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hello andrej i hope you made it over here - please post something
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Ok, landed here no problem 
My next question would be about dimensions of cell ‘beams’. For example, for the largest cell which is a roughly prism-shape of around 30x40x40 cm, what should be the adequate width of a connecting beam? 5 cm, more or less?
Of course, it would be useful to have some estimates on the thickness too… You mentioned it can go down to 4 mm. I can see that getting it thin may be advantageous, it can always be strengthened later by spreading more concrete if it becomes unstable or wobbly, right?
I would start with a form element that allows building 3-5 cm beams for convenience as this is what you get naturally by the spoon dots .
After deforming i would come back and thicken the beam with a second layer and then repititive layers to get something of maybe up to 5x5 cm (for the mayor beams) as this is the size where a concrete part has a general strength where you can step on it without destroying it.
Instead of forming a solid 5x5 beam you might be better off forming a T beam h with 1cm layers
The thinnest parts of the skeleton might be in the same category as you see in a brick.
When you step on a brick you are not concerned of breaking it.
The general idea is that you get a skeleton strong enough so you can use it to climb around on it
without destroying it.
This facilitates the process of tensioning fabric over it and then streching it a lot.
Also you want the truss elements strong enough to drill in it and screw pieces of plywood on it when you pack the mass concrete in.
Our 4mm wall thickness piece in Cartagena was a “study how low can you go on the extreme end” so i would not go there as default - although it is possible.
The rock builders work with a concrete cover of 3/4 inch about 18 mm - that is fine to step on without a underlaying rib structure - so half of that is enough for a tough outer skin.
So, the idea is a thin paste of mortar to stick to a surface and then build up the thickness with regular concrete, coarse aggregate and all?
Building up a structure of concrete incrementally as you describe - spoon by spoon - would be highly advantageous, but what bugs me now is how are the problems in bonding so many new to the old layers solved?
Literature states that new concrete or mortar will not naturally bond to the old layer when set, and even delays in pouring can lead to problems like ‘cold joint’. To join concrete bonding agents and glue such as epoxy are recommended (but does that reach the strength of concrete poured at once?) So, how do we deal with that, is the point in using a glue and fiber in the mixture and would it reflect on properties of a vessel like submarine?
As I learned the weak interlayer strength is also the main reason why 3D concrete printing hasn’t caught up yet. I imagine that compression might mitigate lesser tensile properties to some extent…
No - it is more about having a suitable paste that allows to put a spoon dot of some 5x3 cm and then create a centimeter of the beam in every round. Where you can work fresh in fresh with the old dot just hardened enough to carry the weight of the new one. This way a weakening layer
will not form - the construction industry uses “slipforming” to create “cold joint free” pieces.
In cases where slipforming or working fresh in fresh is not feasible the default way to do things
is to let the fiber component stick out so it connects the old and new layer - this is why you see the rebar sticking out so frequently in concrete construction - it is to bridge the bonding weakness.
When this column is continued later the rebar will bridge the tension forces trough the cold joint
To come apart in the cold joint the rebar needs to snap.
So in theory the column would be better "avoiding cold joints " but how would you do 10 floors in one pour - or with a slip form - it would not be practical. Therfore in real world construction you see cold joints just EVERYWHERE and they are never fountains of problems of any kind.
In your paste you have paper fiber sticking out in a similar way - so the cold joint issue is not
really a big issue as the fiber is bridging it. (you will find it almost impossible in practice to seperate a piece on the cold joint - test it)
If you still have doubts just work a few wires in as if it where rebar
I am not sure if the statement that 3 D printing is not taking off - is certain…
But having a person spoon printing is many times more flexible than a machine will ever be…you can see and understand where strength is needed and specific dots have to go to reach the goal of a thin and elegant piece with just the right strenght.
It is more a “craftsmanship” than a “building sistem” or a coding instruction.
It will take some time until robots become good craftsmen that can build stuff to a required strength on their own flexible criteria.
It is most of all a matter of doing it - testing it - get an idea what works and what not.
A lot of stuff is written to get an article in a construction magazin or what not - and it is not very relevant in practical terms…
Other things are paramount - like the workability of the paste - and get hardly ever mentioned in the literature, because when you work on mixtruck scale, pouring tons of material in plywood forms, it does not matter a lot.
For me the killer is the drying out of the fresh material too quickly that happens if you work very thin… (and then spoil the required week long moister treatment)… it can reduce the strength to almost nothing…while a cold joint may reduce the strength only a little bit…so i recommend to focus more on moisture issues than on cold jointing issues …
The important force on a submarine hull is the compression force and cold jointing has cero influence on compression - only on tension…
Yes, I think I have better understanding of this now. Some things are still a bit unclear to me however…
As you point out, cold joints might not be a critical issue when it comes to compression, especially if connecting fiber or wire is used, but it would still be preferable to avoid them to the extent that it is possible. Slip forming accomplishes that by continually raising formwork and pouring new concrete at a certain rate. The idea is to make concrete always ‘fresh’ at the edges where it is growing.
