For the very latest activity, click here: From a Bare Hull

Saturday, July 28, 2012

Main Salon Portlights: More Ideas

Here is the latest design on the main salon portlights. This version maximizes lighting by maximizing area. It has the traditional W42 dead light style with a twist: aft light is a mirror of the forward light with the sloping edge. The lights can be slide opening to provide ventilation.

Construction

Thoughts include having custom portlights made by Diamond SeaGlaze of Langley B.C.. These guys make quality custom windows any shape for yachts big and small, production and one-off. One DSG style being considered is a medium duty split-glass slide-opening portlight (D15). These lights are framed with 6063 aluminum that can be anodized/powder coated to any color. Except stainless, which will be the rest of the lights around the boat. It might cause a little "visual clashing" but for a quality window like this, I think I could live with it. Besides, custom windows in the main areas with traditional portights around seems to be common on many sailboats.


Monday, July 23, 2012

Final Floors: Part I

The current floorboards have been around since the early days of the project (once floor supports were installed). They were cut from cheap non-marine grade C/D-X plywood, and have been trimmed/cut over time to accommodate things as the build evolved. Included in that evolution was the addition of dirt, paint and resin drips.
Nice clean boards in the main salon
This last weekend I cut the final floor boards for the entire boat. This time with marine grade B/C 3/4-inch plywood. Care was taken with close measurements to ensure a good fit. Though these are the final boards, the floor is not "finished". To protect the nice clean smooth surfaces of the boards, everything has been covered with a couple layers of cardboard and masking tape.
Main salon floor protected with cardboard

Next Steps

The expected finish of the floors will involve
  • the lamination of a finished hardwood 1/4-inch plywood panel (species undecided at the moment)
  • cutout of under-floor access hatches/hardware installation 
  • final glue-in/fastening

On Finished Hardwood Plywood Panels

I like the traditional look of teak/holly strips (the admiral does not care for it). You can get this in a plywood sheet, though it is quite expensive.

One species under consideration is Bamboo.

More to come.


Monday, July 16, 2012

CNC Table Resurface

In preparation for looming finish work on the Westsail, the CNC table is having a new surface installed. Often called a "spoilboard", it is a sacrificial surface. Slight variances in router bit height, material thickness and plain old operator error, will cause the router bit to cut into the table at tiny depths. Over time, due to these cuts, the surface becomes more uneven, causing further variances in bit height, and so on.

So it is time to replace the surface to gain back some accuracy and consistency in cuts. Of course the nice thing about mechanized processes like CNC, is you can "dogfood" new parts for the machine, with the machine itself! A new table surface is a good example. Here the machine is cutting the zones for the vacuum plenum of the new surface.

Cutting the new vacuum plenum

When the time comes to remove the old surface, the machine will also assist. I will force the machine to cut through the old surface, cutting into smaller pieces to make for easy removal. The machine helps to repair, as well as destroy itself!

Thursday, July 12, 2012

Domestic Water Distribution: Forward End

Somehow, I always imagine a space as being bigger than it really is. I am sure there is some psychological term for this. Maybe it is optimism, but that term most certainly does not fit the rest of me.

I have had this space underneath the floor of the forward salon designated for pluming of the domestic water system. That includes: water tank feeds, pumps, filters, strainers, tubing, and distribution valves. The final distribution valves have been waiting on a special order from SeaTech, maker of these handy and inexpensive 'slip on' hose and fittings (no hose clamps or barbs!). One of the special order items was a custom built manifold to distribute three hot and three cold destinations. Now, their catalog does not give dimensions, so I guesstimated the size of this thing and carefully planned the placement and any extra parts I needed (tees, elbows, etc). Of course, when I had the manifold in hand, I discovered it to be too big.
Top: manifold. Center background: tank valves. Bottom foreground: pump strainer.
The first step in finding a solution to this sort of problem is, again, to stare at the space for about an hour (reggae music on the iPod seems to help). The solution is constrained by two requirements: accessibility, size of access door. The the original design sought to make all this stuff accessible through one trap door in the floor. Water filter access is particularly important as they may be changed frequently. The filters are bulky requiring plenty of wiggle room to unscrew and remove the cartridge bowls. The original plan had things laid out horizontally. In order to get everything to fit, the final plan has things placed vertically. In the end, this is a better solution as the valve assembly could be made more compact. The final plan did not require any extra fittings! 
Bottom left: one of the water filters (red button).
This valve assembly controls water for the forward end of the boat. Later, a similar but smaller assembly will be installed in the engine room to serve the other end. There are primary large tubing (22mm) for hot and cold water running between this space and the engine room. As of yet, we do not have a hot water source, so for now the cold water main line makes a u-turn into the hot water main line.
The whole enchilada
As there are no plumbing fixtures installed, the tube ends were capped with stopper fittings. After everything was fitted, the pump was connected and power applied for a pressure test. There were a few leaks where fittings were not fully seated around the tubing. All easy fixes. I had hopes that some day, this space may hold a modular water maker, but, I am pretty sure there is no more room. Oh well.


Still to come: aft end fresh water distribution, and raw (sea) water distribution

Monday, July 09, 2012

Distributed Power Trick: Battery Box Ventilation

Here is a trick one can do with a distributed power system that otherwise would be difficult, if not impossible, with a traditionally wired breaker system.

Battery Off-Gassing
A regular lead-acid wet cell battery can generate some gas during charging. Even under normal charging conditions (a good battery and proper operational charger) the batteries can give off a bit of hydrogen gas. If the batteries are in poor condition, or worse, the charger is malfunctioning and attempting to "overcharge", large amounts of hydrogen and oxygen gas can be released (electrolysis of the sulfuric acid electrolyte: why the addition of water to batteries is occasionally needed). A battery can also emit hydrogen sulfide gas (rotten egg smell) if overcharged.


