Planking details of Hans Klaar's Ontong Java?

I was looking at some old posts here and around the net about the building of Ontong Java and I'm struggling to make out the details of how the hull was constructed.

More specifically, how the planks were attached to one another.

At first it appeared to me that it was a sewn boat, although I found no images or mention of that specifically. I finally an image here...

Ontong Java II by Hans Klaar https://www.boatdesign.net/threads/ontong-java-ii-by-hans-klaar.42942/page-2

That shows some dowels between the planks.

I'm still puzzled though.

Are these wooden or metal dowels?

What cinches the planks together, or keeps them from parting. If anything other than the dowels and framing.

 

The simplest way would be just ask.

You could ask his friend J Caprani (has a gmail account jcaprani at gmail dot com), his email address in this forum if you look through previous ontong java threads. You could ask the owners of the original ontong java (now mareva), they have facebook, their wordpress site is here memoirs of missions, ventures, voyages, sojourns and other vagabondage https://frequenciesoflife.wordpress.com/ .

If worse comes to worse, I could provide Hans Klaar's email address, (privately) but would prefer you try two other approaches first.
My guess with 99 percent surety is that the builders used dowels. Nothing wrong with dowels, used a lot in building Indonesian boats. Not used as much in western boat building as the capital cost vs labour cost makes metal bolts the best choice,however when labour costs are less than five dollars a day, it is much cheaper to use more labour intensive materials that where the cost of the wood for a dowel might be five cents, whereas a stainless steel/ silicon bronze bolt might cost five dollars, 10 dollars or so.

 

Just a clarification. If you look a the time lapse building video it is apparent they are building the hull by first building the shell (the planks) and then adding and frames after the fact. Obviously you need a lot of skill and time to ensure the frames fit the inside of the hull tightly. I assume they measure, maybe make patterns on some material then transfer that to the timber itself and shape the timber using an adze. An adze is like an axe except the blade is at nighty degrees.

Looking at YouTube videos of building Indonesian wooden boats, (pininsi) they use many small wooden dowels that go through one plank and into the next. Half the dowel in one plank, the other half in the next plank. What I mean is that they drill holes into the thin edge of the timber, put dowels in them, then they have to put holes into the next plank , and slot the plank in. Not easy when a plank is only two inches wide or so, but that is the way they do it. Obviously when frames are added, they can then use larger dowels and go through the plank to secure it to the frame.

I would recommend checking out some Indonesian wooden boat building videos on YouTube, you can see them use this method, joining planks together via edge to edge doweling
alternatively you could find some fellow on facebook from 'The Gambia' pay his 10 dollars ( a weeks wage) to make a video on building boats there