So what I imagine this would translate to in cell construction is -
- Spread a spoonful of mortar over a form covered with plastic,
- Add another layer just before initial setting time so that it is fresh where it needs to grow
- Shape a curve in the still plastic mix (perhaps by removing some material by knife, using a template)
- Repeat the process until the thickness is reached and the innermost layers have hardened enough for the form to be removed
- Start forming another beam
(Of course, this would inolve many beams growing in parallel)
Is this correct?
If so, then I think the main issue would be how to keep up the continuous work. If the initial setting time is, for example 30 -40 minutes depending on the climate, it would be impossible for a single person to do unless he never sleeps…
I see you are still very much sticking to the thought to construct “cells”
You might think of a 12 m x 3m hull rather as something that is done in one piece from the keel up line by line just like a image is created in the printer line by line.
If the hull has 300 cm hight and you want to build it in 30 days the corresponding progress per day is only 10 cm per day
So roughly a spoon of material on any beam and hull part that is part of the line you are printing today.
As you do only 1cm the possibility that material starts to flow away is null.
In practice you may want to start a floating building site with a wooden plank that is on the bottom of your keel and allows you to place the first dots.
Instead of putting the wood on the water directly put it on a plastic sheet that you spread out on the watersurface and put the wood on it.
Wrap the borders of the plastic up so you have a dry workplace and you can cover the fresh concrete with the overlap of plastic to facilitate a moist harden out process.
After a week you should be 70 cm high with the keel section - means you should have a 12m long “canoe” that has a similar freeboard height like other boats.
At this phase you should be able to step on it and have tools and materials in the inside of your build.
Do a plastic roof over it as heavy rainfall still could fill it with water and sink it ( like any open boat).
You might find that a 12m boat is a bit small to have a comfortable building site inside of it - so you might want to change your paradigm here and think it through that it might be cheaper to build the boat to double that size…
Especially as you see now that the difference in cost of one bucket of material or 3 buckets is not as big in concrete as it would be in resin.
You would plan a workday as 10 rounds (a bit less than an hour per round) where you place a dot on everything that is on the level you are working.
When done with the round the starting point has hardened enough to recive another dot and so on…
I hope you envision that now different than “building cells and beams” it is rather “printing up a basket”… keel to top.
For me it was a good exercise to get a plastic baby bathtube and trying that process in a model.
It might sound somewhat weired on paper - but as soon as you start doing it you get a good glimpse how this can work on a big scale - and how you would set up such a building site.
As somebody who lives in croatia and is therefore familiar with yachting you probably know already that sailing a small yacht is not necessaryly easier than sailing a big one…
Here is Don Arturo with two spoons printing up a box that easyly could be the keel of a submarine yacht…
It is one of my early concept tests … back in 2008
Note the galvanized wires sticking out of the wall…
The front wall of the box is high to deal with the swell of boats passing by, but the stern part is kept low to allow a easy enter into the box - in a keel you would keep the divisions low enough so you can step over it… that facilitates logistics very much.
This specific piece was printed without the plastic sheet ( which is an idea that came up later ) we found that a filtration is no reason for panic - you can simply stop it with cement paste and baking soda for fast hardening.
If the leak is big and sudden - stop it with plastelin - there is virtually no thing that can happen in the process that would create a big problem…anything can be solved easyly…as soon as you reach a certain level of craftsmanship in this…
Termite-Tech™ means you can build literally anything and in any shape this way…on the water without a land based shipyard.
Thanks for more info… I do think I am getting there - the curved shape is formed one increment / spoon at the time. Seems quite literally ‘printing by hand’!
I have more questions on the details, of course, but first I need to notify you that this month I won’t be able to keep it up.
I am on a trip (Pula) and there have been some extra expenses, so I ll have to save up a bit before we can continue.
Meanwhile Ill see if i can catch a break and try a small scale exercise as you suggest…
ok have a nice trip … 
Hi Will,
Just to tell you that I am not back yet. In a few days I’ll be in Zagreb ready to work on my PC, so we can proceed.
I am not sure if there will be more than $50 this month, however. Perhaps we can discuss one one or two questions, and then go on we established the next month, what do you think?
Hello Andrej
Great to hear from you / the $50 month is ok for me.
I was thinking that we might offer a “managed floating building site in croatia” for people who want to invest in a submarine yacht.
The russian yacht owners whose mega yacht business headquarters was seized by “authorities” must all be lookig for better ways to live and work on the ocean while running their global business empires interference free.
