted |
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| To prevent for leakage water I glued a plastic collar around the strengthening |
Friday, 19 June 2020
Installing Instruments
After the mishap with the cutout for the compass on the wrong side, the hole on starboardside has to be concealed. Unfortunately the cutout is larger than required for the depth sounder and the wind display. In order to overcome the problem I decided to build an alcove for the instruments.
Sunday, 14 June 2020
Cutout for the Compass on the Wrong Side
For many years it was clear to me that the compass should be installed on the port side, next to the companionway. The navigation instruments should be installed on the starboard side.
On the day I wanted to saw the compass cutout, my dear wife also happened to be at the shipyard. She showered me with arguments about why the compass should be installed on the starboard side. Since she has had good ideas many times and I just couldn't think of any counter-arguments, I gave in and sawed the cutout on the starboard side.
The next evening, just before I fell asleep, I realized why the compass should be on the port side. It should be as far as possible from electrical instruments and the switch panel in order to protect it from magnetic stray fields!
For a few days I wondered if I should take the risk of installing instruments and compass so close together. Then I decided to do it not. So I sawed a second compass cutout on the port side.
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| One compass but two cutouts |
Sunday, 10 November 2019
The Boat is Ready
The boat is now ready (by definition). Of course there is still a lot of work to do. But remaining work, maintainance work and improvement work already overlap. That's why I decided after two days of successful sailing on the Elbe river
Finished! It's done!
For interested self-builders I have drawn up my working hours and the costs.
It is easy to see that you do not save money when building your own boat - quite apart from the unpaid working hours! But one end up with a really unique boat.
| The fit-lines show that building Träholm was no hard work and not very expensive in average. It took just about 1 hour and 7 minutes per day at costs of 23 € per day |
| Cost allocation table. It may come as a surprise to one or the other how high the percentage of building site rent can be. About 19 %! |
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