In a well ventilated boat, such off-gassing is not a problem. Even volatile hydrogen, being much lighter than air, will dissipate quickly and is not likely a danger. But if the battery box is confined and sealed, the build-up of such gasses within the box can be a concern. Also, batteries tend to heat up when being charged. So, to keep things cool and to avoid any kind of Hindenburg-like event, forced air ventilation of the battery box is a good idea.
Well sealed battery box lid
Draft Assist Fan
This is the case with the Westsail: the battery box, located under the floor in the main salon, has a pretty tight fitting lid. Under normal conditions the box and lid will be bolted down snug to minimize shifting and movement with the boat. The box lid has two vent holes cut into the top. I want to add a draft assist fan to help draw air through the box. Ok, easy enough. But, the fan only needs to switch on during charging, and I don't want to have to remember to turn the fan on/off when the charger switches on.
24volt 0.1amp ignition protected draft assist fan
Distributed Power Control
Here is where the Mastervolt distributed power system can help. Control of the draft assist fan (on/off), can be switched by the power system in response to certain events during the battery charge cycle. Chance of off-gassing and temperature increase is highest when the charger is in high voltage "bulk" or "absorption" modes. The ChargeMaster 24-30 battery charger, signals such events so the power system can be programmed to switch the draft assist fan in response. When the charger enters "float" mode (a maintenance mode that keeps the batteries topped up) the voltages are normal, there is no off-gassing so the fan can be switched off. The event programming goes something like:
Programming the Battery box vent fan to respond to events from the battery charger.
Turn Draft Assist Fan ON when:
  • charger is turned on
  • charger enters "bulk" charge mode
  • charger enters "absorption" charge mode
Turn Draft Assist Fan OFF when:
  • charger enters "float" charge mode:
Other Charge Sources
But what about other charge sources? In the future, there will be an engine alternator, maybe solar panels, maybe a wind generator. The same hazards exists when charging from those devices. Well, the MasterShunt device, which holds the main circuit fuse and measures electrical current, also measures voltage. The MasterShunt generates events similar to the battery charger, except that there are no charger specific events like "bulk charge" or "absorption charge". It does generate an event when voltage increases to charge levels ("charging"). This can be used to turn the fan on. For turning off the fan, there is a "battery full" event generated when no more charge can be supplied to the batteries, or is '100% charged'. 



Turn Draft Assist Fan ON when:
  • shunt detects 'charging'
Turn Draft Assist Fan OFF when:
  • shunt detects 'battery full'

Programming the Battery box vent fan to respond to events from the master shunt.
Configuring the fan control this way allows it to respond to ALL charge sources, not just the battery charger.
As far as which configuration to use, the latter is best to accommodate all charging devices (alternator, solar, wind). But there is no reason we cannot have both, the system allows it.


And there you have it. A "smart controlled" battery box fan requiring no human intervention. Try that with your traditionally wired boat!

Thursday, July 05, 2012

Distributed Power Switch Box Placement

Here is yet another thing that changed from plan once I got the bits in hand: placement of the switch boxes. There are the devices that, when instructed by events on the network, do the actual switching of the target devices (lights, pumps, etc).

In the engine room there are two switch boxes: one for 24VDC and one for 12VDC. Each box can switch up to ten devices. I wanted an easy access location for adding new device wiring or overriding fuses, yet out of the way for "normal" operation. The solution was, as with the remote battery switch, to "hang" them on a custom cut acrylic bracket bolted to the backside of the aluminum panel frame that spans the width of the engine room. This puts the switch boxes at your fingertips when sitting at the workbench, yet it is recessed out of the way such that wires or lines of any sort can't get caught on the unit. Wire from device loads, as they are added, will route behind this assembly, against the hull with the E-Board, then drop in from behind to terminate at the switch box. In the future there will be an easily removed protective front panel across the bottom that will help protect the devices.
Switch boxes lower center and left. Battery switch lower right. User interface components center.
 Another switch box is located in the forward salon under the floor. This will serve the loads that will be atop the main mast (navigation lights, anchor light, deck/spreader lights, etc). The wiring for these devices will exit the base of the mast, down the inside of compression post to the step underneath the forward salon floor, to ultimately terminate at this switch box. The box will also switch the fresh and raw water pumps for the domestic water system nearby, under the same floor.
Mast step switch box.
The mounting of the switch box is temporary for now. I need to come up with something that helps protect the device from moisture, yet provides easy access. I figure I will address that when the final floor is installed.

A few more switch boxes are planned throughout the boat. They will be added as devices continue to be installed.

Monday, July 02, 2012

Engine Room Component and Wiring Access

The installation wiring of the Mastervolt components provides an opportunity illustrate the mounting system devices for the engine room.

Large-ish components, such as the battery charger and DC-DC converter, are mounted to an half inch acrylic panels. The panels are then mounted to aluminum rails that are attached to the bulkhead. The rails provide 1.5 inches of space for wiring. This means wiring can run behind, instead of around the large devices, which makes for easier and shorter wire runs.
Battery Charger panel. Note the hinge at the bottom and cutout to route wiring.

The acrylic panels are attached to the rails with bolts at four corners. The lower portion is split with a hinge enabling the upper bolts to be removed and the device to be "hinged down" for access to the back of the device and the wiring behind.

Same panel, hinged in the down position., providing access to wiring and bulkhead.