Category: Boating, boats, ships and the sea

Two excellent free boat calculators

Sailcalc in operation

Boating enthusiasts love to fiddle with things – for many of us it’s part of the joy of owning and using boats. Some, like me, go further and start to create actual new boat designs, even if we do keep our creations on the small and simple side of the street.

If you’ve tried designing or re-designing a rig, you’ll know that the arithmetic can be tiresome and if you have you’ll be interested in these two calculators developed by one of my friends from the Yahoogroup Boatdesign, Peter Vanderwaart.

The first is Boatcalc, a handy calculator for use with boat hulls modelled using Gregg Carlson’s very useful Chine Hull Developer. See the Boatcalc_documentation. Even if you’re not working on a boat designed using this software, it may be worth reverse-modelling an existing hull in order to make your calculations, and to study its hydrostatics, wetted area and so on.

The second is Sailcalc, a fabulously useful rig calculator that works out centres of effort, sizes and dimensions – from experience, I can tell you that it’s a boon when you’re trying to balanace up the hull of a boat, its skeg and centreboard, and a mast that can only be in one place and a variety of sail options.

Ben Crawshaw looks at the traditional boats of the Spanish coast

Top: barque de mitjana Sant Isidre at Barcelona. Bottom the intriguing hull
of a polbeiro at a boat exhibition. Photos by Ben Crawshaw

Ben Crawshaw of the Invisible Workshop has been putting up some splendid posts about the exotic-looking boats he encounters along Spain’s coasts.

As usual, it’s best to read weblog posts in order – in reverse order to the way they’re presented. So I’d recommend looking at this one on the history of the heavily built boats of Catalonia first. They seem to be built for the grandchildren, in the local saying.

Then turn to this introduction to the polbeiro (just look at that rig and the astonishing tiller!, and this post on the cross-oared rowing technique, which also shows its interesting hull form. I’d say it shows some potential that could be exploited by today’s plywood boat designers.

The next instalment takes us to Barcelona, where Ben runs into the skipper of the Sant Isidre, who he met some time ago while cruising in his Light Trow, Onawind Blue. And finally, he tells something of the astonishing and complicated story of this 1925-built lateen-rigged barque de mitjana, which has done service as sail-powered fishing boat, been used for smuggling, pressed into service as a POUM gunboat during the Spanish Civil War, been used for diving and was finally restored and given her old rig back in 1993.

Finally, you might by now be ready for this whimsical piece about nice old boats that have been used as a kind of garnish for roundabouts. Thanks for this entertaining, informative stuff Ben!

If you can, watch this BBC Alba film about fifies and zulus before it disappears

It’s in Gaelic and subtitled in English, but who cares when it features fifies and the remains of a zulu described by real experts? Click here, and settle back for a few very happy minutes.

My thanks to the kind folks of the Yahoogroup Openboat for pointing out the link.

For more on zulus, fifies and such at intheboatshed.net, click here.