Results 1 to 28 of 28

Thread: Damaged rudder

  1. #1
    Join Date
    Aug 2015
    Location
    Stavanger, Norway
    Posts
    116

    Default Damaged rudder

    Can this cracked rudder be repaired? The blade is made of plywood.
    20180902_201746-EFFECTS.jpg20180909_095721.jpg20180909_095712.jpg20180909_095659.jpg

  2. #2
    Join Date
    Oct 2008
    Location
    Walney, near Cumbria UK
    Posts
    40,761

    Default Re: Damaged rudder

    I would say not. What hit it? Why did it break? You dont want to copy a weakness.
    It really is quite difficult to build an ugly wooden boat.

    The power of the web: Anyone can post anything on the web
    The weakness of the web: Anyone can post anything on the web.

  3. #3
    Join Date
    Sep 2007
    Posts
    1,086

    Default Re: Damaged rudder

    +1 on Nick' s comments. I'd make a new rudder from lumber. Starting with a wide enough piece equal to the cheeks then edge nail and glue narrower pieces progressively to build the blade.

    Or on the other hand maybe you should think about a kick up rudder.
    Last edited by navydog; 09-09-2018 at 08:11 AM.

  4. #4
    Join Date
    Oct 2008
    Location
    Walney, near Cumbria UK
    Posts
    40,761

    Default Re: Damaged rudder

    I would be inclined to raise the top of the blade so that it springs from the cheeks, filling in that skinny bit and the hollow.
    It really is quite difficult to build an ugly wooden boat.

    The power of the web: Anyone can post anything on the web
    The weakness of the web: Anyone can post anything on the web.

  5. #5
    Join Date
    Mar 2001
    Location
    Grosse Pointe, Michigan, USA
    Posts
    13,866

    Default Re: Damaged rudder

    Depends on what you would consider "repaired". I could see forming a metal channel on the trailing edge that would make it functional. It also looks pretty thick to have cracked like that. Might consider some redesign.

  6. #6
    Join Date
    Sep 2007
    Posts
    1,086

    Default Re: Damaged rudder

    Looks to me as though the break was caused due to forces applied to the head of the rudder and not while the boat was in use.

  7. #7
    Join Date
    Nov 2014
    Location
    Seattle, WA
    Posts
    2,711

    Default Re: Damaged rudder

    Quote Originally Posted by navydog View Post
    Looks to me as though the break was caused due to forces applied to the head of the rudder and not while the boat was in use.
    Yep. I'm guessing that it's from a ramp strike in launching/retrieving on the trailer or impact from backing up into something. But that spot is an obvious weak point. The force on the tiller is twisting the rudder right at that top pintle, where the blade is narrowest and weakest, and made even weaker by the fastener holes. I think Nick is right - widen the blade in that area and raise the point where it extends aft from the cheeks. And then unship the rudder before retrieving the boat onto the trailer.

    Edit: It looks like there is a pintle and gudgeon above the break in the photo of the boat but it's not visible in the photo of the rudder. If that's missing then there's the problem. Tough to really tell from the photos though.
    Last edited by cstevens; 09-09-2018 at 09:34 AM.

  8. #8
    Join Date
    Jun 2003
    Location
    Central Coast, Ca
    Posts
    20,766

    Default Re: Damaged rudder

    Quote Originally Posted by cstevens View Post
    Edit: It looks like there is a pintle and gudgeon above the break in the photo of the boat but it's not visible in the photo of the rudder. If that's missing then there's the problem. Tough to really tell from the photos though.
    I think the three gudeons on the boat are holding a rod that allows the rudder to raise a bit.

    That is a classic plywood rudder (and centerboard) failure, usually having something to do with the ground while sailing.
    I would just make a new plywood rudder using 3 pair of gudeons adding one under the cheeks, and skip the raising and lowering bit.

