Well sometimes you just need a little home grown ingenuity some spit and glue and a grinder or 2.
Take one replacement rudder, grind the shaft down to M8 from M10 then linish for a smooth finish.
Square of the top of the shaft to fit the steering cable system plate and drill for a split pin.
Add some roofing seals and thrust washer to keep the sand etc out and the assembly moving smoothly.
Inset a split pin to keep the whole thing in place.
Tension cables to suit.
Hay presto K15 with working rudder.
Launching of the beast tomorrow morning in the river.
hey phil nice job. watch that spilt pin with those sharp edges. maybe turn them down. step or land on those and it could be nasty
Great point Mr Lacey
just turned them under.
I might also put grip over the whole set up.
Have you ever tried a small fixed fin at the very back with the small rudder slightly forward as the K15 rudder is say 3ft from the stern fin?
Or do you need to only use the rudder and nothing else?
Phill
just turned them under.
Lacey I dont think many of them have had the rudder fitted?
So just having a play around to see how it will go with the rudder.
I indent to try a very narrow fixed fin right at the stern with the rudder 3ft forward
Well the rudder works pretty well in fact it turns the board in about a board length and a half hard over. The rudder alone does cause the board to be less directional and slightly less stable.
I think the rudder I have is too shallow in depth and too much rake but hey always a great learning curve.
I tried a very small vertical fin in the rear fin box which improved the directional capability and this reduced the rudder effect significantly as you would expect.
I believe it would be better to get the fixed fin in the center box and then the rudder behind it so thats the next step but its a lot of fun just playing around with it.
I also tried it out with just a fluid foils spitfire fin and its as stable as all get out and directionally solid as a rock.
Phill
Inserted a short ventral fin into the centre board box and hay presto board tracks straight even in 20kn cross wind and 180 deg turns in a little more than a board length with the rudder hard over.
positioning: of rudder and ventral fin
Close up:
Revised carbon fibre rudder
After seeing my posts on the K15 DJ rang me and told me he found a carbon fibre fin in the water one day and kept it. He said it looked like it was off a clubbie ski and I could have it. I machined a new SS shaft used some high strength epoxy and hey presto much more efficient larger area rudder.
Thanks DJ
Trying it out offshore tomoz.
