Adding stringers to reinforce mast step and trunk.

Discussion in 'Fiberglass and Composite Boat Building' started by Canracer, Dec 2, 2014.

  1. Canracer
    Joined: Aug 2009
    Posts: 621
    Likes: 9, Points: 18, Legacy Rep: 47
    Location: Florida

    Canracer Senior Member

    Getting smarter every day. That "rail" part of a web frame is called a flange.
    [​IMG]

    Here are my flanges. cut down the center and sealed in epoxy. I thought this might be the best way to get a frame into a tight spot, but now I'm reconsidering. It's just so complex that I'm going a different direction.
    [​IMG]

    A U shaped bar makes an fantastic workbench.
    [​IMG]

    This is my first cut into a piece of marine lumber. Just in case you didn't notice I'm a new at this.
    [​IMG]

    I epoxied some ply onto the outside of the centerboard trunk. This is where the forces from the foil enter the hull.
    [​IMG]
     
  2. Canracer
    Joined: Aug 2009
    Posts: 621
    Likes: 9, Points: 18, Legacy Rep: 47
    Location: Florida

    Canracer Senior Member

    The new compression post was laminated with epoxy and micro fibers. It's 6 layers of 3/8ths inch Okume.
    [​IMG]


    The top and bottom was faired with epoxy and fumed silica.
    [​IMG]


    Four layers of 10 ounce glass went down the center.
    [​IMG]


    Seven layers of 10 ounce in the compression post area. Today, I will probably increase the amount of glass in this area and expand it out beyond the stringers.
    [​IMG]

    The plan for web frames morphed into what might be considered ring frames with knees.
    [​IMG]
     
    Last edited: Mar 23, 2015
  3. Canracer
    Joined: Aug 2009
    Posts: 621
    Likes: 9, Points: 18, Legacy Rep: 47
    Location: Florida

    Canracer Senior Member

    The compression post is finished.
    [​IMG]

    All edges have a 1/4" radius. The holes are for weight reduction.
    [​IMG]
     
  4. Canracer
    Joined: Aug 2009
    Posts: 621
    Likes: 9, Points: 18, Legacy Rep: 47
    Location: Florida

    Canracer Senior Member

    I sanded the underside of the panels cut from the cockpit sole.
    [​IMG]


    Lot's of old polyester to remove.
    [​IMG]
     
  5. Canracer
    Joined: Aug 2009
    Posts: 621
    Likes: 9, Points: 18, Legacy Rep: 47
    Location: Florida

    Canracer Senior Member

    New epoxy and some 6 ounce cloth. It's not exactly pretty but it should be strong.
    [​IMG]
     
  6. Canracer
    Joined: Aug 2009
    Posts: 621
    Likes: 9, Points: 18, Legacy Rep: 47
    Location: Florida

    Canracer Senior Member

    It was a busy day with the jig saw. I cut and fit 30 of these corner supports. Three at each corner.
    [​IMG]
     
    Last edited: Mar 28, 2015
  7. Canracer
    Joined: Aug 2009
    Posts: 621
    Likes: 9, Points: 18, Legacy Rep: 47
    Location: Florida

    Canracer Senior Member

  8. Canracer
    Joined: Aug 2009
    Posts: 621
    Likes: 9, Points: 18, Legacy Rep: 47
    Location: Florida

    Canracer Senior Member

    I added graphite powder to the epoxy and things got messy. Not easy working upside down through a small hatch. You can see the work or touch it, but you can't do both. This is the under side of the cockpit at the compression post. I have to get under there again to add some fillets but not until I buy more silica.

    Honestly, the only way to see this area is to stretch an arm through the hatch with a camera. Wow, this looks harsh. I should probably delete this picture.
    [​IMG]
     
    Last edited: Apr 5, 2015
  9. Canracer
    Joined: Aug 2009
    Posts: 621
    Likes: 9, Points: 18, Legacy Rep: 47
    Location: Florida

    Canracer Senior Member

    The compression post install is complete. I notched it's forward set of stiffeners into the stringers.
    [​IMG]

    Starboard side.
    [​IMG]

    Looking from behind the post, It's tied into the boat at the hull and at the cockpit.
    [​IMG]

    Just a bit more work to do and then the cockpit panel drops back into place.
    [​IMG]
     