  9. #9
    Join Date
    Nov 2014
    Location
    Seattle, WA
    Posts
    2,711

    Default Re: Damaged rudder

    Quote Originally Posted by Canoeyawl View Post
    I think the three gudeons on the boat are holding a rod that allows the rudder to raise a bit.

    That is a classic plywood rudder (and centerboard) failure, usually having something to do with the ground while sailing.
    I would just make a new plywood rudder using 3 pair of gudeons adding one under the cheeks, and skip the raising and lowering bit.
    Ah, that makes sense.

  10. #10
    Join Date
    Apr 1999
    Location
    Hyannis, MA, USA
    Posts
    45,278

    Default Re: Damaged rudder

    So much of that rudder looks like a custom set of bad ideas that I think it's great that it cannot be repaired.

    Let's start with how much deeper the rudder is than the boat's heal. Not even close to rational for a boat otherwise suitable for beaching. This is made more confusing by how high the gudgeons appear to ride on the up pointing pintles. We can see the straps for a top pintle and would expect the straps for the corresponding gudgeon to be buried under the cheeks, but shouldn't we see the gudgeon itself in that shot of the rudder leaning on the door frame. And, by the way, what's that line emerging above the middle gudgeon.

    I'd been assuming that the break was caused by the blade striking ground, bouncing out of the lower pintle, and then breaking. But I now notice navydog and cstevens making posts (#6, #7) that focus on the missing gudgeon. Likely thought.

    I don't see how a long rod connecting opposing gudgeons could work given the tiller and space available and even if it did, a good grounding would let the rudder slide up and the upper rudder-attached gudgeon would slip off, leading to the strains that broke things in the first place.

    If the designer is available, ask about some changes.

    If you must keep that shape, you'll want to custom make the pintles. Just two. The upper should be as long as the rudder drips below the heel of the boat plus and inch. It's upfacing pin should end at about the height of the horn. The lower pintle should be at least an inch longer so you can get the lower gudgeon slotted before you do the upper. I think this will put the upper gudgeon up under the cheek pieces, about halfway down from under the tiller to the bottom of the cheeks. That's fine. You can either have different straps to get outside the cheeks or you can let the straps into the cheeks, which is not quite as strong but might be adequate.

    This gives plenty of travel but depending on how you take the ground could lead to bent pintles. Many larger boats simply have two gudgeons far enough apart for the rudder to rise out of trouble and connected by a bolt that captures the rudder's gudgeon. This pic show the test fit of Meg's rudder. You can see Dave's hand aiming the bolt while Drew wiggles the rudder. The upper gudgeons work the same way. A light version might suit you.



    Or be bold, flatten the bottom of the rudder so the skeg takes the ground, maybe stretch the rudder blade back a bit. I'd not put an end plate on because at that angle it would act as a brake.

    G'luck

  11. #11
    Join Date
    May 2012
    Location
    UK. Cornwall, Suffolk.
    Posts
    4,346

    Default Re: Damaged rudder

    Quote Originally Posted by kleppar View Post
    Can this cracked rudder be repaired? The blade is made of plywood.
    20180902_201746-EFFECTS.jpg
    Not a terribly good fit with the hull is it?

    I'd like to see the bottom of the leading edge go down to the bottom of the stern post, and the horizontal lines approach horizontal..at least the top edge if you want it to extend below the keel. Looks a bit afterthought-ish to my eye.

  12. #12
    Join Date
    Jan 2004
    Location
    Norwich,United Kingdom
    Posts
    5,598

    Default Re: Damaged rudder

    Not a good plan to have doublers that finish just above the narrowest point of a plywood rudder.Couple with an outline that could hardly have a better example of a stress raiser;you were on borrowed time.Were it my boat I would build a replacement with a pivoting rudder blade and extend the plywood doublers to a little above the waterline to form a rudder stock.I wouldn't be too concerned about the rudder projecting well below the keel if it could be lifted in shallow water and I definitely wouldn't use plywood for a new rudder blade-it can and does break.For peace of mind I would also use a Clamcleat CL257 to keep the blade down and yet have the assurance that an impact would allow the rudder blade to swing up.

