Bestevaer 49ST

[noelex 77]

Originally Posted by mickeyelam

This system sounds secure, but I'm concerned about emergency egress if padlocks are part of the system.

Yes, good point.

It is also important to be able to exit from a number of locations easily in the event of an emergency such as a fire. I don't want to go into too much detail about our systems, but both these things have been taken into account.

Most of the favoured cruising grounds are very safe. The people we have met cruising have been very honest and trustworthy. I don't think we need to be overly concerned about problems, but long distance cruising boats sometimes need to at least pass through areas where crime rates are more significant.

On many boats the security system is so woeful that there is little point locking up at all. Often there is no provision for security while sleeping at night, especially if some ventilation is needed. With some simple steps it is easy to make your boat comparatively a much more difficult target and hopefully the thieves will be persuaded to go elsewhere.

The improved security was only a small aspect of the design brief, but I hope these details, which differ from most yachts, are of interest.

[Panope]

Originally Posted by noelex 77

The improved security was only a small aspect of the design brief, but I hope these details, which differ from most yachts, are of interest.

I wonder if KM will make these features "standard" to thier line?

Steve

[weavis]

Originally Posted by noelex 77

Yes, good point.

It is also important to be able to exit from a number of locations easily in the event of an emergency such as a fire. I don't want to go into too much detail about our systems, but both these things have been taken into account.

Most of the favoured cruising grounds are very safe. The people we have met cruising have been very honest and trustworthy. I don't think we need to be overly concerned about problems, but long distance cruising boats sometimes need to at least pass through areas where crime rates are more significant.

On many boats the security system is so woeful that there is little point locking up at all. Often there is no provision for security while sleeping at night, especially if some ventilation is needed. With some simple steps it is easy to make your boat comparatively a much more difficult target and hopefully the thieves will be persuaded to go elsewhere.

The improved security was only a small aspect of the design brief, but I hope these details, which differ from most yachts, are of interest.

You raise an important point in yacht design. Their is a collective approach in the design of a vessel to NOT make it very secure. I have been really disappointed in many catamaran designs for this reason. A boat MUST be able to be secured when the crew is absent.

[noelex 77]

Solar installation:

Solar will be the primary means of electrical power generation. The reliable, quiet power that solar produces is hard to beat.

Our first yacht only had 46w of solar and we happily cruised for many trips over a month with this as our main means of power generation. In those early days solar panels were very expensive and the only solar controllers were those that you made yourself. We could have never ever imagined having over 1000w with multiple MPPT controllers.

Our new system is three Sunpower panels controlled by three speperate Victron 100/20 regulators feeding a 600 Ahr 24v battery bank. The reasoning behind the controller choice can be see in post #1516.

The controller installation is in the technical area/workshop. It is great to have a workshop on a cruising boat, but the other advantage is equipment such as the solar regulators, autopilot, inverter etc etc can be mounted in this area. As it is not part of the regular interior, the equipment does not need to be hidden away or flush mounted. Wiring can be exposed without looking out of place.

This makes for easy installation and troubleshooting. Equipment can be easily replaced by simply bolting it in place and if the new model is a slightly different size the discrepancy is not a problem. As the equipment does not have to tucked away in cupboards or under benches, ventilation as well as access is improved.

This is the solar controller installation:

Many people install MPPT contollers with little considerion of the heat they generate. Particarly with models without any active fan cooling (such as the Victron units) this can have have an effect on reliability. As a general rule, rigid solar panels are incrediably reliable, but MPPT controllers are a common failure point. Having three controllers helps redundancy, especially as the controllers are deliberately underated so that one controller could service two panels if a failure were to occur.

Underating the controllers also helps the units run cool, which is helpful for reliability. I have installed the controllers a reasonable distance apart and mounted them on a aluminium profile. The aluminium profile primarily allows the wires to be fitted behind the units to fit neatly, but is also adds some extra space for airflow underneath the heatsink of the controller. I added some thermal conductive paste to the joint between the aluminium profile and the heatsink of the solar controller, so the profile should add to the heatsink surface area.

