Radon extension and rebuild project

Discussion in 'Powerboats' started by Bigtalljv, Feb 15, 2022.

  1. Bigtalljv
    Joined: Aug 2019
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    Location: California

    Bigtalljv Junior Member

    I started working on my old radon and thought it would be best to have a single place for all my questions. I had started a couple threads about the extension options and some stringers over balsa.

    so here the story. This is a mid-70s 24’ Radon. Radon’s are a local Santa Barbra designed commercial boat originally for urchin divers. The original family run business is still in Santa Barbra, my boat was built in Oregon by one of the employees who started a business up there with licensed molds from Radon. Radon boats are very much a local thing, people in Southern California love them. They are trucks and built that way. Designed mostly to haul large loads of urchins home from the Channel Islands to the mainland. They excel in a following sea as that is what the prevailing swell always gives you here for the trip home. This boat had been worked on by a couple guys who we’re going to commercial dive it hence the low gunnels. They had a new fuel tank (which I’ll remove) and a bunch of glass work done professionally on the pilot house and a good chunk of the topsides, then they drilled holes in all that to mount stuff, didn’t seal it, and left it out in the rain for 10 years. Needless to say there is a bunch of wet plywood in there now. I need to remove, relocate, and replace most of the bulkheads for the new layout. I have design dimensions from several other boats that were professionally rebuilt so I have those rough dimensions to go off of. I don’t unfortunately have layup schedules or anything.

    I’ll be extending it 3.5’ and hanging outboards off it eventually. I’ll also be extending the cabin so there is room for a small table and benches and reworking the the cuddy.

    I have started the demo for the hull extension by cutting out the existing transom skin and removing a couple feet of the stringers past the limber holes and old engine mount holes. The transom and rear parts of the stringers were very wet.

    And the biggest reason I am doing this? I’m 6’7” so I don’t fit into any production cabin boat that I can afford. I didnt want to spend $10’s of $Ks on a production boat to hack a taller cabin into it. so that’s a quick synopsis of my crazy/stupid idea to rebuild a boat. I hope you all understand.

    jason
     

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    bajansailor likes this.
  2. kapnD
    Joined: Jan 2003
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    Location: hawaii, usa

    kapnD Senior Member

    Only one type of laminate peels up like that, and that is chopper gun slop.
    I’d like to see a real hi definition close up shot of the hull layup where it’s been cut through.
     
  3. Bigtalljv
    Joined: Aug 2019
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    Location: California

    Bigtalljv Junior Member

    So I was kind of wondering if there was a way to tell when I needed to stop tearing layers off the hull?

    And you can see the last bit of the old transom, does that stay or go? I was going to grind back at an angle, 12:1(?) and overlap the new layers at least that much, maybe a couple feet just because….
     

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  4. kapnD
    Joined: Jan 2003
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    Location: hawaii, usa

    kapnD Senior Member

    Looking at the visible edge of the laminate, it looks like the entire layup may have been done with chop, with some woven roving between layers, but not very well saturated or rolled out.
    You’ve got to grind down to reasonably strong, dense laminate in order to expect any new lamination to be well bonded.
    The long angle requirement allows lamination to bond to each layer of the old laminate, however your stringers and bulkheads will have to rely on surface bond alone.
    I’d be using a very generous overlap on all tabbing that contacts the hull.
     
  5. Bigtalljv
    Joined: Aug 2019
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    Location: California

    Bigtalljv Junior Member

    Thanks. I think the base layers they laid in the mold first are just roving, I dug down a little far and hit solid roving. I believe they used chop strand and more roving when they put in the stringers and the balsa padding. As I said I dug down a little far so I’m going to have to build a little of the hull from the more solid roving up.
     
  6. socalspearit
    Joined: Apr 2021
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    Location: Los Angeles, CA

    socalspearit Junior Member

    My slip neighbors (out of Los Angeles) who is a small commercial lobster fishermen has one of the very first Radon's. It looks like a 50 year old commercial boat that's for sure but thing is solid and still making its owner money. He said he recently had to drill through the hull; it's still bone dry 3/4 wood in there. Next time I am at the harbor I'll take a photo of the boat.
     