  13. #13
    Join Date
    Oct 2009
    Location
    South Puget Sound/summer Eastern carib./winter
    Posts
    15,032

    Default Re: Damaged rudder

    Junky engineering. Tear along the dotted line.
    Among other things,make the cheeks deeper, and taper them out.

  14. #14
    Join Date
    Jul 2017
    Location
    Toodyay, Western Australia
    Posts
    631

    Default Re: Damaged rudder

    I agree with the comments above regarding the engineering and shape, but I would have to disagree that the rudder can not be repaired. If the cheeks were extended far enough that would effectively form a big butt block on both sides of the break. That alone would make the rudder functional again, but there is plenty more could be done to make it stronger. So, not so much a question of repairability as a question of whether it is easier to modify what you have or easier to start afresh. Maybe depends on resources available.

  15. #15
    Join Date
    Aug 2015
    Location
    Stavanger, Norway
    Posts
    116

    Default Re: Damaged rudder

    The boat hit the fence (you can see at the boatīs rear end). My own stupidity to thank!

  16. #16
    Join Date
    Aug 2015
    Location
    Stavanger, Norway
    Posts
    116

    Default Re: Damaged rudder

    The boat hit the fence (you can see at the boatīs rear end). My own stupidity to thank!
    Attached Images Attached Images

  17. #17
    Join Date
    Aug 2015
    Location
    Stavanger, Norway
    Posts
    116

    Default Re: Damaged rudder

    Sorry for not knowing all the expert words - gudgeons, cheek and what not - as you may have surmised, I am not a native speaker, and certainly not of maritime terms...Would it be possible to glue it together with a healty amount of epoxy, and the later on, work on a better desiged rudder?

    Maybe the easiest is to use the original cheeks (made of hard wood), remove and replace the damaged plywood blade, keep all original metal fittings.

    For you interest, the boat is a Storm 19, built by Swallowyachts in Wales (former Swallowboats). I bought it new in 2005.

    Should I ask Swallowboats for an improved design?
    Last edited by kleppar; 09-10-2018 at 02:31 PM.

  18. #18
    Join Date
    Oct 2008
    Location
    Walney, near Cumbria UK
    Posts
    40,761

    Default Re: Damaged rudder

    Quote Originally Posted by kleppar View Post
    The boat hit the fence (you can see at the boatīs rear end). My own stupidity to thank!
    Quote Originally Posted by kleppar View Post
    Sorry for not knowing all the expert words - gudgeons, cheek and what not - as you may have surmised, I am not a native speaker, and certainly not of maritime terms...Would it be possible to glue it together with a healty amount of epoxy, and the later on, work on a better desiged rudder?

    Maybe the easiest is to use the original cheeks (made of hard wood), remove and replace the damaged plywood blade, keep all original metal fittings.

    For you interest, the boat is a Storm 19, built by Swallowyachts in Wales (former Swallowboats). I bought it new in 2005.

    Should I ask Swallowboats for an improved design?
    OK, that explains a lot.
    That will not fix with glue. Salvage the cheeks and fittings and replace the blade, but for strength bring the top edge straight out from above where the cheeks start to curve forward.
    It really is quite difficult to build an ugly wooden boat.

    The power of the web: Anyone can post anything on the web
    The weakness of the web: Anyone can post anything on the web.

  19. #19
    Join Date
    Apr 1999
    Location
    Hyannis, MA, USA
    Posts
    45,278

    Default Re: Damaged rudder

    The pic in #16 clarifies a great deal. The structural problem is that the upper gudgeon is installed on the rudder below the cheeks. That can impose a concentrated strain right where it did break. I'm thinking that the strain is probably not too critical when sailing but other accidents can happen especially when running aground. I doubt that you can make a new structure that can withstand a backing accident.