The two electrical boxes above the controller house three double pole circuit breakers for inlet. 60v side on the right and the 24v outlet side on the left. Circuit protection on the inlet side is recommended by the solar manufacturers. It can be argued that the current on the inlet side is self limiting so circuit protection here is unnecessary, but it is nice to have the ability to isolate the inlet side of the solar input, especially when this is 60v. It is easy to underestimate the dangers of the high DC voltages.

The central black box is part of the Pico battery monitoring system. The black box wilł report the output of each of the solar panels to the battery monitor.

[john61ct]

Very well thought out, especially the 1:1 SC to panels, and redundancy without spares.

Originally Posted by noelex 77

three Sunpower panels

Link please?

[noelex 77]

Originally Posted by john61ct

Link please?

The panels we fitted three x21 335w black:

https://us.sunpower.com/sites/sunpow...ac-modules.pdf

Sunpower have now released 22% efficient panel producing a few more watts per unit surface area. This is a help with the limited surface area available on most yachts.

[john61ct]

Interesting, did you just disable or bypass the built-in AC inversion?

What are the Voltage specs as DC output?

[DDabs]

Sweet solar setup. Can't wait to see more photos of the arch with panels.

[noelex 77]

Originally Posted by john61ct

Interesting, did you just disable or bypass the built-in AC inversion?

What are the Voltage specs as DC output?

Sorry. I did not look at link close enough. Our panels are the x21 335w model but without the built in inverter. So they just produce DC.
Here is a better link:

https://us.sunpower.com/sites/sunpow...lar-panels.pdf

[noelex 77]

Hatches:

Boat hatches have several seals that need to stay intact to maintain watertight integrity.

There is the seal between the hatch frame and the deck. The seal between the hatch frame and rim of the hatch lid. There is a seal between the perspex and the rim of the hatch lid and also there is the seal between the hatch handles and the perspex.

Multiply this by say 10 hatches and there are many potentials for leakage. Salt water inside the boat, especially if can soak into the foam of bedding or cushions, is the pits. Even if you can dry out the foam, the salt remains and bedding feels constantly damp and musty.

The seals can be replaced, but our experience is that you only discover a leaking hatch when offshore with green water over the deck.

The second problem is that perspex hatch lenses degrade, especially in areas of high UV exposure. Replacing the perspex is surprising expensive and is a time consuming job.

KM accepted the challenge of building a hatch that would be waterproof even under considerable water pressure and would retain that watertight integrity over the long term.

We wanted submarine hatches .

The solution involved a solid aluminium hatch, which has much less flex than a normal marine hatch. The hatch handles are thick stainless steel rather than plastic. There are 4 handles per hatch, together with two adjustable hinges that allow for high and even pressure on the seal, especially when combined with the thick aluminium. The hatch base is welded onto the deck, reducing another potential leak source.

The hatches have been raised 50mm above deck to reduce the pressure of green water on the seal.

A bonus is that the hatches are insulated, reducing condensation. Most of the hatches are solid aluminium with an insulated interior. They do not let in any light other than when open, but the large pilothouse design lets in plenty of natural light.

In the owners' cabin we wanted a view above our heads to see the night sky. This area is far enough away from the pilothouse to need some natural light. Rather than a perspex insert, hardened glass has been used. Crazing in areas of high UV, and significant scratching are largely eliminated with the use of thick glass rather than perspex. The clear insert requires a seperate seal, but this has been engineered to be much sturdier and more leakproof than a normal hatch seal.

Combined with a deck that has no penetrations into the living spaces (everything is welded in place or tapped into reinforcing plates), our goal was to achieve a boat that is truely leakproof even in rough offshore conditions. Time will tell if KM have been successful.

The hatches have also been fitted with removable security bars. These enable the hatches to left open with some security on those hot nights when going ashore for dinner or visiting another boat. For the ultimate security, when closed the solid aluminium hatch and stainless steel handles make forcing open the hatch much more difficult than on most boats, and hopefully discourage the bad guys.

