RC Conversion -  MK/4 Endeavour.

PART 5 - Update On The Shop Bought Rudder.

After sailing the yacht for a few times in various wind conditions, it was found not to be as manageable as the previous MK/4 with the brass rudder so it was decided to increase the size of the rudder. As the deck was glued and pinned in place, it was not just an easy case of swap the rudder assembly and any modifications would have to be made in situ.

After looking at different ways of approaching the process, the rear edge of the blade was filed back to provide a wide working area to allow a Dremmel with a metal toothed saw wheel to run up and down to make a slot of about 3-4mm in depth, the wheel is about 0.7mm thick. The rudder is made of a composite material which was found to melt back with the heat from the cutting wheel, (See photo below), a thin card template was made to be inserted into the slot and was adjusted in shape to provide a suitable enlarged profile. Then the template shape was transferred to some 0.5mm brass sheet and cut out with fine cutting shears and filed for the radius corners. When happy with the final shape, the brass sheet was bonded with Araldite into the rudder slot and left to cure overnight.

Next any excess Araldite was then filed back, the rudder and brass plate was rubbed with sandpaper to provide the key for a skimming of P38 body filler, this was then left overnight to cure. The filler was then rubbed back using various grades of rubbing paper from 80 - 240 to give a smooth profile.

Finally, the rudder was given a couple of coats of Humbrol to seal over the filled area.

That's it, ready for the boating lake.

As you have read, I did this modification with the rudder already fitted on the yacht but if you have a similar rudder and want to enlarge the blade, it would be easier to carry out this procedure before fitting to the yacht.