Folding Kayaks Forum

Some thoughts, observations and ideas from a novice

The "Superior" has a single port inflation system. This is the only difference from the standard. When locked, the sponsons and floor are isolated as three compartments (I hope!). This works pretty well for inflation/deflation, but the mechanism needs some work! The device sits in a fabric hole and would be better if it didn't "float" but was fixed to the fabric covering.

The boat folds into a waterproof (backpack) bag. The fabric may be waterproof, but you can see through the stitching. So not to be relied upon. The bag holds the boat, 3 seats, and I also include, two pair of wet shoes, 2 PBA, hand-pump and hose, a painter c/w 3 carabiniers. The bag is supposed to hold the folding paddles too. I have managed to fit the short ends, but there is nowhere to sensibly carry the long ends. All up, this is not too bad to carry a few 100 metres (not tried further).

Inflation with the double acting pump is a good work out! I understand that a foot-pump is easier. After a couple of trips I started looking for an electric pump - not cheap! I found a 12V "airbed pump" for £6 at a local store, added one of my Drone LiPos and a 12V accessory socket. This gets me inflated in about the same time with no work! Deflation is also very efficient. Once inflated, I add a few puffs from the Hand pump via the supplied manometer. The manometer does not zero and I believe that the recommended 1.5psi is too low since the sponsons buckle.

The seats inflate and are suspended from the sponsons. The idea being that you do not deform the floor with your fat butt! since the seats are suspended above the floor. They are not, but sit on it! This idea IMHO is something that could be improved upon (see below).
The seat positions can be adjusted and are marked out for 1, 2 or 2+1 persons. This is NOT a three-man boat, but 2+child. Having said that, the first outing had 3 adults, and a small dog aboard. I'm 6'4" and 100kg! Cramped and low in the water! A pig to paddle. Two up and one up it's a joy!

It is stated that the attachable skeg can be left off for shallow water or white water to give clearance and more manoeuvrability. Nonsense, with two up you have no steering authority and the boat will suddenly 'head off'! We cut a trip short because of this, having bent the skeg and so it was not used.
So that the skeg wasn't forgotten (you have to fit it pre-inflation), I folded the skeg up with the boat. A couple of hot days in the car, and it now has a bend that I cannot remove! New one purchased! (my son is scanning the old one, and I'll make a modified deeper, longer skeg as an experiment.) So keep your skeg flat!

We find that launching from a bank makes entry a little tricky, especially on canals where there is no portage for the locks. Very low banks and slipways are simple, but sometimes the drop is about 1M.
I added a new mod this weekend. It consists of a 9mm ply 'floor' it is shaped at each end (wife thought I was making her a coffin) and edged with garden hose to prevent chaffing. It's about 1.7M long (fits inside the car). This is a great improvement and you can stand in the boat like a SUP! The boat rides better and feels quicker. The only downside is that it is slightly higher in the water and so slightly less stable. The boat is otherwise very stable in my opinion.

Birthday! My son announced he has bought me an electric outboard - looking forward to it arriving!

If anyone would like pictures of the air pump lash-up, or the floor, let me know.
I hope the above is useful and would welcome any comments.

Regards
aDub

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If you've thought of something daft, an idiot has already tried it!

The floor mentioned above works really well.
It's made of hardwood 9mm ply. I didn't bother with marine ply, since it's very expensive for an experiment and to be honest, if you don't treat/waterproof the edge of the plys, it's going to fall apart anyway!

Disclaimer: Follow at your own risk; eyes, fingers etc. are useful and difficult to replace. Always check yourself before you wreck yourself!

I purchased an 8x4 board (select for best quality) and had the store (Bunnings) cut a piece 480mm wide along the long edge (check the width required for your craft). They offered a free service of 5 cuts. This meant that I didn't need my table saw/panel saw, and I could get both pieces in the car
I spent a long time with the kayak deflated and the floor exposed, deciding upon the position and size of the floor. The original sketches called for fancy curves (see the image for dimensions used)

Remember: measure twice, cut once!

