# I've Made a Model



## WhiteDog70810 (May 6, 2008)

At Brett's suggestion, I've made a model of my creation.  For those that are interested in the back story, this was my original idea.










It was okay, but I refined it a bit and made it 18 ft.










While I feel that design is probably a better all around boat, it would require a lot more money to build and set up, so I returned to my 16 ft plan and removed the stringers and raised sole.  For low power, they aren't necessary.  This is what I got.




























I have now created a 1:4 scale model using 1/8" masonite.  




























I like the modeling approach, but I really was glad I had the digital model to pull measurements from. I had hoped to create a table of offsets from the model, but despite my best efforts, I can't rely on the accuracy of my measurements when I scale the dimensions back up.  I have come to the conclusion that I will build a jig and "wrap" the sides on to the full size frames in order to get the points to scribe the curves for the sides.  I had hoped to cut everything flat and stitch the sides, sole and transom together and add the frames afterward.  Oh well.  Now I just have to get the ply.  

Thank goodness the most accurate tool I had could only get to the closest 1/32".  If I had the capability to measure to 1/64", I would be really pissed because of my inability to be accurate because my pencil marks were too thick.  I can be kinda OCD.

Nate


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## jasonrl23 (Jul 27, 2009)

Nice! 

Your first model reminds me of what a streamlined gheenoe might look like. It looks good. Defintely like the updated versions much better though.


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## Brett (Jul 16, 2008)

I see a bit of swamp boat lines in that model.
Looks kinda like an Atchafalaya crawfish pirogue.
Stitch and tape construction won't give you the most accurate work,
still, when you get to full scale construction you'll find yourself adjusting
frames and bulkheads to make the lines look better as you work.
Don't sweat the sixteenths, that's what block planes and sandpaper are for.
Wood boats are supposed to have life in their lines, not be pixel perfect.
Looking forward to seeing the final build, good work.


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## firecat1981 (Nov 27, 2007)

nate with a bottom as flat as that you realy don't need to build a jig. 2 of my original models were flat bottoms but I went with a small v up front for a smoother ride. I learned while making the model that the flat bottom would have simplified the process and would have cut my build time by 1/3rd. Bateau.com had a few good write-ups about the style you want to make. good luck.


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## JaredFacemyer (Jul 29, 2009)

Those are some awesome models, what program did you use?


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## WhiteDog70810 (May 6, 2008)

I used Google Sketchup to draw the digital model.  It is not nearly as complex as some of the CAD programs, but it also doesn't have the bells and whistles.  I played with the free Delfship but couldn't figure out how to get it to work well.  It was hard for me to draw good curves.  However, Delfship will break the model down and show you the dimensions of the parts in as you would cut them out of the ply.  Sketchup will not do that.  

I really like having the digital model for reference.  However, it was much easier to build the 1:4 model than it was to learn how to draw it on the computer. Fortunately, I had plenty of time while deployed to figure it out. 

The masonite is easy to work with and I got some useful info from the 1:4 scale model.  I tried a 1:12 model out of cardboard, but I had trouble being accurate, but for figuring out basic shape, it would be a quicker approach.  There is no need to spend the time making a 1:4 model until you have the big picture firmly in your head. 

Regarding accuracy, I figure the more obsessive I am in my planning, the more minor my deviations will be when it comes time to build.  Trust me, I don't expect perfection nor do I really care about 1/16" screwups.  However, 1/2" screw ups will keep me awake at night.
;D
Nate


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## firecat1981 (Nov 27, 2007)

trust me, at first the 1/2 inche screw ups bothered me but a little putty and shes all pretty again ;D

The biggest problem I've run into is that the masonite, the same stuff I used for modeling, doesn't act at all like wood. When I designed and even modeled my boat it was planned that the 2 bulkheads and transom would be of equal size and shape so the only variation would be the bow. Well that didn't work out at all, when I stitched it all together is had a very wavey and unnatural shape and looked really bad, so I had to remove it all and rebuild everything to the natural shape and curve of the wood. I'm really glad I did it cause it looks sweet now and gave me alot more room to build decks, plus the new shape should be a dryer ride.
I guess my point is unless your constructing a mold to lay FB in, which your not obviously, Don't count to much on finalized plans cause things will always change.


