After the novella that I turned last week’s post into I will change the pace for this week and write about something else I get asked about a lot and that more people can likely relate to than last week’s Tech Talk deep dive into fuel maps and CPP props.  And a lot shorter!

Hope you enjoy and let me know in your comments either way.

Green Grass Prototyping

In one of my former lives I was a drafting and CAD teacher and in the architecture classes I taught I showed my students the value of what I referred to as the “Green Grass” approach to prototyping.

UBC pano shot from their website  I took this title from a practice that I had first run into when I was attending the University of British Columbia in Vancouver and they were doing some major construction projects on this hugely awesome 400 hectares/1000 acres campus. 
When it came time to put in the many sidewalks and pathways around the campus rather than do the typical set of engineering studies to determine minimum walking distances, foot traffic density and the like, they instead just planted all these areas in grass for the first year. 
After being used that first year they went back and simply put in sidewalks and walkways on top of all the well trodden pathways had been made by all the people walking on them for the past year.  I thought this was a brilliant method that I admired for its humbleness of seeing that the users were the true experts and that “we is smarter than me” type of approach.  I have gone on to use this approach for the rest of my life and applied it conceptually to most of my many “build” projects over the past 50 years, the latest of which is the design and building of our new boat Möbius.  Hence this week’s title.
PXL_20210925_090841230Seemed all quite apropos that I should come across this perfect example on my walk to the bank yesterday in the small town of Finike Turkey where we are currently docked and working on Möbius at the Setur Finike Marina.

Pretty clear proof that the civil engineers who did this recent renovation miscalculated and forgot to put in this section of walkway that more people than me thought should be there!
I find this Green Grass Prototyping to be one of those concepts that is so simple and easy to understand, yet ever so smart and powerful.  I thought it was worth writing about both because I get a lot of related questions about some of the ways we have used this on Möbius and I also hope that it is a concept than many of you will find useful and powerful in some of your own projects.  Here are a few examples we have right now on Möbius.

Shading & Cooling of Super Salon

360 degree glass of Pilot HouseAfter living aboard for over seven months now, we are eXtremely pleased with the 360 degree views we have through the 26mm/1” thick glass that surrounds the SuperSalon or Pilot House.  It is a thrilling place to be both day and night.
Port side shot Mobius at dockWe knew that all this glass would require some additional attention to control the heat coming in from the sun as well as the heat going out at night and we have quite a few options as to how to control both of these.  As with most parts of boat design it is all about juggling the various pros and cons of each option and deciding which one will be the just right, just for us, Goldilocks choice. 
In many cases this is exacerbated by the fact that in order to evaluate many options you need to live with it for awhile and experiment with different arrangements before you will know how each possible solution works and how well it does or does not fit you.  For controlling the PH windows we have options that include applying some of the amazing new films that are being made, using blinds on the inside or using shade cloth on the outside. 
PXL_20210926_072834223This is where the Green Grass prototyping really shines and so we have been applying it to the shading of the SuperSalon glass.  For the past few months we have had this nylon mesh garden shade material draped around the sides and front of the SuperSalon.
PXL_20210926_124332857We bought a 20m length of 2m wide shade cloth that is readily available from home improvement and hardware stores as it is used extensively for everything from shaded overhangs on cafes to semi-privacy screening on link fencing.

PXL_20210926_124320260 And I used some of these plastic spring clamps in my Workshop to clamp the unused width of the cloth to the AL pipe handrails running all around the roof overhang.

PXL_20210926_124251200.MPThis has been working really well as it allows us to lift it up out of the way entirely in a few seconds and so we can experiment with how much of a difference it makes in the morning vs afternoon sun, etc..
PXL_20210926_072850258One of the unexpected things we’ve learned is that in addition to reducing the amount of UV and sunlight getting through the glass, this draped material keeps the glass itself much cooler and also forms a bit of an air insulation pocket in the large space between the cloth and the window glass.  Being loose and not attached at the bottom seems to also help in that there is a natural breeze blowing through this space keeping it from trapping hot air inside.
PXL_20210926_124357103It looks completely blacked out from the outside but when you are inside there is still reasonably good visibility so you know what is going on around you.
Still early in our prototyping phase with this but our current thinking is that we will still likely go ahead and put in some film on the outer surfaces that will reduce the UV and heat transfer without adding much tint or colorization.  But we think we will also do a more finished installation of this shade cloth by putting in some tracks or fasteners around the top and bottom and sewing up a strip of the shade cloth to attach to these.  Right now we are enjoying the HUGE difference this has made to the inside temperatures in the hot up to 40C/105F we’ve had this summer.

SkyBridge Furniture

PXL_20210926_073000610Another place where we have been applying the Green Grass approach is with the furniture in the large area up in the SkyBridge.  We purposely left his large area open and then Christine found some inexpensive patio furniture that fit just right into the dimensions of this area.
PXL_20210926_072951298It is all loose and easily moved about so we are trying out different configurations of these furniture pieces for a month or so at a time while we enjoy it each breakfast and evening sundowner’s.  We pay attention and talk about what we like, what’s working, what’s not with each configuration and I will use these when it comes time to build in a more permanent solution.
A good example of where this prototyping really pays off is that I’ve realized that the AL frame running around the circumference of the windows where they transition from fixed tinted glass to removable panes of clear acrylic, ends up being at the same height as our eyes when we are sitting down.  This gets in the way as you are looking out and showed us that we will want to install a raised platform for this area where the furniture will sit.  This will also make it easy for me to convert the table to a pedestal style that can be raised and lowered and will give us some easy to access storage under the platform.  I will build a prototype of this platform as well using PVC pipe and fittings for a framework and some plywood for the raised floor so we can Green Grass the platform as well and figure out the best shape and height.

