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Home made float

Thread Status: Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.
Fox,

I originally started with the idea of something like the attached pic. I quickly realized that an inflatable will obviously prove to be a bad idea for anything with a dorsal fin. I contacted some people with a tremendous amount of knowledge in boat design and they have been helping me through the process. I can make a float no problem, but a large scale project such as this, I would definitely need some help with.

Anyways, according to the product info for the pic- One of the oldest watercrafts known to man is a flat boat, which is neither a canoe nor kayak. Used by Polynesians to travel a thousand years ago from island to island and face storms and high seas. These modern Sit On Tops are ideally suited as rental craft because a novice can paddle it and it can easily be reboarded.

This alone made it clear to me that I could easily ditch the kayak and alternate between it and a flat boat.

After several different design blueprints, I decided that buoyancy billets would be my core material since their standard application is to float things in water and are inexpensive. I flip-flopped with a couple different designs:


Option 1: pontoon style with a deck



Pros
  • more cargo area
  • can double a floating dock for the kids in summer
  • easy construction
Cons
  • slower
  • less maneuverable
  • heavier
  • more chance of seam seperation

Option 2: true flat boat design



Pros
  • single unit
  • more responsive when paddling through surf
  • faster
  • less time invested into construction
Cons
  • less cargo area (I will improvise by incorporating straps/bungees for lengthwise storage of fish)
  • less stable
I found a good supplier of billets with free shipping so I was stoked. Glassing would then be my next step, but I wanted something with more durability and dependability than fiberglass or resins. I decided to vacuum form the joined billets after the shaping stage. This way I can knock it out in one shot with sheets instead of trying to work it by hand and have to worry about curing times. Although it's unfinished, it should be pretty awesome once the painting and graphics are completed.


The final product comes in at 10"D x 40"W x 96". The hull has been planed to a 22° curvature much like a kayak. The deck is completely flat with a small covered hatch in the rear for small accessories such as backup knives, clips, water bottle, etc. I have also included 8 stainless steel eyelets for (4 opposite each other) for running bungee straps in a criss-cross formation like shoelaces. I currently use this method on a longboard modification that I did last year.
 

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No recent pictures on hand. I am amidst the shaping process. But again, if I give away the "secret sauce" then it's no longer secret. Let me see what I can do.

The whole concept is fairly simple however....flat bottom, flat deck with dugout hatch, hull rocker. Imagine a kayak of sorts without the confines of a cockpit and a few different variations
 

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Thats nice Kana, quite a big project.

I have a long ocean going surf ski for getting around on that, my float will be for shore dives so much smaller.
 
How do a surf skiis compare to Sit-On-Top kayaks? Seems like a similar concept.
 
Yeah similar concept I cant find any images of the type we have they are old so probably not made any more. I MUCH prefer them to those kayak things you see everywhere now though.
 
Hi guys - i'm new here and in the process of producing a float/board design in mass quantity. It will be made from the same material as a sit on top kayak - medium density polyethylene. production will be ready in about 3 weeks. it'll be rigged with straps galore, buckles, a nifty little piece of hardware to mount a flag. measurements 38" long, 22" wide, 7" deep. i live in stockton california. let me know if you want more details.
 

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Wow, Kana I really like your idea. Even that one you have in the pic is a nice design, which could be modified for spearfishing. Did you make that one yourself?

Some Questions:
1)What are buoyancy billets (what do they look like, what are they made of?
2) Are you planning on selling your design, that you are so secretive about it?

Wow, just looked up some stuff on DIY vacum forming, its awsum! I really wanna give that a try. If you where to make a machine big enough you could literally churn out a SOT kayak in 5 minutes useing nothing more than two sheets of perspex. I think i'll start with a small compartment float. Watch this space!

http://www.instructables.com/id/Make-a-good%2c-cheap%2c-upgradeable-sheet-plastic-vacu/
 
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Okay so I know I'm new to this fourm, but I actually have made 2 surfboards.
If you want to make the floatie thing, your best bet is going to home depot and getting those insullation sheets. The pink ones that come in the size of 4'x8'. The biggest problem with this, is you cannot use polyuarthane resin, because it will melt it. Your best bet is to use epoxy resin, like ss2000. It is VERY VERY durable if you double (or even triple) layer the fiberglass. Oh and go with multiple 8 oz layers (fiberglass cloth wieght/density).
 
I forgot to include that it is polystyrene that the insulation sheets come in. And glue the sheets with the ss2000. It will provide a bond that is nearly impossible to rip apart. If you really are considering it, here is a link to buy the right kind of resin to put your thing on http://surfsource.net/Manufacturing/Building Materials/buildingmaterials.htm. And if you want to be able to tie a string to it, I recommened using a surfboard leash plug, they're cheap, and would work great.

*I also meant 4oz cloth in my last post.
 
MrX,

Surfskis come in 3 types as I view them.

High performance custom skis - very tippy, but can be surfed verticle (by a few!). No good for spearo.

Pop Out "plastic" skis - stable, short.. - no storage. I've considered these before as they are cheap 2nd hand (£50 ish). They usually have a single fin.

Racing skis - long and tippy. I think you would have real problems with a weight belt!

South African style skis - These are becoming popular now. They are designed to fish from. A bit like a pimped ocean kayak. They are as heavy as the plastic tubs, as most have double hulls. , but fast and stable.

I've also considered the windsurfers board before. You can fine big boards for free. A bit of imagination could make a large platform to hunt from.

as it is I have an Atoll for most days and picked up a 2nd hand Seatec nautilus Float for £35. I've not used the Nautilus yet, but thought it was worth a go. Anybody else used one? It won't be my main float (to big to have in the van all the time).. but plan to use it for longer hunts between spots.
 

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hmmmm looks alot like what paradaxes is trying to build.

I know of quite a few different types of skis, Being a South African, i always wonder which one people are refering to when they speak about the south african style kayak. hehe

What is an atol?
 
Thats exactly what im doing fatcake

Oh and Lenny only got as far as gluing the sheets together , got distracted making a polystyrene cutter from wire and a car battery lol
 
small flat inflatable bouy. Storage for guns and drink, etc. Flares! .. But still nice and compact.
 

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Thanks for the overview Pav - excellent. I think it is the South African skis I am thinking of (featured in advertisements in Len Jones book & I think spearo Dave said he had one). Is that the same type Magnum PI used to race in Hawaii?!

Nautilus, is that the one Spearo.co.uk carry? Or apnea.co.uk? Looks great but I can't see myself carry it down to the beach - I rarely use my beloved solid 11 litre RA float (with flag & inbuilt ballast) these days - too big & heavy for any kind of walk in. Is that a full catamaran-style hull? Does that offer some advantage? I guess it is less to carry than the kayak or surf ski though. There are a couple of big inflatible floats too though, I recall one even has a window! (Sevylor Hunter?)
 
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I have been testing all kinds of floats recently, bodyboard floats, innertubes, etc. For me they all seem to have the same disadvantage: They all get tangled in the kelp and i end up spending more energy getting my float loose than I do diveing.

So I'm really begining to think, that i should ditch my floatline all together, and dive off a ski. It would also save me the frustration of getting my legs and fins entagled in the line. As well as letting me take a breather in between dives and easier acess to spots futher out.
 
I have heard that you can paint the pink foam or blue board with house paint first then use resin, wont melt then.

Jason
 
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