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## WhiteDog70810 (May 6, 2008)

Good point. I am trying to make it so all the curves are as gentle as possible and only make the wood to flex in one direction. The model has a slight twist in the sides toward the front half of the boat that will not be kosher with real ply. I expect there will be significant artistic license taken before it is said and done.

Nate


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## firecat1981 (Nov 27, 2007)

well don't worry to much about it, the luan can bend in many ways and is easy to work with. did you look at that web site? if you use their process but just use temp bulkheads instead of making seats you can have this boat done in just a few weeks.
I just flipped my hull a few hours ago and I can tell you that the stitch and glue meathod did produce a nice tight seam.


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## B.Lee (Apr 29, 2008)

A 1/2" screw up is relative. It really depends where that screw up is located!

There is not much that a sanding block, some thickened epoxy, and some glass cloth can't correct. 

I like the looks of your model, and I like that you simplified the design. I thought your original design was a bit over-built. 

Are you using luan, marine ply, or what?

I flipped the Sawdust Skiff this weekend, and pretty soon will be done with Brett's construction base. I have been directed to pass it on to build another one, are you nearby? :-?


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## WhiteDog70810 (May 6, 2008)

I've cruised the Bateau site for years and have dug through their tutorials extensively. If they made a 16 ft D15 or a flat bottom FS18, I wouldn't be doing this myself. I am going to print out a few of the tutorials and may order the SC16 plans (very similar dimensions and bill of materials) before I get in to the thick of it so that I have some references. 

I plan on using Marine Ply and wrapping it around temp bulkheads. Thanks for the offer of the base. It would save me some time. However, I am up in NC, so I will have to figure it out on my own. 

Nate


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## B.Lee (Apr 29, 2008)

Same reason I designed my own skiff. After mulling over various bateau designs, I wanted soemthing that was my own. FS18 was too long, too narrow. SC16 was close, but too unstable. FS14 & 17 are cool, but too much draft. I took some of each, threw in some of Brett's ideas, and managed to mold it all into the picture I had in my head. 

Once you have a model in your hands, it really fuels the build process forward. I'll be watching in the peanut gallery...


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## firecat1981 (Nov 27, 2007)

Contruction base? we don't need no stinkin construction base ;D  ...........Although it would help.

I wouldn't bother ordering the plans cause all you will really get is sized cut outs that won't suit your build. just go at it, after a few days of work you will see the big picture. the design you made is nice and simple and you won't have any issues bending the ply to form it. I'd sooner work off your cad design, but I'd follow the bateau meathod.
(ie stitch the bow, stitch the sides to the transom, install bulkheads to get form then scribe the bottom from there.....this is extremely simple and would have saved me 10 days if I did a flat bottom)


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## WhiteDog70810 (May 6, 2008)

With the SC16, the bill of materials is 4 sheets 1/4" ply and 2 sheets 1/2" ply. With that little 1/2" ply, I think they use 1/4" for the upper decks. If so, I want to see how they are bracing the decks that aren't supported by flotation foam. No one has a good build gallery on Bateau that shows using 1/4" ply for the decks. Since the dimensions and spans of my hull are very similar, I'd like to use 1/4" to save weight if possible.

Nate


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## Brett (Jul 16, 2008)

During the framing of the bow deck on the Slipper,
I learned that adding a bend to the plywood adds rigidity.
After completing the build, I realized I could have used 1/4 luan
by simply adding a skin of 6 ounce glass to the underside of the deck
as well as the skin on top. Between the two layers of glass
and the curvature of the plywood, the flex inherent in the luan
is almost eliminated. And as a side benefit, the decks become self draining.

http://picasaweb.google.com/bdefalco/BuildingTheGrassSlipper#5225180380678094962

http://picasaweb.google.com/bdefalco/BuildingTheGrassSlipper#5226652703471055874

http://picasaweb.google.com/bdefalco/BuildingTheGrassSlipper#5230733367492553778


As to framing spacing, 16 inches on center port to starboard.

http://picasaweb.google.com/bdefalco/BuildingTheGrassSlipper#5227821824864453970


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## firecat1981 (Nov 27, 2007)

