Friday, 22 October 2010

Rudder Case

The rudder case design is such that the rudder blade itself can be raised up and down as neccessary for getting in and out of shallow water. This gives better steering control than the kick back style of rudder where very little of the blade is in actual contact with the water.

Sleeves is made by laminating around the rudder blade itself. Flanges made from some foam cut offs, and will be pulled off after laminating

I think the idea that the sleeve will slide off sideways is a little optomistic. Fortunately because the trailing edge end is open, you can prise the sleeve sides apart slightly. Then I pulled some thin strong string down to the leading edge each side, (breaking the resin/tape seal) -then with a tap from a rubber hammer, it just jolts forward slightly and then could be worked off.

Case off, make sure you get it the right way up for trimming! The top and bottom angles are not the same.

Attaching the tube to the sleeve and getting it parallel and perpendicular is tricky to get right, -get it wrong and have wonky rudder! I thought this set up plus gravity should help, as there is very little in the way of referrence points to tell if it is correct or not.
Final laminations added - now need to cut slots for the gudgeons

Slots for gudgeons. Angle grinder and power file. Very messy- black dust everywhere. (Case shown upside down)

Marine carpet for the case lining? Well I hope so. I asked Ian Farrier what  "marine carpet" was, and he directed me here, (but also said that it is no longer available!) :

However it still seems to be available in the UK -as shown above . It appears to be the same material (named - Front Runner Fabric) - it matches the description well .But it does seem thinner than I was expecting. In the uncompressed state it is about 3mm thick, but when squashed goes down to about 1.5mm. I may need to use a double layer I think. (Actually IF say do not use 2 layers, rudder would move in sleeve and steering would be spongy/rubbery)
 Attaching the steering arm to the case.

Mold for making a removable sleeve. The flange plate is my idea to help pull of  the sleeve after laminating.

Sleeve laminated on. These small pieces of cloth are a pain to cut and work with. They keep on lifting off around corners and are prone to distorting badly.

Trial fitting the quadrant, -getting it  perpendicular to the pivot pin is important. I am still not entirely happy with the carbon quadrant, and have decided to line the slots with 3mm Aluminium to try and prevent the steering wire from eroding the carbon over time.

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