Hydraulic motors. You mention the problems with running your anchor windlass, the need for large wire size to minimize voltage drop on the long run to the bow. Why not power the windlass with a hydraulic motor? You already have a pump onboard for the auto pilot, even adding an additional pump would provide some redundancy for the autopilot system. Now all you need is a tiny motor and a couple skinny (1/4 in od) lines running up to the bow. These motors are robust, simple, easily speed and overload controlled, corrosion resistant (I own a chemical plant, believe me I know about corrosion!), very lightweight… I first saw these used at a plant in Norway. All the agitators drive motors (probably 10 total) were run by a single hydraulic drive pump. Speaking of multiple motors, how about that big power winch you use on Beowulf? Slap a hydraulic motor on that thing too and get rid of the need for a 24 volt electric system all together!
Hi Russ: This is a more complex issue than it may appear at first. I think we cover it in some detail in Offshore Cruising Encyclopedia, but here are a few basics.
1-When comparing weight and cost, you need to add in all of the pieces.
2-Hydraulic hoses may be lighter than wire (but not by much once they are filled with oil), and the motors may be lighter, but by the time you add in pumps, valves, reservoirs, and heat exchangers, the total system is invariably heavier.
3-Hydraulics are noisy, and they always, 100% guaranteed, leak. I’ve used them on a number of boats, and for most yachts, they don’t make sense to me. Regards – Steve
Posted by Steve Dashew (November 30, 1999)