Once marked, I covered the pencil lines with Sellotape and burnished with my thumbnail to ensure a good hold. The tape helps to prevent break-out.
All cutting was done with a home-made frame saw and a very cheap fine Japanese kataba style draw saw. Let the saw do the work! This type of tool makes cutting straight and square very easy, even for a novice. You can of course use any cutting device you like.
After cutting, I ran a plane down to "break" all the edges (glass paper with a backing block will do) This reduces the chances that the wood will splinter.
A quick sanding with fine glass paper was followed by de-dusting with a slightly damp cloth
Yacht varnish was carefully applied to all edges, taking care to fill any voids (these should be filled really!) Once touch dry, the whole board was varnished on both sides. Apply as many coats as you like following instructions.

Edging is made from some cheap garden hose, it's purpose is to protect the fabric of the craft from chafing. I did this as follows...
Cut a length long enough to cover both sides.
Lay the hose out to remove any kinks and twists. We do not want a spiral cut!
Using a craft knife, blade-up I pulled it toward myself, keeping the tube lined up. BTW a little wetness in the pipe helps lubricate the cut. Cut a short distance, check alignment and cut again. There are probably extruded edgings available that could be used.
Take a cloth and dry the tube
I used superglue to fix to the board about every 150/200mm paying attention to the ends. I have allowed a little overlap to cover the corners, but have not yet decided how/if I need to finish the ends.

Note that the finger holes for carrying have not yet been implemented (I created them in the graphics package). I intend to add several, along with some holes in the floor to lessen weight and allow areas for attaching bindings. Note also that the image is somewhat distorted by the camera, I should alter that in the graphics!

Fitting: Very simple, lay out the kayak and pull the sponsons to the side, fit the board where required and inflate!

Note that the overall size is 480x1930


Larger image here

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If you've thought of something daft, an idiot has already tried it!

I don,t have inflateables, just Klepper and Folbot. But I am interested in your outboard and in your adaption, plus of course the make of outboard and performance. It,s an idea I have been looking at for some time and found the best batteries seem to be lithium, but expensive, the more traditional batteries weigh from about 30lb to give decent endurance.

Hi John,
I have literally just received the CAD files from my boy who scanned the boat the other day, so I'll take a look at those and see if I can improve my freehand design (difficult to measure/design from a 3D boat!).
A lash-up will probably be much easier for you on a solid boat.
The intention so far is to have a ply plate over the stern holding the transom. This will be held in place by the rear handle and some form of wedge and then forward fixings will be straps to the seat-fixing webbing.
The unit is a Haswing 20lb trolling motor As I say it was bought for me. I was having a conversation about using a ducted fan brushless motor that I could hold over the side in my hand. So no real thought has gone into this!
As to power, yep hungry and would probably be more efficient with a PWM speed controller. I have the option of a 120Ah Car battery (not deep cycle), or thinking of making a unit where I can parallel up some of my LiPos. as you say expensive to buy for the purpose! However (especially with an intelligent controller), you won't need a high C device C10 rather than C60 would probably do.

I've spun the unit up in the air using a LiPo. Nice and quiet. I have noticed that the resin(?) transom clamp flexes quite a bit when tightened, and so will take that into account when making the transom.

Could be fun!

I took some more images of the floor in the boat yesterday (Congresbury Yeo) so will post soon.

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If you've thought of something daft, an idiot has already tried it!

Silly afterthought. If you want to give it some beans, then a bush-wacker with a flexible drive shaft! Oh yeah, and keep the blade on to deal with weeds before they hit the prop!

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If you've thought of something daft, an idiot has already tried it!

This is the raw CAD model of the stern taken from a scan using a 3D hand scanner. Showing part of the floor, sponsons, rear apron, inflation port location, and the cover for the inflation system (vertical cloth wall)

Beats tracing the real thing! BTW, this is just a quick rough and ready render, so the definition isn't great!

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If you've thought of something daft, an idiot has already tried it!

Well, I've had an initial play and this is a rough. The slot will take the rear handle and maybe attach via a cord and cleats This secures the rear. The front can be attached to the seat webbing via adjustable straps, maybe using a spring layout. The motor I have can swivel/lock for steering, but without this, the strapping could adjust trim.

