A Measured Interlude


It is said the longest journey starts with a single step. A variation on this could be the simplest boat can be built if you just stop faffing around, go to the shed and actually finish the thing! Sometimes though, to stretch this metaphor to its tortured conclusion, you can do both. And that is what happened a few months ago when Rachel and I journeyed to the American isthmus, in particular, Costa Rica!


I first heard about SailCargo and their exciting project over a year ago when trawling the web looking for examples of real sailing ships still moving freight today. This very small (but growing) pocket of the global logistics chain tends to use refurbished vessels built over a century ago. SailCargo, however, are actually building a brand new vessel, the first of which will be named Ceiba, from scratch, using traditional methods and materials. With a few high-tech additions like electric motors (which can generate power when sailing) a modest battery bank and modern comm’s gear, SailCargo plan to move high-value, fair trade products like coffee and rum along the American Pacific coast with zero emissions or fossil fuel consumption.

One day in the not too distant future, either through a global agreement and regulations, or unfortunately the far more likely outcome, when we simply run out of oil, the only way to move freight globally again will be to use the wind and waves (no doubt the wealthy will be able to afford bio-ethanol powered jets or similar, but plebs like us will have to make do with the basics). As a lover of boats, to me it seems pragmatic and eminently sensible to get started on this eventuality now, whilst we still have a link to tools and knowledge from the relatively recent sailing past. Also, it is just a cool project to build a large wooden ship in this day and age!


With that in mind, Rachel and I set off for Central America (argh, a jet-powered plane, we are hypocrites!), hired a simple and dependable Suzuki Jimny, and hit the Pacific coast of Costa Rica. The plan, use survey equipment generously provided by Trimble to conduct a hydrographic survey of the surrounding waterways and 3D laser scan of Ceiba under construction. This data can be used to assist with launch planning, design and alignment checks on Ceiba’s frames and long term shipyard planning.

Rachel started off as assistant surveyor, but I now understand I was actually the assistant and she was number one surveyor
Survey grade GPS receivers provided local coordinates with centimetre accuracy
After the GPS gear has computed positions, the SX10, a 3D laser scanner, measures Ceiba and the surrounding shipyard. The SX10 fires an invisible laser at 26,600 times a second out to 600m with an accuracy of 2-3mm
By placing the SX10 in different locations to eliminate line-of-sight blockages and shadows, a very large 3D point cloud representation of the site is generated
Low tide is the perfect time to scan the river bottom. Watch out for croc’s!
Tools of the trade. The remaining river bed was surveyed using more traditional tools, a line and heavy sinker.
In shallow, muddy water, echosounders can often report incorrect depths. So instead, we dropped lines over the side and recorded the height (depth) and GPS position
The data is combined, along with an average high tide position, to create a bottom survey and estimated grounding zones for the completed Ceiba when she is launched in the next two years

To give a visualisation of the accuracy and density of the data generated, the video below shows the Ceiba as she was in July, 2019 (with 11 frames installed). Overlaid on the point cloud of Ceiba, are original 3D CAD drawings. The measurements show that Dani and Lynx’s team at SailCargo have done amazing work with near perfect alignment of design and reality.

It wasn’t all hard work and surveying though. After a week of sleeping in the treehouse, woken at dawn by howler monkeys and delicious breakfast and lunches made by the local village women’s association, it was time to finish up the survey and see more of Costa Rica before heading back to New Zealand. We had enough time to see volcanoes, the Caribbean and Pacific coasts plus lots and lots of jungle, mountains and birds:

Rachel and I would like to thank Dani and Lynx at SailCargo for hosting us and letting us be a part of this fascinating project. We look forward to seeing Ceiba on the waves in the very near future. If you would like to know more, check out their website and youtube channel.




  1. Hi, Damo!

    Thanks to you, I have now had my own little vacation. What an incredible place Costa Rica is; so different from my world. You all had so many great shots of the wildlife.

    That is such a worthy project, and I am glad that you and Rachel are able to be a part of it.

    Pam in Virginia

    Liked by 1 person

  2. […] diversions followed, including a prize winning race down the Waikato River and a visit to a real shipyard in Costa Rica. Eventually, I did finally get around to making the oars, and just recently, a simple sail rig. […]


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