The captain nemo lifestyle does this to a degree that a surface yacht does not yet offer.
So some of those people might be on a point where they are “ready to go and wire the money” if only somebody would offer a floating building site “somewhere in the mediterranean”.
The usual shipyards where megayachts are built are all “succeptible to seizure” as we have seen.
So we might be on the right spot in time with the right offer and just need to implement it.
Croatia and its coastline, might be just the right place, and internet might be just the right medium, to communicate that offer to the right people who are “ready for it” and want to “go galt” and implement “oceanic freedom” seriously.
Your private submarine might easyly take shape as a little side project, embedded in a bigger floating building project, that you oversee as site manager.
It might be fueled by funds that you earn as salary for running the site.
You might live in a floating home on the building site - with no land property involved into the project at all.
let me hear your thoughts…
Kindest Regards
Wilfried Ellmer
It is a great idea for an enterprise. I am thinking about it.
For now, learning techniques to build a submarine for my project is still a priority. I am not there yet as far as resources/ autonomy / personal situatiom is concerned, and going into a commercial business seems a bit more remote. (Not in a relatively near future, such as within a year or two)
However, i’d be interested to hear more about the concept and what it would take to realize it.
If someone were willing to be a pioneer investor like you imagine, and the money would cover the entire logistics, that would expedite things, of course. Yet there is the issue of whether they would pay someone with zero experience to do it. Perhaps not. Acquiring some skill first in a personal project might make sense, having something to show that I have been properly taught. I would also like to have a clearer image of legal issues we might encounter, such as related to an unregistered income, taxes, etc. My fear is that Croatia isn’t such a safe haven as it might appear…
Andrej,
For now the only thing required is your ok to explore such a project.
Because if you would not do it in case the opportunity arises - it makes little sense to offer the options to potential owners.
If you have age 18 ( how old are you ? ) anything needed seems to be ok.
Your english is good, your domain of internet also, your residence in croatia .
The financial autonomy and framework has to come from the project itself - that is kind of self evident.
It can not be asked from you to provide any kind of infrastructure or financial ramp up.
The skill set would come from me with the claim … have been there … have done that… will mentoring the build.
That is the baseline.
So if we agree on that baseline so far,
lets talk legal issues…
Sure, I agree. I would like to explore this further. If this is indeed viable and something unpredictable doesn’t come to stop me in my tracks, I don’t see why not do it.
My age is still very young, (38y) my health is so-so, there have been surgeries and and dealing with a myriad of chronic issues, but generally I feel fit and capable of light to medium-heavy labor. I have rarely been on a boat (or owned anything larger than a kayak) but I don’t have sea-sickness or something along those lines and tolerate the climate well. Living afloat /seasteading is what I am set to do anyway, so why not do it sooner and be paid… Of course, one thing is that I can’t risk to work somewhere so remote that I can’t do my check-ups or reach medical aid within few days at least if something comes up, I need to be mindful of that… Well, that about sums up my condition.
Ok, step one would be to to float the offer out on the internet and see what kind of response we get.
The possibility of something undpredictable is always on the table.
Therefore i suggest to structure the project in steps, and tokenize it.
The step 1 token would be “getting a permit with a permit number”
My primary thought would be to get an old fishing boat that already has a number and do a " refurbish project " with a possible “permit adaption” when the project starts to grow.
In this first phase it would be about “establishing a building site on the anchor place” and do some " internal build out " as many boat owners do… while living on the boat…
The key would be to keep the " disturbance factor low " for the neighbors - the more a secluded carst bay you can get - the better.
A possible setup how such a thing could look like is in the picture above…
It is obvious that this kind of floating building is even done inside of yacht marinas on many places - so getting a permit should not be terribly complicated.
After closing everything with vinyl over a frame of construction staging elements, you would just rip out anything from the boat, make a nice living space where you can live in comfort during the construction in standard drywall over the empty hull and then take it from there...
The token whitepaper would say : establish a floating building site on base of an old fishing boat close the site with vinyl and establish a office and living quarters.
During that phase you recieve your agreed amount of tokens over paypal every month and report how those tokens convert into a building site with text and pictures to the customer.
If phase 1 comes to a good end phase 2 is on the table.
Doses that look feasible to you so far ?
The practical part should be simple enough.
I have done a brief check of the law and couldn’t find anything on adaptation permit… Modifications that significantly change displacement or type of engine are the only ones mentioned.
As I understand, this step would involve basically raising a ‘tent’ on top of a boat to serve as living /working space. It doesn’t look like it should invite problems, but I’ll look further, perhaps ask on some forums.
What do you think should be the minimal size of the vessel? I would like to estimate the cost. I am also wondering how small one can start.