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alloy motorsailer

Bob Kupps

Sun, Jan 6, 2008 7:56 AM

Thanks for the advice etc.To answer some of the recent questions posted:

Let me first say that IMO if cost is no object a much lighter and, if you put in enough Kevlar, Carbon etc.as strong or perhaps even stronger/tougher, hull can be made in composite. In my particular case I went this route primarily for 1) cost reasons and 2) the fact that the design was already being built relatively nearby as opposed to say, Paraguay. Alloy construction offered another advantage over composite that was particularly attractive to me - it was very easily "customizable" so that the considerable rig, tankage and interior modifications I made to the previous 3 versions (and the next one, as depicted on the web page someone kindly discovered and posted) were done with relatively little difficulty or additional cost. I suspect the biggest drawback to this approach will be in bridge deck clearance which I estimate will be in the neighborhood of 70 cm fully loaded.

As already pointed out, the performance observed on the delivery trip, while encouraging, may suffer substantially one the weight and windage of the rig and remaining fit out are added. Naturally I am interested in obtaining accurate performance numbers once the boat is re-launched and I will be happy to post them. Anecdotal performance reports from version #1 have also been quite encouraging.

I am also installing a 150A DC genset and 750 watt solar panel array (the motors have 80 A alts) along with two phased 3kW 12VDC/230VAC/50Hz inverters and relying on an induction cooktop and microwave oven for cooking instead of gas. The house bank is 750 Ah AGM. Water maker will be a locally produced 230 VAC 150 l/hr unit.

Both engines as well as the genset are gravity fueled from (and return to) a central 80+ liter day tank through separate 2 micron filters. The day tank is in turn topped up by 2 transfer pumps manifolded to a big Racor fuel/water separator with a 30 micron filter drawing from the two 400+ liter bilge tanks. The day tank has a Cruzpro digital level meter calibrated to 0.1 l resolution so we can get decent consumption measurements.

I will post how all these various approaches actually work out in practice...Bob

Never miss a thing. Make Yahoo your homepage.

Thanks for the advice etc.To answer some of the recent questions posted: Let me first say that IMO if cost is no object a much lighter and, if you put in enough Kevlar, Carbon etc.as strong or perhaps even stronger/tougher, hull can be made in composite. In my particular case I went this route primarily for 1) cost reasons and 2) the fact that the design was already being built relatively nearby as opposed to say, Paraguay. Alloy construction offered another advantage over composite that was particularly attractive to me - it was very easily "customizable" so that the considerable rig, tankage and interior modifications I made to the previous 3 versions (and the next one, as depicted on the web page someone kindly discovered and posted) were done with relatively little difficulty or additional cost. I suspect the biggest drawback to this approach will be in bridge deck clearance which I estimate will be in the neighborhood of 70 cm fully loaded. As already pointed out, the performance observed on the delivery trip, while encouraging, may suffer substantially one the weight and windage of the rig and remaining fit out are added. Naturally I am interested in obtaining accurate performance numbers once the boat is re-launched and I will be happy to post them. Anecdotal performance reports from version #1 have also been quite encouraging. I am also installing a 150A DC genset and 750 watt solar panel array (the motors have 80 A alts) along with two phased 3kW 12VDC/230VAC/50Hz inverters and relying on an induction cooktop and microwave oven for cooking instead of gas. The house bank is 750 Ah AGM. Water maker will be a locally produced 230 VAC 150 l/hr unit. Both engines as well as the genset are gravity fueled from (and return to) a central 80+ liter day tank through separate 2 micron filters. The day tank is in turn topped up by 2 transfer pumps manifolded to a big Racor fuel/water separator with a 30 micron filter drawing from the two 400+ liter bilge tanks. The day tank has a Cruzpro digital level meter calibrated to 0.1 l resolution so we can get decent consumption measurements. I will post how all these various approaches actually work out in practice...Bob --------------------------------- Never miss a thing. Make Yahoo your homepage.