  7. Bigtalljv
    Joined: Aug 2019
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    Location: California

    Bigtalljv Junior Member

    Nice! Sounds like it’s a 60’s boat. They went from glass over play to molded glass hulls in the early 70’s. That’s a classic.
    Jason
     
  8. Bigtalljv
    Joined: Aug 2019
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    Location: California

    Bigtalljv Junior Member

    Well I’m “progressing “ slowly. I have one side of the mold assembled but I’m struggling with the hull shape and angles, they don't seem to quite line up. There’s a flat pad (lifting pad?) in the bottom of the aft keel that is confusing me. I know nothing is “straight” on a hull but this is giving me a headache :)
    Here you can see the angle.
    63A78E24-716D-4BBA-BCAA-0413D6FE02CD.jpeg
    this is what it looks like if I put the straight edge on the up angle flat next to the pad
    39A958E8-F4A9-4BC5-BAC3-603CDD246019.jpeg
    This is the angle if I put the straight edge along the angle of the pad. Is the hull flattening out as it moves aft?

    Or it just dawned on me that I cut the center section square and perhaps it need to be a wedge? As I go aft the center section needs to get wider? Thats actually how it is now.

    E60D73DA-1DED-47AC-B27A-E48CA2A645AE.jpeg

    63A78E24-716D-4BBA-BCAA-0413D6FE02CD.jpeg 39A958E8-F4A9-4BC5-BAC3-603CDD246019.jpeg DDC9F8A9-2CB8-4129-A238-20F70FFC92CE.jpeg E60D73DA-1DED-47AC-B27A-E48CA2A645AE.jpeg
    DDC9F8A9-2CB8-4129-A238-20F70FFC92CE.jpeg
     

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  9. comfisherman
    Joined: Apr 2009
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    Location: Alaska

    comfisherman Senior Member

    There is a big SA fellow wandering around California (or there used to be) who stretched a few of the 32 Radons for a film crew and a couple of urchin divers. Only person I've met who admitted to stretching more than one....

    See if I can dig up his info in the way back machine of old phones. Probably the only resource that could answer definitively on the best course of action.
     
  10. Bigtalljv
    Joined: Aug 2019
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    Location: California

    Bigtalljv Junior Member

    Thanks, I’m always happy to get more information. I’m actually making progress. I think I understand more about the sale of the hull and I figured out a big mistake. I’m sure there are proper names for all of it but there is a center flat spot on the bottom of the hull that is triangular. That section rises as it goes aft. The flats in either side are level. I originally cut a center section that was straight and nothing lined up. Once I realized I needed to continue that triangle it all fit together perfectly!

    6027E4B9-32CC-47E7-92C2-794F67204622.jpeg
     
  11. Bigtalljv
    Joined: Aug 2019
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    Location: California

    Bigtalljv Junior Member

    Well I’ve only pulled it apart like 6 times but I think I have it. Square to within 1/16” over 98”, is that acceptable? I can see actually laying glass is going to be super fun, that’s really big. EC926DA3-7A6B-4D4D-AD33-36BE7403EEAA.jpeg
     
  12. comfisherman
    Joined: Apr 2009
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    Location: Alaska

    comfisherman Senior Member

    If your 1/16th your better than 95% of the glass boats running around my neck of the woods....

    Last hull I fit out when playing with my lasers looked like it was built by the Steve Buscemi meme and there are about 45 of those rocking the waters of Alaska. I'd say your good!
     
  13. Bigtalljv
    Joined: Aug 2019
    Posts: 52
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    Location: California

    Bigtalljv Junior Member

    Alright, so I’m thinking about getting some glass out down. I mean I still have to secure the mold, fillets, wax/pva, etc but glass is coming! (Someday)

    questions about that. What’s the best way to handle seams in the cloth sections? Obviously the new section is 3’x8’ so one price if cloth isn't going to cover it all, I will have to have multiple adjoining pieces. Do I butt the pieces together or overlap them? I would imagine that I want to space seams out as much as possible and even change the direction on subsequent layers?

    corners, glassing corners to this extent is new to me. How do I handle that? Depending on the way it lays I foresee some excess material in the corners. I also think I probably want to make different layers so I don’t end up with seams all in the corners.

    I could post some pictures of what I’m thinking if any of the above didn’t make sense.

    Thanks
    Jason
     
  14. Bigtalljv
    Joined: Aug 2019
    Posts: 52
    Likes: 9, Points: 8
    Location: California

    Bigtalljv Junior Member

    Well I guess my first attempt at wet vacuum bagging is an ongoing success. It’s quite the difficult panicked dance to get it sealed up. If I keep the pump running I can get -25 .in Hg, which I think is plenty, hopefully not too much. I have some leaks I can’t track down….
     

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  15. Bigtalljv
    Joined: Aug 2019
    Posts: 52
    Likes: 9, Points: 8
    Location: California

    Bigtalljv Junior Member

    Well, the expected unexpected happened, I had a mechanical vacuum pump failure. Looks like I’m gonna get some more grinding practice….
     

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