Nate if you look through the pictures on the sc16 you can see they used the 1/2" for the decks in a few of them. as far as bracing goes you would need very little because of how narrow the design is. Just some blocks on the sides and a bulkhead or 2 and it will be sturdy especially once its glassed. 
As far as floatation foam goes, I thought the same as you, that it can be used as a structural brace but I was told otherwise by several people in the know. Basically there are several different activators for expanding foam and the floatation one will get you nice lite foam, but it will be structurally weak and easily compressed if used under a deck as bracing. If you use a denser activator then you can do that, but it won't give you the floatation you will be looking for.

your best bet right now is to go to customegheenoe.com and look at how the DIY guys made there own decks and floors. Just like here theres alot of great guys and good info. also since your great with CAD renderings and all heres a link to some old designs that a few have artist renderings and blueprints.
http://www.svensons.com/boat/

enjoy.


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## WhiteDog70810 (May 6, 2008)

Great with CAD? Now you're just buttering my up.


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## firecat1981 (Nov 27, 2007)

Well you figured out how to make a computer model where i had to go old school. Although the concept of a computer model really didn't occur to me till I saw yours. but it would have been a good tool to use especially since I had a bunch of people ask me where they could buy the plans for my boat


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## Frank_Sebastian (Oct 15, 2007)

Nate if you are ever around Sebastian I would like to take you for a ride in my D15. I have built a lot of boats during my lifetime. The D15 has something about it that I can't get enough of. It seems a perfect balance between all things that I like in a boat. When fishing general species like trout, sheephead, flounder and the like I run an 8 HP 2 stroke Tohatsu. When fishing bait and spots I change over to a 3.5 four stroke Tohatsu. I have 5 registered boats between 22' and 14'. The D15 gets the call 90% of the time anymore. I also have a GV 18 cut out and ready to assemble. (shrimper)

Best regards,
FRank_S


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## firecat1981 (Nov 27, 2007)

Frank the d15 was what I was gonna build before I decided to design my own. do you have pictures of the build process? and is it a flat hull?


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## Brett (Jul 16, 2008)

link to D15 build

http://www.pbase.com/alball/d15_indian_river_skiff_construction


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## firecat1981 (Nov 27, 2007)

looks great. However I am glad I went with my design because I think it fits me better.


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## Frank_Sebastian (Oct 15, 2007)

One plus I didn't mention is that it was built in one weekend. Sort of instant gratification. I have changed a lot of things from the original. Some on the original build and some later.

Frank_S


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## WhiteDog70810 (May 6, 2008)

Frank,

Thanks for the offer. I would love to ride in a D15 because I think it is a beautiful little boat. If I am ever in the area, I'll let you know. 

I can see how you would use a simple boat more than any other. When I was a kid, my dad had a beater 14 ft Starcraft V-hull with a 15 horse white Merc. We fished four people out of that thing for years. It leaked because a tree fell on it and popped some rivets, so the bottom made an awesome live well. It would barely plane with a full load. The funny thing was that we fished less after we got a bigger and better boat. Explain that. My dad eventually got an even bigger and better boat. Now he barely fishes at all. There is a moral to this story. Keep It Simple Stupid! I think on some subconscious level, all the high speed perks take some of the fun out of it.

Nate


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## WhiteDog70810 (May 6, 2008)

All,

What is the necessary vertical dimension of under deck bracing? I picked up the idea that they had to be 3" wide somewhere, but I can't verify that. They'll be spanning approximately 24-38" depending on location. I am planning on using 1/4" ply and cambering the deck across the width of the hull to increase the longitudinal rigidity. 

I need to fit a 3.5 gal tank under my front deck and my current opening is 11 3/16" high. Even if it fits, it will be snug. By narrowing the deck braces, I can get some wiggle room, but I don't want a "flexible deck". Does anyone have a vertical measurement of a standard plastic 3.5 gal outboard tank? I don't have one.

Next question. How sticky is flotation foam? I was thinking of filling the gaps under the decks between braces with it. It will be completely nonstructural and fairly well protected, but it must adhere well enough not to vibrate off. Will a coating of epoxy toughen up the surface a little to prevent it from shredding from minor bumps and dings?

Nate


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## Brett (Jul 16, 2008)

3.1 gal merc-hat-san
14-1/2 inches long
10-1/2 inches wide
9-1/2 inches tall
after it ages and expands a little...


