Another very productive week working on the hull of mv (motor vessel) Möbius here at GreeNaval Yachts.  Might not be the most visually exciting week but much progress none the less so let me walk you through the week with photos I’ve taken along the way.  And there’s the usual video summary at the end as well.

When we left off last week the longitudinal stringers were being laid out on top of the aft and foreward deck plates.

This is standing at the aft end of the aft deck which is where the swim step will eventually be and looking forward at what will be the floor of the SuperSalon main living space.

Keeping in mind that the hull is being built upside down this is the underside of the deck plates and so these stringers are running along what will be the ceiling of the boat when you are inside.  None of it will be visible on the finished boat of course as all the aluminium AL surfaces will be heavily insulated with EPDM rubber glued on all surfaces and around all the stringers and frames.

The stringers are tacked in place just to hold them in place for the next step,

which is placing the top of each transverse frame onto the decks by sliding their slots over each stringer.

Speaking of the frame tops, they have been piling up all week as the crew has been busy tacking the flat bars onto each top member of the frames.

You can see the slots I’m referring to quite clearly in these two shots.  They end with a hole to eliminate stresses when the stringers are welded in place and to provide a space for the welders to reach through.

The larger holes you see in this stack of frame tops are “lightening holes” to reduce weight and some also provide ready access for any conduit or plumbing runs that might be needed.  However all these plumbing and wiring runs have already been placed in the 3D model and are primarily located in the sides of the frames in dedicated openings in the frames.

They have also been welding up these T shape vertical running stiffeners which will soon be welded to the AL plates which form the bulkheads that we’ll see next.

This will give you a sense of scale of these stiffener T’s.  The edge under my thumb will be welded to the bulkhead plating and the small bits of aluminum you see between my thumb and forefinger are temporary braces to hold the T sections perfectly perpendicular to each other until they are fully welded once everything is in place.

Enver and Ugur are working on one of the bulkheads here and laying out the lines where the stiffeners will be tacked in place.  For some reason the CNC cutter failed to etch in some of the guide lines on the plate so they are marking these out with a straightedge and felt pen.

One detail to notice here is all the small rectangular holes you can see cut into the plate.  Each of the stiffeners have matching “tabs” cut into their ends which fit into these slots and guarantee that each stiffener is in just the right place.  Makes it quite quick and easy for them to connect the edges of these slots with a felt pen line which will ensure that the stiffeners stay in just the right spot as they tack them in place.

Here are several of the vertical stiffeners tacked onto one of the bulkheads.  The tabs and slots are under the ends of these stiffeners.

The slots along the top edges of this bulkhead will soon be filled with stringers when this frame is stood up on the deck in the jig.

Enver, our Master Welder, is tacking some of the simpler flat bar stiffeners to this intermediary bulkhead.

If you look closely at that little arch of aluminium plate you see in front of Enver, (click to enlarge any picture to full size) you will see that he has tacked it onto the AL plate and then fitted an angled wedge piece of AL between the inside top of the arch and the top edge of the stiffener.  You will see these being used hundreds if not thousands of time throughout the hull construction as this is how you pull two parts tight together before welding to make sure there is no gap.

And here is one of the water tight bulkheads with some straight flatbar stiffeners tacked in place.

That oval shaped hole at the bottom of the photo is one of those dedicated openings I mentioned earlier where plumpbing and wiring runs will pass through.  There will be an aluminum collar fitted through each of these holes for the pipes and wires to pass through and because this is a watertight bulkhead these will then be sealed tight with special pass through fittings.

Standing back a bit you can see two of the bulkheads with their stiffeners tacked in place.

When not helping out with the bulkhead assembly, Ugur is seen here carefully clamping the flat bar stiffeners to this upper frame piece prior to tacking them in place.

The large radius in the flat bar has been bent to shape in the hydraulic press using guide lines etched onto it by the CNC plasma cutter to show where the bend starts and stops.

One of the many frames with the stiffener flat bar tacked in place …..

………. and added to the the collection forming under the jig.

You will notice how the stiffeners are run long, going past the miter joints of these top members of the frame where their vertical pieces will be welded.  This ensures that no two welds line up with and increases the strength that much more.  Most of the frames and stiffeners are made of 10mm plate.

These pictures will also give you a better sense of just how massively strong this hull framework will be and is one of the many SWAN features that Christine and I already love about the design and build of Möbius.  SWAN = Sleep Well At Night

And that brings you up to date with our progress through April 11th, 2018.

Here’s a short video summary of the week that will give you an additional perspective on the week.

Thanks VERY much for joining us and don’t be shy about asking questions and suggestions by commenting below.