How to fix gap in side of fiberglass hull

Discussion in 'Fiberglass and Composite Boat Building' started by aaronhl, Apr 15, 2025.

  1. aaronhl
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    aaronhl Senior Member

    I was planning to cover the outside of the hull opening with them and then start putting resin and chopped down

    Or should I use wide masking tape instead?

    Need something to follow the curves of the hull and make the outside repair a little easier
     
  2. aaronhl
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    aaronhl Senior Member

    Yes I can use plywood for the larger area, and could put the lamination sheets over the plywood...for the curved areas like the rub rail I couldn't use plywood, rather just masking tape or the stick on lamination sheets?
     
  3. wet feet
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    wet feet Senior Member

  4. aaronhl
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    aaronhl Senior Member

    I am going to try putting some resin as a test on one of the cheap sheets - Otherwise I can use masking tape for the cuves and plywood coated with PVA - Even though I plan to also repair from outside once I get the inside repaired, I do not want to have a lot of bulges or gaps showing on the outside once I get the inside repaired

    Good news is I was able to "bend the hull" so the gap is closed and lined up very nicely - I used some long rules and levels along the bottom but I am lucky there was a sliver left of the gray striping to reference !

    I realize I cant just put fiberglass over the cracks, but I am glad the pieces are true to where they need to be so I can start to grind tapers

    [​IMG]

    [​IMG]
     
  5. aaronhl
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    aaronhl Senior Member

    Looking at it again most of the areas are flat so I probably could use masking tape for all the curved "edges" only and then cut different size plywood covered with pva for all the "flat" sections
     
  6. ondarvr
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    ondarvr Senior Member

    Regular packing tape works if thats the way you want to go. But tape doesn't allow you line up the outside if the surfaces aren't in alignment.
     
  7. aaronhl
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    aaronhl Senior Member

    So i dove right into this last night instead of continuing to ruminate on ways to do it. working with a long ruler I found I am going to need to use plywood and self taping screws on the outside of the hull, before starting to fiberglass from the inside. Even the large flat section, it looks flat but but with a long ruler it's not. Ill use a larger piece of plywood to ensure the two pieces are flush. I was not able to start it as one complete repair, I wanted to to get most of the two sections lined up first as I need to move it in a couple directions... I will now start to work on the flat parts

    With how rough the original gelcoat and fiberglass edges are a repair from outside as last step to put down chopped and then fair the gelcoat is okay with me...and then I get support from inside and out anyway

    At least it's a start and I am doing it Aaron's way so forgive me if it is not perfect

    [​IMG]

    [​IMG]
     
  8. ondarvr
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    ondarvr Senior Member

    That is what everyone has been saying all along. The only difference in methods is in pre-gel coating what will end up being the outside finished surface of the hull.

    I don't put much value in it because that surface typically ends up needing a good deal of work in getting it faired after all the glass work is done. So I tend to not do it most of the time. Neither method is right or wrong, they both sort of end up in the same place at the end of the project.

    If you live in country where gel coat is traditionally not sprayed, and gel coats aren't formulated to be sprayed, you develop methods that don't involve it beng sprayed. In the US virtually all of the gel coat being sold is formulated to be sprayed, so repair methods take that into account.
     
  9. aaronhl
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    aaronhl Senior Member

    Ok Sounds sounds like I am doing okay, didn't really want a bunch of screw holes all over but I guess that easy fix rather than the panels not lining up together
     
  10. aaronhl
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    aaronhl Senior Member

    What are your thought of a heavy amount of chopped pieces mixed with thickened resin for the "minimal" outside repair, rather than matt and resin? Before gelcoat and polishing
     
  11. ondarvr
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    ondarvr Senior Member

    Why, it's easier to use mat and it will be significantly stronger.
     
    Last edited: Apr 28, 2025
  12. aaronhl
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    aaronhl Senior Member

    Well I was wondering on the strength different because I feel the thickened resin would be easier to work with, less drips and you dont have to cut the matt to size, you kinda just spread the thickened (with chopped added) resin in the grinded out void, just shy of the gelcoat, no matt loose ends to trim or get on the original gelcoat area if you get what i mean
     
  13. BlueBell
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    BlueBell . . . _ _ _ . . . _ _ _

    Aaronhl,

    What was the cause of this damage?
    I believe there may be more damage than what appears.
    You're going to need to expose more than you have in your repair thus far.
    Are there cracks on the other side of the hull as well?
    What happened, did it fall off a trailer, was it dropped during a lift?
    What was the cause of this damage.

    BB
     
  14. aaronhl
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    aaronhl Senior Member

    The previous owner said he hit a huge wave
    I looked around ...no other damage on bottom section of hull, only the rear deck/outboard engine splash well
    Will be fiber glassing the hole in the side then adding new core before fiber glassing the top deck back on...
    Not trying to make it any more difficult because I do not believe in it having other damage
     
  15. ondarvr
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    ondarvr Senior Member

    Thickened resin isn't nearly as strong, and it will take virtually the same amount of time effort and money to use use mat.
     

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