All ideas accepted.


overview - don't look too closely, I'm using an unfamiliar CAD. Round holes to accept forward strapping. The 'vee' leaves access to the inflation point and access to the rear stowage area (battery pack?)


detail of pockets for the clamp in case of loosening, The slot will accommodate the handle. Maybe cleats on the ends of the transom?


detail of underside. Transom glued and screwed

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If you've thought of something daft, an idiot has already tried it!

More floor!

Floor in, waiting for air!


Inflating. Notice my air pump and LiPo battery. Just needs a few pumps with the hand pump and manometer to finish.


Waiting to get wet. Notice the light under the seats. This goes once you sit down and the floor is compressed. May work fine for a child.

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If you've thought of something daft, an idiot has already tried it!

Been a bit busy for any CAD work, but thought I would get the pump details out.

As mentioned I was finding the double-acting hand-pump a lot of work, and looking at portable electric alternatives, I thought that they were far too expensive.

So I found this in Aldi, six quid!

As you can see, a lot of work has gone into aesthetics! It has 3 nozzles that work for inflate or deflate and a long lead with a 12V accessory plug. The label says
Adventuridge Model HS-198A Electric Air Pump
12V 75W
Air Pressure Max ca. 47mBar

For power I happen to have LiPos about, but even so a 5A 20C (100A max pull) can cost £20 or less see here

If the output of the pump was higher, it would be worth adding a pressure sensor and a small processor (Arduino nano with a relay?) to make it auto shut-off. But then I'd need to make a box too!

If new to LiPos, ensure that you get a balance charger. Like many things, there is a great deal of BS floating about the web when it comes LiPos (much of it on regarded websites!), and it's true, you can almost kill them with a hard stare, but if treated with respect they will give a long life. This care especially involves charging/discharging. This page is useful, but he's selling them so pinches of salt!
You can of course use any power pack you like - D Cells would probably be fine.

This is my power kit

I keep it all wrapped in the grey towel in a waterproof drawstring bag (to protect the LiPo from knocks and wet).
Notice the "low voltage warning device". This emits a (very) loud beep when the battery hits a preset low voltage (used on drones). It also displays each cell voltage and total voltage. It connects to the balance charge lead and is well worth nearly £2!
I knocked up the accessory connector rig with a bit of silicone covered wire and covered the joints in heat-shrink. It should realy be in a box. I may find a suitable sandwich box to fit.
Excluding a charger, the whole lot is less than 1/2 the price of a cheap commercial unit, even if you include a battery. Be aware that LiPos come with a range of possible different connectors, the more common being TXnn, 4mm bullet, and deans connectors. Check first before buying the opposite end!

This setup works really well for inflate and deflate. It's about the same speed as using a double acting hand pump, but zero sweat!
My kayak is supposed to be inflated to 1.5 psi and so I give a final few pumps on the pump (6 max!) using the supplied manometer. I don't use the hand pump at all to deflate.
The pump is not too noisy and not at all irritating to other people; nobody looks over to see what's making the noise.

£5.99 well spent!

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If you've thought of something daft, an idiot has already tried it!

(see above) If you've thought of something daft...
https://www.instructables.com/id/Weed-Wacker-Powered-Raft/

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If you've thought of something daft, an idiot has already tried it!

I have now had a few minutes to get back to my "flying V" transom design. The idea is to have a system that leaves the kayak itself unmodified. I could stitch or stick fittings to the hull, but decided against that, especially since the boat is under warranty.

As mentioned above I'll use the stern grab handle to attach at the rear. I intend using two wedges that will act between the transom deck and the handle, each secured with a cord and cleat. The wedges will sit side by side, and together with the "foot" should prevent them from rolling and so losing tension. They could have clamping a cord between them if this is an issue. They need to be inserted easily and so a fixed pivot/clamp may not be practical and increases complexity.



By levering up from each side of the handle this should impart lateral stability as well as clamping the deck to the kayak.
If the weather improves today, I'm torn, set out on the water or make the transom?
I'll not add any dimensions until the unit is made and tested. Although the motor is quite light and the power quite low, I have added "cheeks" to the sides of the transom to improve strength and rigidity. Room had to be left for proper access to the clamp hand-wheels and the transom may need to be taller. Since the wedges will also imped the clamps, they must be fitted last.

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If you've thought of something daft, an idiot has already tried it!