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vrijdag 6 november 2020

The final stand-alone mast system!

 Finally the one and only best way to lower your mast has been developed. By me 😀. It's an almost stand alone mast with no shrouds, except ofcourse one uphaul line. It all looks very neat, although the sail is on old stretched out Flat Earth-sail that can easily be replaced by a Falcon-sail or whatever. I normally use this Flat Earth for very strong winds because it has the least heeling force. Also the least propulsion but in stormy conditions that's just fine. 


Stand alone mast



                  



This is how it looks in a basic drawing: 





This mast pivots in an inverted sort of skeg box that resembles a quarter pizza box. This so-called stand-alone mast has no stays, except for the forestay to raise and lower the mast. A small but strong Dyneema line around the mast, attached to very strong points on the deck, prevents the mast from dropping forward when heading downwind. This short line also keeps the mast in check when lowered.

The seams have not been sealed yet.

Below is the end result. A close up of the plastic covered Dyneema line that keeps the mast upright and prevents it from falling over. The plastic tube and line within keep the mast upright and give enough room to lower the mast. so that you can slide the mast in or completely out while sitting in the cockpit. Very handy to fix something to your sail while on the water. You just pull the mast out from underneath the tube and it can be reached anywhere. Then slide it back, it's done. 
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Cons:
- Lots of work to install
- Rolling can only be done by releasing the sheet from its cleat, not by releasing the forstay (the mast will not fall sideways). Sculling up slowly followed by a high brace is the only option, unless you can roll very well (even with a mast that is still upright and a sail trailing through the water).
- The pizzabox takes up some space in the front compartment. You can only slide long, narrow objects along it, Such as a bag of tent poles.

Benefits:
- It looks very neat!
- No dangling lines on deck or along the sides of the kayak when the mast is stowed away on deck, so less chance of snagging.
- When down, the mast with folded sail can easily be pushed forward beyond the cockpit. So even more free space to paddle. You can therefore also use a longer mast with a DIY sail. 
- If necessary, the lowered mast can be fully pulled towards you to repair something from the cockpit. Then stick it back underneath the plastic tube and raise the mast again. The three dubble weaving of the small line back and forth through the strong deckrings plus the installment of the plastic tube ensures that it will automatically form an arch. So the mast will always slide through without bumping onto the tube. 


The standard system
Of course there is also the standard system of Flat Earth, Falcon and Sea Dog with a flexible tiller foot on the deck and rigging with many stays. The disadvantage is the limp rigging that dangles along your boat when lowered. Or the rigging that gets in the way during rescue operations. All these lines are a messy sight as well.



The well known system of Flat Earth with the tiller mastbase and all shrouds. 



So for a long time I was looking for an even simpler system without sidestays or even backstays, with a so-called stand alone mast. 
First I devised a pipe through the deck and fixed it to the keel with a block of epoxy. I soon found out that it's almost impossible to position the mast with sail flapping around while sitting in the cockpit on some waves right above the pipe opening to let it slide in. I made a sort of gutter/ chute at the opening of the pipe to make sure the mast wouldn't pop out of the opening while pulling on the forstay, but alas, the mast just stood upright but wouldn't slide down the pipe most of the time. Instead it would fall sideways of forward within seconds. The next problem was lifting the whole darn thing upward in order to lower the mast.  Oh Lord, help me!

That's why I tore the whole thing out again and thought of a much better plan. I now have made a wooden type of skegbox in the shape of a quarter circle (think of a quarter pizzabox) with the opening facing up through the deck.

The quarter 'pizzabox' in progress. Made of steam bent plywood and laminated with polyester and expoxy. The opening will surface flush through the deck.


So in the deck there is a slot in which the mast can turn up and down. A single forestay is required to raise and lower the mast. And to keep the mast upright in the box while paddlesailing, especially on a down wind course.  

The hinge for the mast consists of a strong but thin Dynema line that runs through two flat D-ring mounted on the deck and runs forward around the mast to hold it up. This line prevents the mast from falling forward and also keeps the mast in place when lowered. A normal steel hinge with hard protruding parts is out of the question because rescuers doing an X rescue would scratch their own deck on such a chunk of steel. 

Placing the box is no sinecure. The bottom of the box is again cast in epoxy - just like the pipe - for which a container is first made of two plywood partitions that fit on the keel and a few inches upward against the sides of the kayak. This will act as a container to poor in the epoxy. Don't forget to apply some bubbling glue along the seams or duct tape, otherwise the epoxy will oose out. The box is then laminated to the slot in the deck. All in all, this cannot be done from the manhole. It's too far back to reach the whole work of art. That's why I cut out quite a bit of the deck with a grinder. Than I laminatd the box on the bottomside of the deckpiece and placed the entire construction back in place with the bottom part of the pizzabox sinking into the container filled with epoxy. 


This hole looks bigger the in reality because of the optical illusion caused by the camera lens. The old base of the pipe is still visible. I grinded and chiseled it out later on to make room for the pizzabox. 

Finally I closed the seams around the deckpiece with polyester and epoxy and sanded it flush. This can be done from the manhole. I didn't apply any topcoat. You never, ever get the colour right. Besides, all the seams were to be covered with keelstrip. ,This gives the whole construction a steardy 'designed' appearance. As if the kayak manufacturer built the boat this way.

My 'invention' isn't entirely new. In fact, this system is as old as Methuselah. Copied from the old Dutch tjalks and clippers that often had a stepped mast to the bottom, although with additional stays. When lowering, the bottom of the mast turned through the deck. This bottompart had a counterweight so that the skipper could lower and raise the mast with one fingertip. The slot through the deck was sealed with a cover plate wedged in place. In my case, I just leave the slot open. Less than half a liter of water goes into the pizzabox.

Of course, this system is impossible for the novice kayak sailor who buys a ready-made set and wants to sail immediately. Yet I firmly believe in the simplicity of an upside-down pizzabox. It saves a lot of junk on deck due to the lack of two sidestays and two backstays. It all looks a lot better. In the future, I hope a manufacturer can make a ready-to-use plastic pizzabox with a flanged rim that extends over the deck. This edge can be glued or bolted. A few wedges in the bottom of the boat will also hold the box down below. That saves a lot of work and you do not have to grind open part of the deck to access it. 

Perhaps this system is worth incorporating into a new kayak model with pre-molded inverted pizzabox in the foredeck. That would be the first kayak that is specially designed for kayak sailing. So not an ordinary kayak that will be tinkered with afterwards. 

A ready made version in plastic could look like this (below), with a flange that fits on any deck, bolted down with rubber kit in between as a sealant. It wouldbe a lot easier than a wooden box carefully laminated to the deck, like I did.







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