KM produce some wonderful engineering. At the recent Düsseldorf boat they displayed a completely retractable hydraulic drive that has been made for a 24m yacht. The yacht is designed for polar exploration, and could freeze in the ice, potentially damaging a conventional propellor system. I think they considered our custom "submarine" hatches an easy challenge by comparison.

[DDabs]

Wow- awesome stuff on the hatches. Thanks for that post

[Van Der Beek]

That is robust, and I like the industrial / bare mechanical look.

[noelex 77]

Shower:

We wanted a dedicated shower. It is constructed simply as a waterproof aluminium tub with a high lip on the door. The aluminium walls are welded, so they function as very deep ribs just in front of the chainplates. Bulkheads on aluminium boats are non structural, but by making these bulkheads aluminium it means they add some bonus rigidity.

There is full standing headroom in the shower, but it is helpful to have a seat in a boat shower. Our seat is anodised aluminium and is hinged with three laundry sized sinks below. Above the seat a very stout, removable anodised rail can be positioned at a couple of heights. The rail can be used to wedge yourself into the shower, like the safety bar that is used on some amusement rides. This leaves both hands free if you want to use the facility in rough offshore conditions, especially on the "wrong" tack. The rail is also for ease of wringing washing, allowing it to dry more quickly. As well it functions as a long, sturdy hanging spot where wet weather gear can be left to dry with the water dripping into the tubs.

We have a washing machine installed in the toilet area, but these devices receive mixed reviews from cruisers (we have never owned a boat with one so it will be a new experience for us). Having good facilities for washing clothes by hand is a nice back up. Large sinks are always useful on a boat and in a shower are a better use of space under the seat than storage, which is very hard to keep dry and mould free in this area. Of course, items such as shampoo etc can stored in one of the laundry sinks.

The shower is fed from the main water supply, but there is also a seperate pump and shower rose that functions differently. The supply to this feeds from one of the sinks rather than the main water tanks. The technique is to pour hot water into one of the sinks then add some cold until the shower water is exactly the desired temperature and use the inbuilt pump to shower with this water. It is a showering method that we have used for many years and it works very well on a boat. No water is wasted while you adjust the temperature. The water can be heated from any source or mixture of sources such as solar (just leave a black container on deck) , the Reflex diesel heater or the propane stove. The temperature can be mixed so it is exactly correct and you can shower anytime even if the engine has not been run for several days. I am fussy about shower water temperature. Lukewarm showers in cold climates. Yuk. It is also possible to shower with different water from that stored in the main tank, which can be useful if there is ready supply of water of questionable quality. We will have a water maker, but a back up plan is always a good idea.

Most boats fit a mini version of a household bathroom, I suspect because this is what the boat buying public are familar with. This looks attractive, but is not enormously practical. The area can be difficult to use in rough conditions without spilling water in places where it is difficult to clean, especially when the space is out of necessity small. Even getting undressed out of wet weather pants while heeling over without a few bruises can be a challenge. On many boats spilled water from the area can also find its way into the general bilge and unfortunately grey water tends to be a bit smelly after some time.

Our shower is a little different. The concept was to construct an area that was simple, functional, waterproof and easy to clean. It was inspired by the type of shower that may be seen on a workboat, such as a modern fishing trawler. Surprisingly, with the plain white walls anodised aluminium and the beautiful timber on the door, KM have managed to make the area attractive.

This space is difficult to photograph, but here you can see the anodised shower seat and removable rail in one of its positions. There are large laundry sinks below this.

[GARRYOWEN]

Amazing.......fascinating shower information and design. Thanks for the update, I know you said it's difficult to photograph but if you come up with more shower pics I'd love to see them !

I never had a boat and I'm just dreaming but I certainly never considered all those factors you brought up....You are gonna have some kind of great boat when you're done !!!

[Pete7]

Originally Posted by noelex 77

but there is also a seperate pump and shower rose that functions differently. The supply to this feeds from one of the sinks rather than the main water tanks. The technique is to pour hot water into one of the sinks then add some cold until the shower water is exactly the desired temperature and use the inbuilt pump to shower with this water.

What a clever idea :-)


Pete