  10. Canracer
    Joined: Aug 2009
    Posts: 621
    Likes: 9, Points: 18, Legacy Rep: 47
    Location: Florida

    Canracer Senior Member

    The frames are complete. Two frames are along each side of the centerboard trunk and one frame is at each side of the new compression post (foreground left.) Those corner reinforcements add up to 84 individual pieces (installed in groups of three.)
    [​IMG]


    That plate is under two frames and it supports the leading and trailing edge of the rebuilt centerboard (with increased lift.) In the full down position and also at partially down, the foil will always work against that plate.
    [​IMG]

    This frame was bowed up slightly and had to be sanded flat for a nice panel fit.
    [​IMG]

    All the gluing surfaces were wet out and then the thicker stuff was added. I'm very happy with the final fit of the panels. It feels so good to see them back in place!!!
    [​IMG]

    I knew these disk brakes would be good for something.
    [​IMG]
     
    Last edited: Apr 12, 2015
  11. Canracer
    Joined: Aug 2009
    Posts: 621
    Likes: 9, Points: 18, Legacy Rep: 47
    Location: Florida

    Canracer Senior Member

    I'm happy with this result. After a little sanding the panel was very fair.
    [​IMG]


    With a little paint or some new gel coat, the cosmetics will improve. There are lots of small epoxy spills from years of small projects. I'm happy to sail it like this for now. Some of those lines look like saw cuts but they are Sharpie marks.
    [​IMG]


    I built a lighter mast partner. Don't buy the $10 dollar hole saw kit at Harbor Freight (it's not worth it.)
    [​IMG]


    From the underside I removed a few plys with a router (I want it lighter.)
    [​IMG]


    The original teak partner and coamings aren't extremely heavy but it must be at least twice the weight of the plywood replacement (also shown is the original hatch, it's very heavy with over-sized stainless and bronze hardware.)
    [​IMG]


    I should get a nice scale and keep track of everything's weight. The Coronado 15 class has a minimum of 385 pounds.
    [​IMG]
     
    Last edited: Apr 15, 2015
  12. Canracer
    Joined: Aug 2009
    Posts: 621
    Likes: 9, Points: 18, Legacy Rep: 47
    Location: Florida

    Canracer Senior Member

    Here is my version of a light weight hatch. It's 5mm ply secured into place with tension from a bungee looped around the forward bulkhead.
    [​IMG]


    The "lower mass" partner and hatch are installed. They're sealed with West System 105/207 and then finished with Interlux Perfection Plus. I'm sailing without coamings.
    [​IMG]

    This stuff es mucho dinero.
    [​IMG]
     
    Last edited: Apr 15, 2015
  13. Canracer
    Joined: Aug 2009
    Posts: 621
    Likes: 9, Points: 18, Legacy Rep: 47
    Location: Florida

    Canracer Senior Member

    The original rudder cassette is a hefty piece of cast aluminum.
    [​IMG]


    The inner surface of one side has three high spots. I took these down with a file. If left as they were, they would wear large grooves into the head of my rebuilt rudder. They also might push the rudder off center.
    [​IMG]


    With a round file and a Dremel tool I reshaped the area aft of the bottom pintle. The casting stood proud and prevented the rudder from dropping into a full down position (creates aft rake.)
    [​IMG]
     
  14. Canracer
    Joined: Aug 2009
    Posts: 621
    Likes: 9, Points: 18, Legacy Rep: 47
    Location: Florida

    Canracer Senior Member

    Before and after style.

    Before
    [​IMG]


    After.
    [​IMG]
     

  15. Canracer
    Joined: Aug 2009
    Posts: 621
    Likes: 9, Points: 18, Legacy Rep: 47
    Location: Florida

    Canracer Senior Member

    Before(bad.)
    [​IMG]


    After (good.)
    [​IMG]
     
Loading...
Similar Threads
  1. catsketcher
    Replies:
    17
    Views:
    631
  2. Arkontis
    Replies:
    3
    Views:
    1,048
  3. burke
    Replies:
    8
    Views:
    1,977
  4. fly186
    Replies:
    10
    Views:
    1,483
  5. robwilk37
    Replies:
    3
    Views:
    1,901
  6. leaky
    Replies:
    5
    Views:
    1,758
  7. cdre
    Replies:
    10
    Views:
    4,529
  8. simon
    Replies:
    5
    Views:
    1,652
  9. Dan H
    Replies:
    6
    Views:
    1,572
  10. CapeCodAngler
    Replies:
    6
    Views:
    3,366
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.