How Do I Move My Half Hulls Around??

Discussion in 'Boatbuilding' started by CatBuilder, Jan 1, 2011.

  1. CatBuilder

    CatBuilder Previous Member

    Ok, I just realized I overlooked one thing in my logistics.

    I have half hulls in molds to move. I had thought I'd use an engine hoist since I built the mold nice and close to the ground, but I forgot one thing!!

    I have TWO STACKED half hulls to move at times like this!

    [​IMG]

    DAMN! Forgot that part!

    Now I have to figure out another way to move the hulls around my shop. I need to be able to take them out of the female mold and move them to the other side of the shop while I build other half hulls. Something like the following would work:

    [​IMG]

    BUT... I am in a TENT like this!

    [​IMG]

    Pretty upset right now because I'm right back where I started! I thought I'd do a male mold to avoid all this bullsh*t, but then decided a female mold would be great because it's easier to glass - with the half hulls moved around by engine hoists. Now I have to deal with it all over again. :mad:

    Any thoughts on how I can move half hulls around the shop?
     

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  2. CatBuilder

    CatBuilder Previous Member

    Nevermind this thread. A genius on my cruising forum came up with the solution.

    Just cut some of the mold away at the end to slide the whole hulls out horizontally. The hulls are joined at the end of the mold's useful life, so you are throwing it out anyway. Just start cutting stuff.
     
  3. hoytedow
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    hoytedow Carbon Based Life Form

    I'm glad you found the solution. I was stumped for an idea in such a small space. :)
     
  4. CatBuilder

    CatBuilder Previous Member

    Thanks, Hoyt. This one has been nagging me both times.
     
  5. rxcomposite
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    rxcomposite Senior Member

    Aren't you going to make a catamaran? You have to make two parts before you cut or destroy the (half) mold. That means you still have to move 1/2 (or 1/4) hull out of the way?
     
  6. CatBuilder

    CatBuilder Previous Member

    I think I'll do this, RX:

    1) Make outboard starboard half hull, move it aside.

    2) Make inboard port half hull, move it aside.

    3) Rearrange mold stations

    4) Make outboard port half hull, move it aside.

    5) Make inboard starboard half hull, leave it in the mold.

    6) Take outboard starboard half hull and put in on top of the inboard starboard half hull in the mold. Join, cut some of mold side off and remove from mold.

    7) Take outboard port half hull and put it in the mold again. Bring inboard port hull over and stick it on top. Join and remove... then throw the mold away.

    Two hulls created... no higher type of crane required other than the engine hoists (two of them).
     
  7. rberrey
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    rberrey Senior Member

    Cat I might would build a few male frames put 2x6 stringers on them add casters ( Harbor Freight) flip the hull just like you would a hull built in a male mold only backwards, role it out of your way. rick
     
  8. CatBuilder

    CatBuilder Previous Member

    I will definitely be doing something like this... moving the hulls around on dollies which might be shaped like a male mold. Definitely in the plan.

    How do I get them out of the mold though?

    That seems to be where everyone is suggesting that I can't use engine hoists. They are suggesting I build a custom travelift or get various forklifts or cranes or all kinds of things I can't get or can't afford to get.
     
  9. rberrey
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    rberrey Senior Member

    All thats too much money. You'll have to tie the two forms together ( Male to female ), sandwich the forms, use scrap ply or 2x4 ,scab ( nail ) male frame to female frame. you will have to have a few people to flip it but it will be cheeper.Build the bottem of your male frames with some rocker. Also go to the batea site and look at flips, there are alot of them. Remember as far as weight the larger bateau boats will weigh more than your 1/4 hull. Side pull is 1/10 tonnage, small chain falls and comalongs are cheep. You can build whatever type A frames you need. My hulls have chain plates designed as lift points ,you can build in lifting eyes with scrap glass and cut them out when your finished lifting your hulls. Two A frames and a 30' pipe with three pick points may be your best investment, let me think on it a few days cat. rick
     
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  10. rxcomposite
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    rxcomposite Senior Member

    Figure a man, who has eaten his breakfast (or lunch) can lift 50 lbs (1/3 of a weigth of standard man) for extended period and 80 lbs to lift overhead for a short burst. Now figure the weight of the half finished hull and divide that by 50 lbs. extended period. That will be the number of man you need for maybe 20-30 minutes.

    Now, an A frame or engine lift can easily lift 2 tons. Piece of cake. You need two to balance it, right? But you have a 45 footer partly finished hull (only one side laminated) that will be flexing like a dead fish. You need at least three lifting gear to spread the load.

    Lifting from the outside of the hull with raw foam as the lifting surface, you would not want it scoured or gouged. Use the largest flexible web strap you can find or you can line a 4" strap with cardboard and thin plywood to spread the load. You also need to protect the thin edges, line it with cardboard or wood, secured temporarily with duct tape. You also need a spreader bar to prevent pinching of the hull.

    You can use Rick's method by lifting from the inside through temporary lifting eye pads laminated over the inner hull (two for each cable wire, 4 for each lifting point) but if you have to turn over the part, it will be impossible without damaging the edges. The edges won't stand up to vertical lifting or sitting. With a limited ceiling height, you will be forced to use 30 or 40 degree lifting angle, increasing the bending force on the part. Risk of skin delaminating from the foam. Consider a spreader bar so forces will be vertical.

    I have lifted and turned over many big composite parts (largest was 20 x 50 feet deck) but it was always far from perfect. Damaged edges, scuffed surfaces. Near miss (lifting pad gave way). Each approach was different from the others. That is the reason you are getting many answers.

    You have to run it through your head. Visualize it. Sketch your plan. Where it will go, how will it turn. How you would protect the hulls.

    Remember you have to lift twice. Once to get it out of the way, second to place it back to the mating hull.
     
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  11. CatBuilder

    CatBuilder Previous Member

    Wow, thanks, RX. As usual, that is a very good answer. I'll just keep giving it thought.
     
  12. SamSam
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    SamSam Senior Member

    Moving these around will be one thing. How are they going to be held to shape once they are removed from the mold? What's the likelihood of these parts sagging etc and becoming permanently deformed while awaiting to be joined and supporting structure added? Gravity is a wonderful thing but it takes a toll on everything.
     
  13. rxcomposite
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    rxcomposite Senior Member

    I will find time and compute how much your part will flex given a span of lifting points. I am sure you posted somewere the area ang weight of the part. I need these to ditributed weight/pressure.
     
  14. rxcomposite
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    rxcomposite Senior Member

    I agree with SamSam. After a week or so, your part wont be the same as when you pulled it out of the mold. Can be frustrating to coax it back to the original shape especially that you foam is not exactly thermoformed to hold its shape.
     

  15. CatBuilder

    CatBuilder Previous Member

    Some will have permanent bulkheads already installed. Some will have temporary bulkheads just to keep the shape.
     
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