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Hi Warren631!

Post by warren631 » Fri Feb 25, 2022 12:37 am

I'm thinking of shortening my HDPE custom rudder by cutting 26" off the bottom and attaching this 26" x 12" piece across the bottom using HDPE epoxy and SS screws as indicated in attached sketch so 20" is behind and 6" is in front of the pivot axis giving a balance of 30%. The square inches in the water would be the same but the depth would be 26" less.

That is a good idea to regain some of the rudder control wetted area….
Might it be suggested that one might want to initially make it adjustable to move it fore/aft to balance the rudder forces.
You probably already know this but, If the addition is too far forward of the pivot it will tend to over steer getting progressively worse as the turn increases. Similarly if too far aft the force to turn becomes progressively harder.

Your sketch has increases both fore and aft of the pivot axis.
Might it be suggested to approach this at least initially to locate the added piece proportionally similar to the original design rudder?
If the original had say 15% of its area ahead of the pivot axis to then position 15% of the added section ahead of the pivot axis.
Just a suggestion.
Your boat, your rules.

Best Regards
Over Easy

Thanks OverEasy. Good suggestions. I will try to get the balance the same as before. But I don't know how to make it easily adjustable fore/aft and still have it attached strongly. I will just have to make my best guess and fix it at that. I would have to take off the rudder to readjust it. Maybe I
will not use epoxy at first but just plenty of 1" SS screws so I could readjust it if absolutely necessary. Thanks for your interest and comments.

Hi Warren631!

Maybe start with just 2 through holes fore/aft to insert a pair of bolts?
That way you could add holes as/if you feel you need them?

Just a thought…

Best Regards
Over Easy

Here,s a mod someone done to his they made new rudders & brkt,s & made the rudders raise vertically would thisnot b a better way to go ?


I,d maybe like to do this mod myself & maybe move the rudders to a 15degree outward angle !

J

Hi Highlander!
That’s an interesting mod!
Looks like it could be replicated fairly easily too.
One drawback might be the loss of the “kick-up” capability of the current rudder system……maybe a hybrid system where the vertical slide assembly is mated to the existing kick-up bracket pivots? Some clearance issues (for when the rudder tries to kick-up when the rudder is only partially inserted) would need to be sorted out……but all the same a nice idea to address shallow water sailing while still retaining the deep water capabilities!

Best Regards
Over Easy

My cousin’s Farrier tri has a rudder bracket that functions very similar to highlander’s post photo. The main difference being that the rudder can shear a few fasteners and exit the bracket if it strikes something. There is a lanyard that keeps the blade attached to the boat. You can reinsert the rudder in the bracket to get home as long as you take it easy, if I recall correctly, as the bracket is somewhat matched to the rudder foil shape. The bracket is stretched open slightly if the blade exits to the rear.

It seems to be a far superior design compared to the pivoting design. However, the price of the bracket assembly and rudder blade is significantly higher than our stuff.

Here are photos of my modified HDPE rudder in it's up and down positions. For very shallow water. It's pretty heavy so I don't think I will need a tie-down line but can be added. It just kicks up and falls down again by weight Patent pending.

DOWN:


UP:


It has a 6" x 20" balance and same wetted area as the original vertical rudder. Cost me about US$125 for materials.

Very interested to hear how this works. Please update us when you try it out.

Hi Warren631!

Looks great!
Like the leading edge radius!
Should make it easier to lift up and over anything it might contact! Nice!
The weight should also help make it self RE-setting too!

Best Regards
Over Easy