Media Filter v2.0

split sand filter housingI’ve also been doing some Green Grass prototyping with the media or sand filter that does the bulk of the work filtering the sea water being pumped into our Delfin 250L/hr watermaker.

Apparently my first attempt with this plastic tank pool filter wasn’t quite up to the job as the 45PSI feed pump pressure proved too much for the seam and it split.
PXL_20210921_120837303So I found a more robust model that I could get shipped in here which is no easy task let me assure you, and spent 2 days getting this bad boy installed.  As you can see it is wrapped in glass fibre to withstand much higher pressures.
PXL_20210826_075713369Unfortunately the only size that would fit moved the six position valve (black plastic bit on top of the white watermaker) from the top to the side so it took me a bit longer to figure out how best to re-route all the hoses and get everything to fit.
PXL_20210922_124730364It was close but I ended up being able to get it to fit just nicely behind the Blue filter body and still allow me to see the various pressure gauges I have on the plumbing and to fit all the hoses coming in and out.
PXL_20210922_124753355The low pressure (45 PSI) Feed Pump first pushes the sea water from the sea chest through the Blue media filter which removes almost all of the algae, dirt, etc. and then it goes through the 25 micron filter on the Right here before going through the final 5 micron filter.
PXL_20210922_124813218All in all it worked out very well.  These media filters are not commonly found in marine Watermakers but they really do dramatically reduce the amount of filter cleaning and maintenance.  Without one of these I would typically need to clean each of the 5 & 25 micron filters before each use and replace them about once a month.  In my previous boat, adding a media filter reduced this to changing these two filters about once a year and even then they were still very clean.
layers of sand in medial filterInside the big Blue filter body, I first fill the bottom 10cm/4” (similar to the “Grade 2” in this illustration) with crushed rock about 20mm / 3/4” in size
Media filter cut awayThese rocks cover the spokes or laterals in the bottom of the filter and prevent the mesh surfaces from clogging with the sand above.
Media filter flow diagramSuper simple in operation, no moving parts, the water enters at the top and the water pressure pushes the seawater through the full height of the sand and then exits out the bottom outlet.
Zeolite in handRather than typical pool sand, I use what is called Zeolite which is far superior to regular pool filter sand in that it traps MUCH more and much finer particles and it cleans out much easier when back flushed.  From what I read Zeolite is a natural mineral formed millions of years ago in volcanic ash flows that settled in seas and lakes.
Zeolite structureZeolite a filtration area of about 1,000 times greater than sand media beds and the key to the truly amazing performance of this all natural Zeolite is in its molecular structure which looks like this.  Much more surface area to trap finer particles in much higher volume than grains of sand.
PXL_20210922_124736151After each run of the watermaker it takes me about 3 minutes to backflush the media filter with fresh seawater by simply moving the handle on the filter valve to “Backwash” and then about 30 seconds at “Rinse” and it is all clean and ready for the next run.

The mechanical pressure gauges and Maretron pressure sensors make it easy for me to monitor any clogging of any of the filters and know which one is clogged.

I could argue that fresh water is ultimately even more critical than diesel fuel for us in order to live the completely self sufficient and eXtremely remote life style we do, so having these extra layers of filtration and dramatically lowered maintenance tick of all four of our SCEM priorities of Safety Comfort Efficiency and Maintainability. 

Self Sufficient Freedom

Lau floating islands This is especially relevant when we are at the very tiny remote islands we so enjoy which often have very limited fresh water for themselves.  This is one of many favorite such spots we’ve been to, here in the Lau Group of islands in Fiji with a total of about 120 residents ashore when we were there in 2015.
Aur atoll MarshallsIn several instances in our past experiences our watermaker proved to be quite the relationship builder wherein we were able to add value to the lives of those ashore by providing them with more fresh water rather than showing up wanting to take it from them to fill up depleted fresh water tanks onboard.  This is the Aur atoll in the Marshall Islands when I was there in 2012.

Having a watermaker is also a key factor in our #1 benefit of this lifestyle which is Freedom.  Without a watermaker, passage making boats often have their schedules dictated by the range of the supplies they carry.  This applies to electricity needing to recharge batteries with shore power, diesel fuel when your tanks are too small to allow greater range and to fresh water as I’ve outlined above. 

Mobius @ 9.2 ktsBeing able to make all the electricity and water we need and having enough fuel that we only need to fill up about every 18 months allows us to travel the world with an eXtremely clean and minimal wake of disruption of the world around us. 

It means that when we reach our next destination we have no demands often constrained shoreside resources and no stress from desperately seeking more water, fuel or electrical power. 

Freedom indeed!

Thanks for joining me again this week, hope it was enjoyable and you learned something.  Please add your comments, what you learned, what you are still curious about, in the “Join the Discussion” box below.