Building is starting. Several questions in here. Answer any you like! :)

Discussion in 'Fiberglass and Composite Boat Building' started by CatBuilder, Nov 12, 2010.

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  1. CatBuilder

    CatBuilder Previous Member

    I am beginning my build again. It is a Kurt Hughes 45' catamaran in foam/glass.

    Based on conversations I have had here with some very helpful people (thank you!), I am building on a male mold. The plans is to:

    a) build male mold with stations to layup entire hull
    b) run ribs/stringers along between stations to help support foam
    c) place foam on mold and hold together and in place
    d) lightly sand foam and make sure it's fair
    e) hand layup 20oz triaxial cloth on foam (3 layers)
    f) add any reinforcements required in plan (extra biaxial, etc...)
    g) roll hull over myself (using large wheels like Charly did)
    h) pull male mold from hull either in one piece or by taking apart
    i) hand layup inside glass (2 layers of 34oz triax)
    j) add any reinforcements required in plan
    k) do the second hull
    l) put non-spanning bulkheads in hulls
    l) do the bridgedeck
    m) line hulls up, then raise bridgedeck up to meet matching cut in hull
    n) tape bridgedeck in
    o) put in spanning main strength bulkheads that hold catamaran together
    p) do deck and deckhouse
    q) fit out (dagger boards and rudders should have been in these steps somewhere.

    With that type of build in mind, I have SEVERAL questions to ask. Hope you all don't mind. Please do answer any you can...

    :?:I have to fit 5 or 6lb (100kg or another weight) foam in many different areas throughout the hull. Will this be more difficult than if it were all one weight, or are the thicknesses of the foam all the same, even if the weights are different?

    :?:The inboard side of each hull has a large cutout where the bridgedeck joins both hulls together. This is not a simple cutout, but a "lip", "flange" or curvature of the main hull meeting the bridgedeck. The plans say to carry the core and laminate of the main hull up through this curve that eventually meets the bridgedeck. How do I do this? Do I make a mold with this flange already in it?

    :?:What is a taper when laying up the fiberglass and how do I do a good one?

    :?:Herman suggested using vertical laminations on the hull. I like this idea, but of course my warp orientation is fore and aft on this boat. How do I layup triaxial vertically if my warp needs to go from bow to stern? Do I cut small squares? If so, does this weaken the boat by cutting the fibers? Not understanding how to do this with 3 layers of 20oz triaxial.

    :?:Herman also mentioned doing the vertical strip, calling it a day, then starting on the next vertical strip the next morning. Can anyone help me figure out how this is done with 3 layers of 20oz triaxial? Do I lay up a few layers, then put some peel ply on the edges? If so, how do I mate one day's layup to the next to be sure of a strong structure?

    :?:The designer has plans for composite chainplates. These look great, and I'm going to do them. They involve getting into the core near the hull-deck joint and replacing some core. Do I worry about this stuff while making the hulls, or do I add that later when I'm doing rigging?

    :?:There are strips of 700gsm biaxial roving around the area where the dagger boards come through and also where the rudder cassettes go (they are kick up rudders). Do you put these strips on while you are building the hull, or do you put peel ply there and put the strips on later, when you are putting on the dagger board cases and rudder cassettes?

    I hope that is all of my questions. :D:D

    Thank you to anyone who has the patience to read through these and answer any they can. :cool:
     
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  2. TeddyDiver
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    TeddyDiver Gollywobbler

  3. TeddyDiver
    Joined: Dec 2007
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    Location: Finland/Norway

    TeddyDiver Gollywobbler

  4. Petros
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    Petros Senior Member

    I HAVE NO PERSONNEL EXPERIENCE BUILDING A BOAT THIS LARGE (i HAVE BUILT 13 SMALL BOATS), BUT I CAN GIVE YOU SOME IDEAS BASE ON MY PROFESSIONAL EXPERIENCE AS AN ENGINEER WITH 30 PLUS YEARS EXPERIENCE IN A NUMBER OF DIFFERENT INDUSTRIES:

    :?:I have to fit 5 or 6lb (100kg or another weight) foam in many different areas throughout the hull. Will this be more difficult than if it were all one weight, or are the thicknesses of the foam all the same, even if the weights are different?

