Since publishing the bulb mould plans there has been a couple of requests for a drawing of only the bulb. Here it is. It’s a round cross section 350mm long NACA 0010-34 bulb.
I’m using a feature of Adobe Acrobat 6.0 to attach a DXF version to the PDF file. Open the PDF in acrobat reader and access the DXF by right-clicking on the paper-clip on the right and choose “save embedded file to disk”.
Søren Andresen (DEN) sent me the plans for his own design with which he won the 2005 Nordic Championship and placed 2nd in 2004. He also sailed it into 35. place in the 2004 Euro Champs in Arcos/Spain.
The PDF file contains the sections and a drawing with the mast and keel positions but you should really download the DXF file and printout accurate sections with a CAD program if you want to build the boat.
Søren Andresen (DEN) uses this interesting arm winch setup on his boat.
The idea is that by attaching the jib and mainsheet at different points wrt. the block on the arm you can get unequal travel on the sheets. As shown here the mainsail can be adjusted virtually independently of the jib sheet when close hauled.
A number of people were interested in it at the Euros in Arcos so Søren has made a detailed drawing and kindly allowed me to publish it
Getting the leech points correct when building a mainsail can be quite challenging.
Thomas Dreyer(GER) emailed me with this drawing+text about how to get the geometry correct when you are building an IOM (or M) mainsail.
Lester Gilbert has a similar kind of drawing at his site: “Measuring an IOM Mainsail”
Text is currently only on German, if anyone more fluent than me in German wants to send in an English translation then that would be great ! (Or someone who is good at programming could make a program that calculates the shape…)
Our bulb moulds are CNC milled from aluminium and more than 15 bulbs have been made successfully from them.
Note that it could be useful to make the hole through which lead is poured in a little larger than shown on the plan.
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Charles Detriche has kindly allowed me to publish one of his IOM designs. This one is called “Sliver”.
Update 2006Dec07: Sliver hull in IGES format
Charles Detriche has kindly allowed me to publish one of his IOM designs. This one is called “Arrow”.
Update 2006Dec07: Arrow hull in IGES format
The various sail measurements from the IOM class rule illustrated in a drawing. Prints all three rigs on one A4 paper.
A diagram showing the measurements needed when building a set of IOM rigs. The table shows measurements taken from rigging guides and plans by world champions in the class: Craig Smith (New Zealand 1997), Graham Bantock (France 1994 and Malta 1999) and Martin Roberts (Croatia 2001).
Weights for the Italiko which I sailed at the 2003 IOM World Championships in Vancouver Canada.
