building a new rudder for W32

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  • November 29, 2011 4:07 PM
    Message # 762305
    Deleted user

    My winter project is to build a new (improved) rudder for Neverland. After one good season with the old repaired rudder, water found it's way inside this spring after launching and activated some uncured foam causing the rudder to split open. In the past this happened over the winter when water trapped inside froze, expanded and split the rudder.

    Split rudder last spring...and quick repair in the slings...                                               

     

    My plan is to laminate a few pieces of 1/2" marine plywood together, same profile shape, but thinner and tapered to about 1/4", then covered with fiberglass. Instead of being 3 1/2" thick, it will be about 1 1/2" (pintles are 1 1/4" dia) where it meets the rear of the boat. I plan to use silicon bronze straps (1/4"x1") to attach rudder to bronze pintles, using the same fiberglass gudgeons.

    Is there anyone out there that has built a new/redisigned rudder on a W32? Any advise from experience or photos of rudder modifications would be welcome.

    Last modified: November 29, 2011 4:15 PM | Deleted user
  • November 30, 2011 7:50 AM
    Reply # 762721 on 762305
    David, do you plan to use two 1/4"x1" bronze straps for each bronze pin, one on top and one below? The original stainless G&P on my boat were 1/4"x 2" but bronze is not as strong as stainless... maybe go 3/8" on the bronze flat bar?
    What about fairing in the gudgeons at the same time? This would mean your rudder could be a bit thicker if needed.
    The laminated plywood would be a lot lighter than my rudder which must weigh about 200lbs
  • November 30, 2011 11:22 AM
    Reply # 762887 on 762305
    Deleted user

    Hi Gary, yes, will use two straps on each pintle pin, one above and below each gudgeon, so six sets of straps. Each pin has a pair of holes, exactly 2" apart, above and below each gudgeon, so a 2" strap wouldn't work on the old pins. I'm planning to use high silicon bronze (has no zinc) flat bar from Atlas Metals. If they had 2 1/2" flat bar, I would have gone for that. They seem to be the best or only source that I could find for high silicon bronze flat bar, which I think is also known as everdur, in that it doesn't have zinc in the formula. I'm assuming the pintle pins are of the same stuff, so no electrolysis worries.

    You must have the older style/shaped rudder? Which you modified? Was it you that recently did the Dave King modifications?

    According to Bud, the newer style rudder weighed about 70lbs dry.  I would guess the old style would be about the same assuming similar construction--fiberglass/foam core. The SS bracket and rudder cheeks assembly on mine wieghed about 28lbs.  My rudder also weighed about 200lbs when the foam core was waterlogged--difficult for two men two wrestle around. After I removed the waterlogged spongy foam I could lift the rudder myself.

    I plan to make the new rudder a little wider (1 3/4") than the pintle pins (1 1/4") so I can recess the straps flush into the rudder.

     

     

  • November 30, 2011 7:46 PM
    Reply # 763186 on 762305
    Yes we did the aperture and fairing mods. If you do this you will see that the width at the rear of the hull gets to be pretty substantial resulting in a wide area for the rudder (this is because of the thickness of the gudgeons on the hull)
    We did not modify the rudder shape but the older rudders are MUCH heavier (partly due to being mostly filled with mishmash - not foam)   I think the newer rudder is a much better design.

    David, I don't think the plywood will be "stiff" enough for a rudder. I think it will flex at the top. Also, you might think about putting some washers under the top straps so that the straps don't eat the glass gudgeons.

    I tried to find a rudder off a scrap boat but ran out of time. They are out there, there was one on the east coast that was being scrapped out some time ago.

  • November 30, 2011 9:11 PM
    Reply # 763250 on 762305
    Anonymous
    I have a brand new rudder built with core cell, using air vacuum bagging technic. Foil, leadind and trailing edge and apature have been enhanced see pictures its during the process just after lamination.... the part for the pins have been modified from the original design.. I have two long stainless pins same diameter as original, and they need to be insert by the bottom of the rudder .. see picture it will help to understand. It may seem hard to insert but its very easy... 

    Step 1:  3 layers of core cell have been laminated together to get the good tickness of the rudder
    Step 2 using  CNC machine the shape and foil and been cut
    Step 3 A long tube have been fix with epoxy and fiberglass all along the leading edge... 
    ... also 1 inch holes have been drilled and filled with epoxy where the stainless plate will be fix (at the top of the rudder)
    Step 4  Weight have been add at the bottom of the rudder
    Step 5 Time to laminate...
    Step 6 after lamination cut the extra part of the tube.. ie: apature etc..
    Step 7 sanding... sanding...sanding..
    Step 8 top part of the rudder will be painted with interlux toplac  and interprotect for the bottom

    You can Contact me to my personnal email.  Thanks!  

    Last modified: May 18, 2012 1:34 PM | Anonymous member (Administrator)
  • December 01, 2011 12:57 PM
    Reply # 763804 on 762305
    Deleted user

    Gary: I plan to gradually increase thickness above the waterline to match the 3 1/2" thickness of the original so as to re-use the SS bracket and cheeks. Just the "blade" below the waterline will be thinner than the original, about 1/2" thicker than the 1 1/4" pintles. Three layers of 1/2" marine ply glued together and covered with fiberglass should be strong enough, I think.

    Since I have a disfunctional rudder I'm more inclined to build a new rudder rather than the DaveKingMods as I consider the problem is not that the rear of the boat was too thin, but that the revamped rudder was too fat, along with the other rudder design issues like water absorbing foam and the workboat-like attachment, strong, but not elegant.

    I think Francois has come up with a very nice solution for attaching the rudder to pintle pins.

    Francois: Thanks for the photos. So, you must need about 2 1/2ft under the rudder to insert the pins and how are you fixing them in place? What did you use for the tube? Is your rudder about the same thickness as the original?

    Last modified: December 01, 2011 1:03 PM | Deleted user
  • December 01, 2011 3:02 PM
    Reply # 763889 on 762305
    Deleted user

    Out of curiosity, anyone know when Westsail redesigned the rudder? Year or hull #? Was it a Crealock design change?

    Seems I've seen photos of some boats with the "new" (square bottom) rudder, but not the glass gudgeons--a transition period?...or retrofited older boats? 

    I suppose this question should be in Bud's column, but maybe he's watching and will chime in with some wisdom and advice.

  • December 01, 2011 3:31 PM
    Reply # 763911 on 762305
    Deleted user
    Last modified: December 01, 2011 6:35 PM | Anonymous member (Administrator)
  • December 02, 2011 3:11 PM
    Reply # 764703 on 763911
    Anonymous
    Yes the rudder is the same tickness as my previous rudder except above the waterline.. my old rudder was a bit thinner at the topt and decided to keep the same tickness everywhere. My stainless pins have been insert before instalation of the rudder on the boat.. Of course if I want to remove the rudder I will need 2 feets below the rudder to remove the pin... Right now the pins are only insert in the tube.. and 5/8 screw can be screwed at the end on each pins ... I will eventually post of picture.. this is to help me to remove to pins eventually.. The tube that have been used is a G10 tube.... You can google it.... I still have 6 feet of stainless for the pins.. same diameter as original bronze pins.

    François
  • December 03, 2011 7:30 AM
    Reply # 765097 on 763911
    Anonymous member (Administrator)
    Norm Rhines wrote:I hope these links get you to the
     photos.

    and


    Looks nice!

    Here are the images above.
     

    Looks good

    I've thought about tapering the leading edge of Pygmalions rudder next time she is in the yard - short of the full Dave King hull modifications...

     

    Last modified: December 03, 2011 7:33 AM | Anonymous member (Administrator)
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