    THIS WILL ADD A LOT OF WEIGHT TO THE FINISHED HULL, AND A LOT OF COST TOO. IT MIGHT EVEN EFFECT THE BALANCE. SINCE THIS IS A HAND BUILD (NOT DONE IN A PRODUCTION LINE IN A FACTORY) I SUGGEST DOING WHAT THE PLAN CALLS FOR. IF THERE ARE A FEW AREAS YOU MIGHT BE CONCERNED THE STANDARD CORE IS INADEQUATE IT WOULD DO NO HARM TO USE THE HIGHER DENSITY CORE IN THOSE AREAS, BUT I WOULD NOT JUST WHOLE SALE USE HEAVIER CORE EVERYWHERE

    :?:The inboard side of each hull has a large cutout where the bridgedeck joins both hulls together. This is not a simple cutout, but a "lip", "flange" or curvature of the main hull meeting the bridgedeck. The plans say to carry the core and laminate of the main hull up through this curve that eventually meets the bridgedeck. How do I do this? Do I make a mold with this flange already in it?

    IF I UNDERSTAND THIS CORRECTLY, I WOULD BUILD THIS FLANGE UP ON THE FOAM CORE (BEFORE YOU GLASS OVER IT), AND THAN CARRY THE CLOTH LAMINATE UP OVER THE FOAM FLANGE. YOU CAN THAN CARVE AWAY THE FOAM BUILD UP ON THE INSIDE ONCE THE MOLD IS REMOVED IF YOU NEED A CONSTANT CORE THICKNESS. KEEP IN MIND THAT THE LOAD CARRYING PART OF THE STRUCTURE IS THE SKIN, THE CORE CARRIES MUCH LOWER SHEAR AND COMPRESSION LOADS, SO THE ORIENTATION AND ATTACHMENT OF THE CORE IS MUCH LESS CRITICAL.

    :?:What is a taper when laying up the fiberglass and how do I do a good one?

    I CAN NOT HELP YOU WITH THIS ONE, BUT I KNOW THERE ARE STANDARD WAYS OF DOING THIS. PERHAPS CHECK THE WEST SYSTEMS WEBSITE.

    :?:Herman suggested using vertical laminations on the hull. I like this idea, but of course my warp orientation is fore and aft on this boat. How do I layup triaxial vertically if my warp needs to go from bow to stern? Do I cut small squares? If so, does this weaken the boat by cutting the fibers? Not understanding how to do this with 3 layers of 20oz triaxial.

    A FULL LOAD TRANSFER FROM ONE LAYER TO THE OTHER DEPENDS ON THE OVERLAP LENGTH. THAT LENGTH SHOULD ALSO BE SPECIFIED FOR YOUR PARTICULAR LAYUP, AGAIN CHECK WITH THE MANUFACTURER'S RECOMMENDATIONS. IF YOU MEET THAT OVERLAP LENGTH IT SHOULD HAVE THE SAME STRENGTH, THE PROBLEM IS OF COURSE YOU WILL HAVE MUCH MORE OVERLAPS, ADDING A LOT OF MATERIAL, COST AND WEIGHT. UNLESS YOU CAN WORK OUT AN APPROPRIATE LAP LENGTH INTO YOUR THREE LAYER LAMINATE (WHICH I AM NOT FAMILIAR), I WOULD NOT RECOMMEND THIS. THE STRENGTH OF THE LAYUP DEPENDS ON THE LOADS BEING CARRIED BY THOSE FIBERS WITHIN THE RESIN MATRIX, IF YOU DO NOT GET FULL LOAD TRANSFER AT AN OVERLAP, YOU WILL NOT HAVE A FULL STRENGTH HULL.

    :?:Herman also mentioned doing the vertical strip, calling it a day, then starting on the next vertical strip the next morning. Can anyone help me figure out how this is done with 3 layers of 20oz triaxial? Do I lay up a few layers, then put some peel ply on the edges? If so, how do I mate one day's layup to the next to be sure of a strong structure?

    IF I RECALL, THERE IS AN ALLOWED TIME LIMIT FOR BONDING THE NEXT LAYER ONTO YOUR BUILD UP THAT STILL ALLOWS FULL STRENGTH. CHECK WITH THE MATERIALS SUPPLIERS' RECOMMENDATIONS. IF IT CAN NOT BE DONE WITHIN THIS TIME WINDOW, THAN PEEL PLY IS THE ONLY WAY TO DO IT.
    :?:The designer has plans for composite chainplates. These look great, and I'm going to do them. They involve getting into the core near the hull-deck joint and replacing some core. Do I worry about this stuff while making the hulls, or do I add that later when I'm doing rigging?

    I WOULD DO THIS WHILE MAKING THE HULLS, OTHERWISE YOU HAVE TO CUT INTO THE LAYUP TO DO IT LATER. SOMETIMES THIS IS ACTUALLY PLANNED, BUT IT SEEMS IT MIGHT SAVE TIME IF YOU CAN PLAN THE LOCATION WITH ENOUGH ACCURACY TO GET IT RIGHT DURING THE HULL BUILD-UP. THE FEWER LOCATIONS WHERE THE HULL FIBERS ARE BREECHED, THE LOWER THE CHANCE OF DELAMINATIONS OR MOISTURE INTRUSION LATER.

    :?:There are strips of 700gsm biaxial roving around the area where the dagger boards come through and also where the rudder cassettes go (they are kick up rudders). Do you put these strips on while you are building the hull, or do you put peel ply there and put the strips on later, when you are putting on the dagger board cases and rudder cassettes?

    I DO NOT KNOW WHAT THE DETAIL LOOKS LIKE, BUT IT SEEMS USING PEEL PLY IS WHAT IS REQUIRED. I DO NOT SEE HOW ADDING TAPE LONG BEFORE YOU CUT HOLES THROUGH THE HULL TO BUILD UP A THROUGH HULL BOX WILL ACCOMPLISH, IS NOT THIS TAPE TO SEAL OFF THE ADDED BOX? THAN IT HAS T BE DONE WHEN THE DAGGAR BOARD AND RUDDER CASSET BOXES ARE INSTALLED.

    AREA THERE OTHER BUILDERS OF SIMILAR BOATS NEAR BY YOU CAN VISIT? tHE DESIGNER AND BOAT YARD THAT HAVE BUILT THIS DESIGN, OR SIMILAR BOATS, WOULD BE A REALLY BIG HELP TO YOU I THINK.

    GOOD LUCK
     
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  5. rxcomposite
    Joined: Jan 2005
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    rxcomposite Senior Member

    Composite Design Details

    Catbuilder,

    Red italics my answer.

    With that type of build in mind, I have SEVERAL questions to ask. Hope you all don't mind. Please do answer any you can...

    This is design details the NA usually do not draw as it is tedious and is usually relegated to the knowledge of the yard. Drawing is much easier to see but I will attempt to describe the details, giving thoughts to the way the designer approached the build. Designers can sometimes be impractical as they are not boatbuilder, which got you into trouble in the first place. Sometimes materials are hard to find in your area and you have to substitute, or sometimes the materials are hard to work with making you pull up tricks in your sleeve.

    I have to fit 5 or 6lb (100kg or another weight) foam in many different areas throughout the hull. Will this be more difficult than if it were all one weight, or are the thicknesses of the foam all the same, even if the weights are different?

    The hull has different pressures depending on the location (bottom, sides, deck, mid section, aft, an forward). The thickness of the foam (thus the weight) is chosen in accordance with the mechanical property of the foam (shear stress). During the initial design stage, the designer has many different core thickness and weights. To reduce inventory of foam sizes, he adjust it by choosing the thickness and density that will meet the design criteria. It is possible you have 3 different weights, and two thicknesses. One for the bottom, one for the sides, and one for local stiffening. Highly stressed areas requires high density foam (250 gr/m2) such as hatch opening, bridge to deck connections, anchor points such as cleats, machineries mounting, ect..

    Foam, by the limitation of its cut sizes, is also a good opportunity to incorporate shear ties in way of major structures such as bulkheads. It is not just butted but cut at 45 degree angle laminated over before the next foam is joined.

    Foam is not also terminated abruptly but tapered to 1:3 ratio to avoid shear stress concentrations. Case like transition from cored to single skin. In cases where it buts into a bulkhead and is to be terminated, a 1:3 taper is to be added to the other side.


    The inboard side of each hull has a large cutout where the bridgedeck joins both hulls together. This is not a simple cutout, but a "lip", "flange" or curvature of the main hull meeting the bridgedeck. The plans say to carry the core and laminate of the main hull up through this curve that eventually meets the bridgedeck. How do I do this? Do I make a mold with this flange already in it?

    You have to make a removable lip in the hull mold otherwise you will not be able to pull the part out of the mold. This is assuming the flange goes towards the inside of the boat. Bridge to deck connection is a highly stressed area. Do you have high density foam on this area? Is it bolted or glued to the deck?

    What is a taper when laying up the fiberglass and how do I do a good one?

    The Class standard for cloth overlap is in marine application is 2” (50mm.) minimum for an 18 ounce/yard2 (300gr/m2) or higher of fiber. This is to ensure adequate bond strength of the resin. This also goes the same for bonding structures (stiffeners, bulkheads) to the base laminate. In cases it is a multiple layer of bond, taper (after the minimum 2”) should be in the range of 1:10 of the thickness of the base laminate.

    Herman suggested using vertical laminations on the hull. I like this idea, but of course my warp orientation is fore and aft on this boat. How do I layup triaxial vertically if my warp needs to go from bow to stern? Do I cut small squares? If so, does this weaken the boat by cutting the fibers? Not understanding how to do this with 3 layers of 20oz triaxial.

    Please check if the designer has included ply orientation in the drawing. The boat has thee major stress points, forward, mid, and aft. There is a reduction of scantlings about 25% forward, and 30% aft. The mid portion receives the principal stress of compression/tension requiring extra laminate. Since the stress is mostly vertical, Herman is right. An extra mid lamination is required unless the designer just went through the calculations based on the mid part and did not bother to reduce scantlings on the fore and aft. Usually a fore and aft 0 degree orientation is added on and a -45 +45 degree is used as base. Biax or diagonal cut 0/90 WR is used in stiffeners and UNI on the crown.

    At this point, review the lamination schedule if you have one. The hull has three different thicknesses, the keel, the bottom, and the sides (and most probably different core density also). Planning the lamination sched can save you a lot of time on cutting and overlaps. For example, the keel is the thickest part and overlapping the bottom lamination over the keel (approx 1/10 of the hull width) is much better than slapping the extra layers to build up the thickness. This keel lam goes up all the way to the stem, reducing in thickness as it goes pat the waterline.

    Note also that the stem lamination goes inside the outer laminate so the outside lam goes in first. This is to prevent the stem laminate from delaminating outward in case of collision.

    At the same time, check the overlap along the edges of the transom. It is supposed to be boundary reinforced. Saves you time by cutting the fabric to cover overlap.


    Herman also mentioned doing the vertical strip, calling it a day, then starting on the next vertical strip the next morning. Can anyone help me figure out how this is done with 3 layers of 20oz triaxial? Do I lay up a few layers, then put some peel ply on the edges? If so, how do I mate one day's layup to the next to be sure of a strong structure?

    This is the “extra” lamination. I do not know how as I would be second guessing the designer. If you are using triax, peel ply the edges as it has a tendency to curl up or splay. A 2“ strip of light CSM applied on the edges will also work.

    The designer has plans for composite chainplates. These look great, and I'm going to do them. They involve getting into the core near the hull-deck joint and replacing some core. Do I worry about this stuff while making the hulls, or do I add that later when I'm doing rigging?

    Is it the same thickness as the core? The designer opted for a much denser material than high density core for added strength as it will be bolted. You will have a core to single skin transition. Follow the core taper standard.

    There are strips of 700gsm biaxial roving around the area where the dagger boards come through and also where the rudder cassettes go (they are kick up rudders). Do you put these strips on while you are building the hull, or do you put peel ply there and put the strips on later, when you are putting on the dagger board cases and rudder cassettes?

    Whenever you cut a hole in the hull, it must either be supported by a high density laminate or you transition from cored to single skin laminate with the laminate being 1.5 x the thickness of the base laminate. Even if the foam core is retained, you need to bulk it up. This is called local reinforcing. The same goes through for thru hull or anything where you will have to bore a hole in the hull so plan your core layout carefully. Saves you much time in removing inner laminate, tapering the core, laying up a new thickness. Normally, a thru hull connection drawing is made in advance.

    Rule of thumb, if it is to be bolted, solid laminate, if it support another structure, high density foam, and always 1.5x extra lamination.
     
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  6. CatBuilder

    CatBuilder Previous Member

    YIKES!!! Apparently, I'm still pretty green. :eek:

    Thank you for this response.

    There are several things in your response that I was unaware of. Can anyone suggest a good online resource that would cover building a boat like this in foam/glass? Things like tapering the core were completely unknown to me until I read this post.

    I can't afford to screw up. This is my one shot at escaping the USA's decaying economy. This is very *very* important and is not being undertaken as a hobby. It is all of my money.

    Anyone have any reading for me on composite construction basic techniques like knowing to taper the core?

    My responses are in between yours, in the standard color... yours are still red...

     
  7. Herman
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    Herman Senior Member

    Try to get hold of a "Core-Cell Design Manual" which has many schematics of how details should look like.

    The thickness of a core is not the same as the density. For reinforcing specific areas, high density foam of the same thickness can be used.
     
  8. CatBuilder

    CatBuilder Previous Member

    Thanks. I have contacted Bilodeau to ask him for his book and for the ATC Core-Cell Design Manual. The manual seems to be missing entirely as ATC is missing entirely now, absorbed by another company.

    Does anyone here have a PDF of the ATC Core-Cell Manual?

    PS: I'm very lucky with the lofting. I have full size plots for each hull station the designer included for me. :cool:
     
  9. Herman
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    Herman Senior Member

    If you do not succeed, give me a message. I have both in hardcopy.
     
  10. hoytedow
    Joined: Sep 2009
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    hoytedow wood butcher

    g) roll hull over [by](because it sounded too painful otherwise):) myself (using large wheels like Charly did)

    Make sure the large rollers have a wide foot print, especially where the strain would be the greatest, to spread the stress and thereby avoid damaging the hull during roll-over.
     
  11. CatBuilder

    CatBuilder Previous Member

    Thanks for the tip to remember about the stress points.

    I was thinking of attaching these rollers straight to the male mold and making them into the cradles that will hold the hull once rolled over.
     
  12. CatBuilder

    CatBuilder Previous Member

    That is a very nice offer, Herman. Thank you.

    I am trying to get a hold of these fairly quickly, so I can make sure to have a full understanding of technique before I begin.

    I am currently at the stage of beginning to build the mold. I can probably do at least the stations while reading the material for the hull construction techniques.

    This board is great! I couldn't ask for better friends during a build. Thank you!

    Also, Teddy... I have been looking through those links. Thank you for those.
     
  13. rxcomposite
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    rxcomposite Senior Member

    More Design Details

    Catbuilder,

    Before we proceed further, let me call your attention to the things you have missed or failed to ask.

    Haunch- That large radius in the inboard shell of the hull connected to the crossbeam. This is a critical area and needs to be reinforced. It usually receives the same lamination schedule as the bottom. If the radius is small, the extra layer covers the radii plus some 2” on each side.

    Crossflow bulkheads- This is a class requirement. The bulkhead that prevent water from entering the opposite side of the hull when one section is breached. You may place it right after the haunch, one on each side or just one in the middle of the crossbeam.

    Limber holes- Limber holes are drain holes integrated into the frames and stiffeners so that water does not collect in the stiffener grillage. The hole height shall not exceed ¼ of the depth of the stiffener/frame and shall be located at ¼ of the span where there is least vertical stress. Plan the drainage carefully as it will be almost impossible to drill these holes in the beam after it is glassed over without sacrificing the integrity of the hull laminate. Also by planning, you need only limber holes as necessary.

    Bulkheads holes, Bulkheads are meant to be watertight but holes are necessary evils. You need holes for the plumbing, electricals, mechanicals, to pass through. The bulkheads must be watertight so you must have to seal it afterwards. Your bulkhead is cored so that complicates the problem. High density cores, solid laminate, reinforcing of the holes, possible bolting. You know how hard it is to work on areas of a very tight catamaran hull when everything has been fixed.

    Rx
     
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  14. AndrewK
    Joined: Mar 2007
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    AndrewK Senior Member

    CatBuilder; I see you have received lots of good advice already, I will add only where I think your questions have not been fully answered.
    But I will also say that you should rethink the conventional strip planking versus transverse as transverse is far easier for one person. I can send you some pictures if you like.



    :?:I have to fit 5 or 6lb (100kg or another weight) foam in many different areas throughout the hull. Will this be more difficult than if it were all one weight, or are the thicknesses of the foam all the same, even if the weights are different?

    Thickness will be the same. High density foam is super expensive alternative under bolted down deck gear is to make up a harry bog, to your resin mix add milled glass and silica.

    :?:The inboard side of each hull has a large cutout where the bridgedeck joins both hulls together. This is not a simple cutout, but a "lip", "flange" or curvature of the main hull meeting the bridgedeck. The plans say to carry the core and laminate of the main hull up through this curve that eventually meets the bridgedeck. How do I do this? Do I make a mold with this flange already in it?

    If it is a curved chamfer then yes, if flat then I think it is easier to produce this on a table and add later.

    :?:Herman suggested using vertical laminations on the hull. I like this idea, but of course my warp orientation is fore and aft on this boat. How do I layup triaxial vertically if my warp needs to go from bow to stern? Do I cut small squares? If so, does this weaken the boat by cutting the fibers? Not understanding how to do this with 3 layers of 20oz triaxial.

    Are you certain that all 3 layers are orientated fore and aft?
    if yes then what you need is weft triaxial so that when you lay the cloth transversally the fiber will be fore and aft.


    :?:Herman also mentioned doing the vertical strip, calling it a day, then starting on the next vertical strip the next morning. Can anyone help me figure out how this is done with 3 layers of 20oz triaxial? Do I lay up a few layers, then put some peel ply on the edges? If so, how do I mate one day's layup to the next to be sure of a strong structure?

    If the above orientation is correct then you lay 3 strips of first layer, next layer you offset by 1/3 and final layer by another third.
    I know its not necessary but personally I recommend peel plying the entire laminate not just the edge at the end of the day.
    Also regarding your cloth edge overlaps, a lot of triaxials have a salvege edge, usually 20 - 30 mm of +/-45 fiber alone which makes the overlaps simple.

    :?:The designer has plans for composite chainplates. These look great, and I'm going to do them. They involve getting into the core near the hull-deck joint and replacing some core. Do I worry about this stuff while making the hulls, or do I add that later when I'm doing rigging?

    There are a number of ways doing the composite chain plates, if they are located on the hull sides then I would prefabricate these first. I can send you photos of what I did.

    :?:There are strips of 700gsm biaxial roving around the area where the dagger boards come through and also where the rudder cassettes go (they are kick up rudders). Do you put these strips on while you are building the hull, or do you put peel ply there and put the strips on later, when you are putting on the dagger board cases and rudder cassettes?
    Always best to minimise secondary bonding so incorporate extra reinforcement into the initial hull laminate as much as possible.
     
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  15. rxcomposite
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    rxcomposite Senior Member

    Part 2 of design details

    Red italics mine.

    Ok, thanks. Very good general advice. So the design is something to build to, but doesn't always give you the exact technique, correct?

    Yes. The skill of the laminator or the foreman will bridge the gap.


    Thanks. I do understand about correctly joining bulkheads because I saw this somewhere online. There was a foam piece as a "buffer' between the bulkhead and the hull. I also understand the foam in different densities (5# or 6#), but isn't it the same thickness? I had thought a 5# foam was just a lighter or "fluffier" foam than a 6# density. Is this not the case? I can't see how you would build a hull fair if the foam is all different thicknesses. The layup on top of the foam would come out terribly, correct?

    Yes. In your case, this is a “one off” foam core. The lay up will bulge on the overlaps. You can cut a wide groove on the core as illustrated in the drawing but this will only help you in the first layer. The second and third layer will bulge and there is not anything you can do about it except to fair the hull. No problem on the inner layer though as you don’t have to fair it.

    No, actually the flange goes outward, toward the flat bridgedeck like this one, but much less dramatic... less of a lip. Much smaller.

    So I make this on the mold like this other guy did?

    That is OK as long as it will mate. That inner curve portion is the haunch.

    Ok, I almost understand this part. I have 3 layers of 20oz/yd (678 gsm) triaxial. This is used to laminate the hull. If I taper this, how do I do it? Do I have to cut some layers of the triaxial to make it taper? How do I get the 1:10 taper? I just don't understand the technique used. Is there some online resource I can look at. I know this is a very basic question.

    You don’t taper the triax, you stagger the overlap as shown in the drawing. 2” first, the 1” for every layer. Your inner laminate is 0.10”, so 0.10 x 10 = 1.0” as shown in the drawing.


    Yes, this I do understand. I am planning to put, for example, the keel lamination in as I lay up the hull. On the outside, my keel is foam, then 3 layers of triaxial, then extra laminates for collisions forward. I would put this on as I do the hull, correct?

    I have include this in the drawing. You will have to cut a wide groove on the foam if you don’t want the keel reinforcing bulging out. BTW, the keel width is constant, it just folds when it reaches the stem.

    Excellent tip on the stem. It makes sense that it has to go inside the outer layer so it will be properly encapsulated. I'll check on the transom.

    Same technique applies. Cut a wide groove 2” on the hull, 2” on the transom, reinforce with 4” wide strip then layup the second layer.
    I
    nside it's foam, then 10" wide biaxial tape, then foam strip with structural filler, then 2(qty) 10" biaxial tapes lapped over each other. I planned to add this after I do the biaxial layup inside the hull. Is that correct?

    Yes, although the proper way is that both sides should be reinforced but I guess that is OK.

    I'm not second guessing the designer at all. He's good. Very good. I am just looking to find out the best way to laminate the hull (3 layers of 700 gsm triax with warp running fore and aft). I am one guy. Herman suggested I could laminate from bilge to sheer so I could start and stop laminating at any time. The designer does not have "instructions" on how to build a boat. He has a few great tips in his cylinder mold package, which I learned a lot from, but now that I am doing foam/glass, I have a set of plans geared a bit more for the professional - which I am not. I am trying to understand the "how to" of doing these laminations as one person.


    I guess “second guessing” is not the proper word I should use. That would mean the first one is a guess and it is the designer.
    You can laminate from keel to sheer then do the overlap at the same time for the keel lam. You can stop anytime you complete the laminate an do the next layer within 4 hours. Man, you gotta sleep too, so whenever it is more than 8 hours interval, do a light sanding on the cured laminate before you start with the second layer. In theory, lamination is supposed to be a continous process averaging about an hour before you start on the second layer. By the time you are at the end of the boat, the front end has “tacky cured”. Figure about 6 to 7 lbs/hour material deposition rate. That includes fiber placement.


    It is the same thickness as the core. There are "glass beads" in there where the core would be. There is nothing bolted. These are composite chainplates I'm talking about available in the design. They are many *many* layers of glass in varying directions around a modified core of glass beads. These layers of fiberglass hold a pin that then holds the rigging. So do I add this stuff later on? I don't think there is a way to do it while I'm laminating the hulls, right?

    Yes I think it is a good idea to carve out the foam later. But do this before you laminate the inner layer. The designer gave many fabric orientations to achieve an isothrophic quality of the laminate. Biax or WR is good only on two directions.
     

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