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## WhiteDog70810 (May 6, 2008)

Thanks Brett. That means I am just creating headaches for myself.

Nate


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## Brett (Jul 16, 2008)

I had to think back on some old hulls I've repaired.
And I remember under gunnel foam that was polyurethane.
It had been applied by inverting the hull, then pouring in place.
No visible fasteners, just foam. It appeared that the rough
texture of the raw fiberglass and the pour-in-place foam
were more than enough to keep the foam in position for years.
You could get the same effect by epoxying a strip of lumber to the hull
and bulkheads that the foam would expand around and lock it in place.


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## WhiteDog70810 (May 6, 2008)

Brett,

If I use 2 part flotation foam, I figured I'd have to invert the hull.  I like the retention strips.  

I was also thinking I could potentially cut foam insulation panels to fit with a utility knife and Gorilla glue them under the deck.  It would have less buoyancy, but it would be dang easy to work with.  However I think that stuff soaks up water over time, so I'd have to find way to seal it.  Bateau mentioned using it for under deck stiffeners on light boats so long as it is fully fiberglassed and protected from abuse.  I think the foam panel is just an excuse to use more fiberglass, but if epoxy sticks to it, I could fillet it in and cover it with 6 oz biax.  

I am trying to find ways to stuff more flotation into the boat without making the flotation chambers bigger.

 Flotation foam :-/ Foam panel

... 2 part foam is simpler.

Nate


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## Brett (Jul 16, 2008)

Polystyrene packing peanuts and nylon mesh laundry bags.
Here's the part where I get the chance to tell you to...

                                    "Stuff it!"

                                          

Fill the bags with packing peanuts, tie them off, 
and stuff the bag full of foam peanuts wherever they'll fit.


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## DSampiero (Oct 18, 2009)

Brett, you forgot to mention how important it is to get polystyrene peanuts. I am sure you all know many packing peanuts are now made of water soluble starch. Which aside from having the tendency to dissolve also weigh more than polystyrene.


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## WhiteDog70810 (May 6, 2008)

That solves an issue I've been pondering.  I don't trust sealed flotation compartments.  I just don't like not being able to peek in there and make sure it was dry, plus it can make wiring nav lights and filleting the underside of the deck rather impossible.  I was thinking of using mesh bags of ping pong balls to fill the space and installing inspection ports so I can get in there if necessary.  I was trying to think of a good source of ping pong balls in bulk.  Packing peanuts would be cheaper and easier to get and I can replace them as they crumble.  I wouldn't use the cornstarch ones naturally.  Another good idea.  Thanks.

Nate


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## Brett (Jul 16, 2008)

First time I've ever told someone to "stuff it" and was thanked.

;D

The mesh bag drawstring makes for a convenient way to tie it in place.
Not my idea though, I read it in a kayak building book years ago.


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## WhiteDog70810 (May 6, 2008)

I have another question along the lines of flotation foam. Is there a flotation foam that comes in sheets that epoxy will adhere to? All Bateau has is 2 part pourable foam. I could use insulation foam panels, but I'd rather use something that is meant to be a flotation foam. I've found PE foam sheets, but I don't think the epoxy will adhere to it. It is more for seats and cushions I think. 

Nate


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## firecat1981 (Nov 27, 2007)

I used the white foam boards they sell at home depot. It's the same foam they use to make boogy boards, floatation toss rings, and coolers. If your using epoxy resin then you will have no problems.


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## Brett (Jul 16, 2008)

Several types of foam available for use.
Polystyrene - the foam used to make cheap disposable coolers and packing peanuts
Polyurethane - the 2 part pourable foam, can be bought in panels and blocks
Polyisocyanurate - much like polyurethane, but stronger
All can be bonded with epoxy, but polystyrene will dissolve
if it comes in contact with petroleum products, polyester or vinylester resins

Preformed blocks, panels, flexible skins...

http://www.generalplastics.com/products/index.php?PHPSESSID=2ab2a955d6c9c9a00b00b862c1450571


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## WhiteDog70810 (May 6, 2008)

Yes, I am going to use epoxy. I'll probably just get the polyisocyranurate from Lowes. I think something a little more resistant to bumps and fuel would be appropriate. 

Thanks,

Nate


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