    It looks to me that the placement of the gudgeons and how they slide was well thought out and should not be changed.

    I'm not sure where the water line is. And I can't tell if the cheeks are simply glue laminated on or screwed in place.

    I would rebuild the whole unit with longer cheeks, coming down maybe 7 to 8 cm lower than it does not. Make closely fitted slots in the cheeks to allow for the tangs and through-bolt. If you have access to bronze rod it might be very nice to bore a snug hole through some copper coins and make three rivets.

    The angle that the cheeks make now seems good. You could make the lowest part of the new cheeks in such a place that as they sweep back they end just about where the rudder blade arcs out. That might be below your load waterline and might make a fatter structure than the horn (that timber that makes your stern stem). If so, just bevel the front of the cheeks so they achieve full thickness where the forward most bolt is and maybe taper the trailing edge of the cheeks a bit.

    If you really want to get sailing again fast, you could through-bolt two pairs of mending plates - any bronze strapping will do - after injecting as much epoxy as you can manage. But plan on a new rudder and longer cheeks.

    G'luck

  20. #20
    Join Date
    Aug 2015
    Location
    Stavanger, Norway
    Posts
    116

    Default Re: Damaged rudder

    Cheeks are glued.

  21. #21
    Join Date
    Jan 2010
    Location
    Northern Europe
    Posts
    9,232

    Default Re: Damaged rudder

    You could remove the pintel and hollow out half the thickness with a grinder, and fill with glass fibres and epoxy finished with some cloth, carbon if you want strength without the thickness, then turn it over and do the same on the other side. The "in-line" screws on plywood are often a weakness.

  22. #22
    Join Date
    Oct 2008
    Location
    Walney, near Cumbria UK
    Posts
    40,761

    Default Re: Damaged rudder

    Do not forget, if you do a "quick fix" to get you sailing this season, it will still be there when you sell the boat or it breaks again.
    It really is quite difficult to build an ugly wooden boat.

    The power of the web: Anyone can post anything on the web
    The weakness of the web: Anyone can post anything on the web.

  23. #23
    Join Date
    Jul 2017
    Location
    Toodyay, Western Australia
    Posts
    631

    Default Re: Damaged rudder

    +1 for skaraborgcraft's solution. A variation on the idea would be to scarf fresh material both sides, glue in with thickened epoxy, and glass over both sides... probably end up stronger than the original. Scarf joins of this type take some patience but can be achieved with simple tools. I've done a few with chisels.

  24. #24
    Join Date
    Aug 2015
    Location
    Stavanger, Norway
    Posts
    116

    Default Re: Damaged rudder

    Thanks to all of you for all ideas - repairs, new rudder, design and what not. This is a marvellous forum!

  25. #25
    Join Date
    Apr 2015
    Location
    St. Helens, Oregon
    Posts
    1,151

    Default Re: Damaged rudder

    That's a beautiful boat, by the way, rudder issues notwithstanding I'd do skaraborgcraft's repair and work on a new rudder incorporating some of the other concepts over the winter. And you might contact Swallowyachts...they may have an improved rudder by now.

  26. #26
    Join Date
    Aug 2015
    Location
    Stavanger, Norway
    Posts
    116

    Default Re: Damaged rudder

    I think I shall settle for this to start with!

  27. #27
    Join Date
    Aug 2015
    Location
    Stavanger, Norway
    Posts
    116

    Default Re: Damaged rudder

    Have already contacted Swallowyachts - waiting on reply. I am also the owner of a Vivier Jewell. I have been considering selling my Storm 19, but I am fond of it, having owned it for more than ten years.....

  28. #28
    Join Date
    Jul 2017
    Location
    Toodyay, Western Australia
    Posts
    631

    Default Re: Damaged rudder

    Quite a collection. Glad I'm not the only one with too many boats. At least you have alternatives to get on the water while you work on the rudder.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •