Small, stable, modular boat for photography

Discussion in 'Boat Design' started by CallMeGeorge, May 28, 2022.

  1. CallMeGeorge
    Joined: May 2022
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    Location: Ohio

    CallMeGeorge Junior Member

    I read that article early on. I have not found a current model with metal rod for tie down. No prone position available. I may end up having to use a contraption to lift the boat to the roof, but would rather not. Expandacraft, if it checks out, is an existing wheel that does everything I want. Good info re the strength of bond between wood and epoxy--though the paper I downloaded seems to disagree. I'll keep reading.
     
  2. CallMeGeorge
    Joined: May 2022
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    Location: Ohio

    CallMeGeorge Junior Member

    I mostly want prone position while the boat is stationary and watching ducks, etc. I expect to fabricate some sort of support for my chest. I may also extend the tiller control with cables. I'll adapt. The main thing is to have the flexibility to do what works best depending on conditions.
     
  3. Rumars
    Joined: Mar 2013
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    Rumars Senior Member

    1. Lying prone will not bring the camera closer to the water, you are still at least a foot over it. If you want it closer, use a crane with a remote screen, then you can sit however you want. This works regardless of boat type.
    If you are shooting film there are other solutions, wich involve you getting wet. For that a simple big board (surf or stand up) is enough, but you have to invest in camera protection gear (think scuba).

    2. Mounting hardware like metal D-rings, bars, etc. is done by bolting with plate backers and sealant. HDPE can also be welded and fiberglass or wood glued, if you prefer non-metal strongpoints. No boat will come from the factory equipped exactly for your needs, that's your job and it's limited only by your imagination.

    3. If you break a wood epoxy bond in the glue and not the wood, you did something wrong, either prep or materials. Read the gougeon book on boatbuilding, it's free online. Countless boats have been built according to it and are still floating. BTW, wood does not rot under fiberglass if done correctly, million dollar yachts are built that way.
    The Gougeon Brothers On Boat Construction book https://www.westsystem.com/the-gougeon-brothers-on-boat-construction/
    Anyway, if you don't trust glue there are always screws and rivets, boats have been built before glue.
     
  4. CallMeGeorge
    Joined: May 2022
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    Location: Ohio

    CallMeGeorge Junior Member

    All of the issues raised in the paper I linked above are related to excessive moisture in the wood. So you are correct, when the wood is sealed with epoxy on all surfaces and the structure is sufficiently stiff rot will not be an issue. I spent 45 minutes or so in the Gougeon brothers book, too. They are good engineers and competent craftsman. I do now have confidence in the process when done right. (I watched a video in which both sides of a bulkhead were sealed, but the thin perimeter face was not. The unsealed edge spanned an open drainage channel on the floor of the hull, setting up for water to wash against the raw edge of the bulkhead. Apparently not everyone is as careful as the Gougeon brothers. Not that this invalidates the process; I just found it interesting.)
     
  5. ExileMoon
    Joined: Oct 2009
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    Location: Shanghai

    ExileMoon Junior Member

    I made a design hope it will help you. This raft is made of a solid foamed PE bottom plate and a 5mm plywood board that is laminated up and down. The structure is very simple. 8 feet long and 4 feet wide (limited by the size of a single sheet of plywood).

    Her draft is 4 inches to accommodate very shallow water (displacement 230KG/507 lbs). The freeboard height is 8 inches, which might be lower if only from a photography perspective, but considering the hull of the raft is tilted when people are moving on the raft, I think 8 inches would be better.

    The volume of the foamed PE hull is about 800L, if the foam density is 50KG/M3, the weight is about 40KG/88 lbs. The plywood deck weighs about 10KG/22 lbs.
    The total is about 50KG/110 lbs.

    The edge of the plywood deck is not necessary, I think, deducting 10 inches of the edge is acceptable. This can save a little weight (2KG) appropriately. If EPS foam is used, 10KG/M3 insulation material can be found in the market (this material is relatively fragile), and the weight of the foam hull can be greatly reduced (32KG).
    Then in the limit state, the total weight is 16KG/32 pounds.

    It can be seen that the density of the foam is a decisive factor in the overall weight of the boat. Perhaps the choice of 30KG/M3 material (EPE or XPS)is a moderate consideration.
     

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  6. Skyak
    Joined: Jul 2012
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    Skyak Senior Member

    I first saw them over a year ago. It appears to be a marketing guy creating his dream company. The appeal of "Lego style" solutions is obvious. I can't tell you how many times I have seen them proposed or "invented". Marketing guys secret to success is don't sell things you have to explain.
    It looks like he hired a competent designer. The wave piercing ends are as good as it gets.
    I am confident that Expandacraft is legit, with any direct-to-consumer company you need to watch for internet clone scams, only buy with a credit card (preferably single use number), and watch them like a hawk.
    If you do go with expandacraft I hope you will close this thread out with your objective experience -it is a common question.
     
  7. Squidly-Diddly
    Joined: Sep 2007
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    Squidly-Diddly Senior Member

    saw similar to this with a piece of trapezoid plywood strapped to three forward handholds to create an elevated hard platform. IIRC the platform also had about 2" rim. Sea Eagle SE9 4 person Inflatable Boat. Package Prices starting at $549 plus FREE Shipping https://www.seaeagle.com/MotormountBoats/SE9#packages-2
    Note they CLAIM 15min inflation time and one review says 1.5 HOUR setup if using trolling motor (I HOPE that includes a few long walks from car to dock lugging motor and batt, etc.) I'd also invest in good brand name 18v dual use vac/blower with attachment to inflate and DEFLATE (forcefully sucking air out really helps get air out to pack up if you don't have nice carpeted living room to roll out extra air).
    But that brings up a very important side issue: What is your tolerance for setup and take down and getting to the water? And mud and mess when packing up? You might want to invest in car top cargo carrier Rocket Box just to keep muddy swamp water deflated boat out of the car. When just kayaking in nice clean lakes and streams no matter how much I rinse off with self showers of gallons of tap water, the entire car soon smells like low tide.

