While I spent this past week up in Amsterdam walking the miles of aisles of the HUGE METS 2018 Marine Equipment & Trades Show the rest of Team Möbius was hard at work getting the frames for the tank access ports welded to the tank tops and they also started work making the big hatch lid that seals off the access hatch into the Engine Room as well as the big hinges for the arch we showed you last week as well.  Let’s go take a look ……………….

IMG_20181116_095817You wouldn’t think that we would be happy to see all these big holes cut into all the tanks that had just been so carefully welded up and pressure tested to make sure they were all sealed tight.  But you’d be wrong!  I need to have a way to access the inside of all those many baffled sections within each of the 14 fuel and water tanks that create the lattice type grid of the below the waterline portion of the hull on Möbius and that is what these access ports are for.


In last week’s blog post you saw the two halves of these 25mm thick frames being welded and the rectangular holes being cut into the tank tops and now you can see how these frames are welded around the perimeter of all those tank top holes.  The series of small  holes you see around the surface of each frame are threaded for the 8mm SS bolts which will be used to clamp the 6mm thick lid plates down to the frames with special fuel safe gasket material in between to seal them tight. 

The inside dimension of these frames is about 250mm/10” square which gives plenty of room for me to reach in all the way to the bottom of the deepest part of the ends of each baffled tank compartment with something like a big vacuum hose if it were ever neccessary to remove any buildup of debris in any of these tanks over the years of use.

We go to great lengths to reduce the possibility of any contaminants entering our tanks.  The only source of fresh water to fill the water tanks is our high capacity water maker, never any water from shore side sources, so we know that it is always very pure and clean.  For the diesel fuel we have an Alfa Laval centrifuge that removes even the tiniest of particles as well as any water or other contaminants which might be in fuel we take onboard so we expect our tanks to stay extremely clean at all times.

These frames will now have all their edges and welds cleaned up and the lids and gaskets will be bolted down for the last pressure test to make sure all tanks are fully sealed.  Once that is done and they have been all pressure washed and cleaned the tanks will await their first fill up. 

Oh, and BTW, we are now accepting any and all contributions to the first fuel fill up!  I’ll let you do the math but the total volume of all our fuel tanks combined is over 14,500 liters/3825 US Gals.

Just sayin’ ……………………………………..


Several of you have asked about the water tanks I mentioned that were on either side of the engine and CPP gearbox beds and this shot inside the Engine Room will show more clearly how these tanks fit in here.  In addition to the fresh water they hold, these tanks also help add more mass to this area of the hull which will absorb some of the vibration and noise transfer and with our help ensure that Möbius is nice and quiet throughout when we are on passages and Mr. G is quietly powering us to our next destination.


Taking a look around while we are inside the hull, the stairs going up from the Master Cabin to the front of the SuperSalon have been fully welded and cleaned up.


Meanwhile, up on top of the foredeck the coaming we’ve been watching as it was assembled and tacked has also been fully welded and cleaned up.


The bottom edges of the big 30+ mm/1.2” thick panes of laminated window glass will run along the tops of this coaming and the sloped edges will help deflect any green water that comes over the bow in heavy seas and manages to make it this far back.


Diving down to the underwater areas at the aft end of the hull we see that the boys have been busy finishing up the welding and now smoothing out the surfaces of the prop shaft Skeg. 

Aluminium is just such a great material to work with and IMHO SOOOOOOOoooooo beautiful to look at as well.


This closer look at the Starboard side of the Skeg shows the finished welding around the prop tube and how the welds between that 25mm thick vertical keel bar and the 15mm Skeg skin has been ground and faired smooth.

Keep in mind that the outer hull surfaces which are below the waterline will all be painted, the only paint on the whole boat, because we need to have the anti fouling protection below the waterline.  This means that we can use epoxy filler to create perfectly smooth and well radiused fillets in all the corners and transition areas which enable us to have the just right surfaces for best hydrodynamic flow of the water especially in this critical area of water feeding into our slow turning 1m diameter CPP propeller.

As if that wasn’t enough, a super smooth bottom also turns Christine and me on.  No, no, NO!  Not that way, it is just that WE are usually the ones who have to dive in and do all the cleaning and scraping of any buildup on the hull surfaces and prop.  You learn over time just how much even the slightest bit of growth slows down the boat and reduces hull efficiency so we like to keep our bottoms very clean and smooth as a baby’s bum! Smile


So what’s new you ask?  How about this big hatch door that goes over that big opening in the aft deck above the Engine Room.  We will see this get finished up and fitted in the next few weeks but you can already see the general construction of the underside of this hatch door here.  The inner framing creates the open boxed profile perimeter that will protect the rubber seal that will line the bottom perimeter surface you see here and this seal will be pressed firmly against the top edge of the opposite facing frame around the perimeter of the hatch opening welded into the aft deck. 

When closed, this hatch door will sit flush with the aft deck level and be covered in the same non skid material as the rest of the deck so the whole aft deck area will be completely free and clear of any obstructions.  The door will have gas cylinders tucked into this perimeter area to assist in opening this door much like you’d have on the rear door of an SUV or hatchback car.  There will be a series of “dogs” or handles at intervals all around the inside edges so this door can be pulled tight against the rubber seals and make sure all the water stays where it belongs; OUTSIDE the boat!

Arch up   downThis quick rendering of the aft deck and SkyBridge areas helps to show where this Blue hatch door sits overtop the Engine Room below and within the two Red ER Vent Boxes.  The hatch is large enough to allow the whole Gardner and Nogva CPP gearbox assembly to be lifted into and out of the Engine Room.  It will also provide me lots of fresh air and sunlight anytime I need to be down in the Engine Room doing maintenance when we are at anchor.

If you didn’t catch last week’s post, the purple components in this render shows how the arch and bimini roof overtop the SkyBridge folds down to “Canal Cruise” mode.


Can you guess what these aluminium things sitting atop the other end of the hatch door are for?

Correct, these are the big hinges we first saw last week and you have just seen in the rendering above, that enable the arch to fold down 90 degrees to significantly reduce the “air draft” or bridge clearance, which is the height above the waterline for situations such as cruising through inland canals in some areas of the world where there are lower bridges. 

The regular air draft from the waterline to the top of the arch will be about 6.4m/21ft @ half load and then there will be radar and antennae above that so overall bridge deck clearance will be more like 7m/23’.  Usually this is plenty of room for most bridges in seaways but by folding the arch and SkyBridge bimini roof down our bridge clearance would drop down to a svelte 4m/13’ which will open up a tremendous opportunities to explore so many more parts of the world. 

As you are discovering, we call these boats eXtreme eXploration eXpedition Passage Makers or XPM for good reasons!

That wraps up the week that was November 12 to 16, 2018.  Another fabulous week of great progress for Team Möbius and my first experience with the giant METS boat show.  I will try to write up a separate post here with more about what I saw and learned at METS for those of you who might be interested in those details. 

Sorry but no video this week but I will do my best to make up for it next week.  If all goes as planned I will have some very exciting video to show you next week as it looks like we will start moving boats including Möbius over to their new home in the brand new Naval Yachts shipyard!  So stay tuned for more next week and as always be sure to add your questions and suggestions to the “Join the Discussion” box below.