This is a blog post trying to show how lifting keel system works in N Fun 30 yacht. We do not call it vertical centerboard but lifting keel due to havy weight. It is 650 kg and most of it is in 550 kg led bulb at the bottom end.
Why lifting keel?
There are two reasons for system used:
- Sailing: Thanks to whole ballast placed at the end of keel N Fun 30 yacht is very stable. Unlike swing keel yachts in N Fun there is no gap in keel box when keel is dropped and it doesn’t work as a “brake”
- Practical: Having lifting keel instead of fixed one makes N Fun 30 trailerable (trailer + boat is less than 3500 kg) and gives us opportunity to launch a boat of a slip (video on the right)
Main part of the keel is steel construction with two bolts at the end. Bolts are used to attach led bulb. About 50 cm over the bulb is hydraulic cylinder fixation point. At the very end thin GRP skins are installed to achieve a proper foil shape.
At the top of keel there are two solid blocks installed. They are exactly in the shape of top keel box part. Thanks to this when the keel is completely dropped it is absolutely fixed
In keel box two teflon bearings are installed – at the top and bottom. Bearings are exactly in the shape of keel (+2 mm) what allows to lift and drop the keel easily.
Supporting structure is made of two combined 40 x 80 mm stainless steel sections. It is fixed in a bottom and in the roof of yacht. It is fixation point for top of hydraulic cylinder.
How lifting keel system in N Fun 30 yacht works
Hydraulic cylinder is connected with pipes to hydraulic pump. Electric engine of pump is responsible for lifting the keel (push button UP). To lower a keel (push button DOWN) solenoid valve is activated and keel drops with its own weight. On the pipe responsible for keel going down retarding valve is installed.
If batteries are empty or somehow electric failure happens there is an emergency solution. To lift a keel hand pump is used, to drop a keel ball valve needs to be opened.
Some pictures of interior with lifting keel installed are in gallery
Please do not hesitate to contact us if you have any questions or would like to get some drawings for better understanding the issue.