    In my small boating I've always found once you get out on the water everything is great but launching and loading are always real work.
    Click my handle for my post about turning an Ice Sled into combo roof top cargo carrier AND mini-boat with possible small motor option.
     
  8. CallMeGeorge
    Joined: May 2022
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    CallMeGeorge Junior Member

    I decided to buy an Expandacraft 12 foot catamaran. Submitted the "request for quote" form online, with two deck plates for a wider stance. Expected to receive a quote including shipping costs, for a firm fixed total price. Instead I got a request for a deposit, with no quote at all. I agreed to place a deposit after receipt of quote for total cost including shipping. After two iterations of that exchange, I was invoiced via PayPal for $200, still without ever seeing the total cost. Given the questionable behavior of invoicing for a deposit without setting a firm price, combined with the difficulty of finding anyone who has ever actually used the product (only found users via comments on the Expandacraft Facebook page), I cancelled the invoice and broke off discussion.
     
  9. CallMeGeorge
    Joined: May 2022
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    CallMeGeorge Junior Member

    I'll look into the lighter version of this design, as it can be loaded on a rooftop carrier by me alone. Thanks.
     
  10. CallMeGeorge
    Joined: May 2022
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    CallMeGeorge Junior Member

    I'm leery of punctures.
     
  11. Skyak
    Joined: Jul 2012
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    Skyak Senior Member

    Sorry to hear you got the runaround and it didn't work out. Other than shipping I don't see why you can't just click to buy. I don't think it's anything nefarious, just incompetence. If they were crooks they would take your money as fast as they could, no questions. You likely avoided a lot of frustration.
    FWIW I ordered a drop stitch inflatable SUP/SOT board Monday the 27th and it was on my stoop by 10am this morning. Walmart had a deal for $150 -now $212.
    I am against depending on air pressure for structure, but the local kayak rental company has been running them down the river for 4 seasons now and I see no patches on them.
    Kids prefer them and I would not want a solid SUP with storage and transport issues, so I'll try one, use it when I travel, leave it at the lake house for kids.
    Bestway Hydro-Force Sunspotter SUP 11 Ft. 2 In. Inflatable 2 in 1 Stand Up Paddle Board and Kayak - Walmart.com
    Thanks for sharing your experience.
     
  12. Skyak
    Joined: Jul 2012
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    Skyak Senior Member

    George, after opening and inspecting my new inflatable SUP I am far less concerned about punctures. The construction is 3 layers of PVC impregnated fabric (I presume polyester). Compared to the 1100 denier common in folding kayaks it looks like similar fabric with twice the PVC fill for 2 layers with a PVC layer between and the PVC is much harder. Plasticizers are added to PVC to make it flexible by impairing some bonds -the SUP has minimal amounts.
    If you are not using this far from land (life and death) I would not worry about puncture. If you see it you would worry more about folding in cold weather.
    Anyway, it looks like a reasonable solution to the challenging part of your problem.
     
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  13. CallMeGeorge
    Joined: May 2022
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    Location: Ohio

    CallMeGeorge Junior Member

    This SUP does seem to be of higher quality than usual for an inflatable. Not sure if a motor can be mounted, or the tripod. But for the price it might be worth doing now, leaving the full solution for another time.
     
  14. Skyak
    Joined: Jul 2012
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    Skyak Senior Member

    Exactly. This is what I see as a "minimum viable product" that gets you on the water this season. You might not go far but you can learn a lot about how you want to operate and might find that just going down stream offers plenty. I find rivers offer more than twice the animal photo-ops and free one way silent propulsion.
    A motor can certainly be mounted but there is work and a bit of commitment.
    My first thought was a thruster or two mounted on the skegs. Apparently that is the first thought of dozens of people -lots of attempts and everything cheap is from China.
    -thrusters have protection and control but will be inefficient particularly at speed.
    The other way to go is a motor above the surface through a leg. This design has the freedom to mount a fat high torque motor and a large efficient free prop and would be easy to share among other small boats (8 in my fleet not counting inflatables). This makes more sense for my fleet and your ambivalence toward the board.

    Mounting a tripod is simple enough, but the craft rotates about its COB (center of buoyancy) so the distance between the COB and the camera times the zoom would be the stability quality factor. My solution AYR was to separate the viewer from the camera on a stabilizer boom. Try it your way, and maybe try just leaning back with the camera closer to the COB.

    For my money I will look for a camera I can adapt to my old high quality lenses and remote viewers (phones and tablets). Not sure that electric setup will happen this year. Maybe the family will be more interested and get me going.
    Last night a bunch of Wax wings were putting on a show by the confluence. If my phone only had telephoto...
     
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  15. CallMeGeorge
    Joined: May 2022
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    CallMeGeorge Junior Member

    The purpose of the motor is to get me upstream so I can drift back to the car.

    I'm not following mounting a motor "through a leg." I don't see a through hole in the photos.

    I'm not seeing how to mount the tripod (or stabilizer boom) without piercing the bladder.

    Thanks for the info re the center of rotation being at the center of buoyancy. I did not know that, and likely would never have thought of it.

    I will be using a camera and lens combo that weighs 7 lbs. It's hard to imagine a boom that will be stiff enough without weighing a ton (hyperbolically speaking). I was planning to use a ground tripod to minimize the rotational moment of inertia.

    Cedar waxwings are the epitome of elegance.
     
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