hi ya there Nordlys
Nice model there. Was this your first scratch build? I have found many a time, when talking to newbys at scratch building, they tend to try and overthink the build before they have actually began to make it. Personally, when I first start to build a model, I work it in several stages - obviously I study the plans and I have in my head a rough outline of the model - where I would like to fit the motors, where I would like to fit the batteries - approx. how long the prop shaft should be and at this stage all of my thoughts are just theoretical and open to change at any time. It is just to give me a rough ballpark along with how I am going to build the hull, what methods and what materials. Also, like we have been discussing earlier on, accessibility into the model.
So, lets say I was going to build this particular model - this is how I would approach it now:
I have learnt through time to build a model on a building board, building the model upside down on there. This has several advantages which have been discussed in other postings. Mainly though, it keeps the model true from warping and also it keeps it safe and gives a steady platform on which to work. Then I would consider the materials to build the model from and in this case, I would want to keep the hull reasonably light and therefore I would be looking at a good quality 4mm 5ply thick plywood - something like a Birch ply (good quality from say Mantura Modelling)
I would then be thinking of the keel which would also be of 4mm thick ply the same as the frames. Either side of the plywood keel I would glue 4 x 4 Obechi square strip wood to strengthen the keel - this would be in between the frames. This also gives the planking something to lie on and glue to when you are planking the hull.
From the keel to the chine - I would say put 3 stringers of 4 x 4 mm Obechi strip from the chine to the deck I would put 2 stringers in - same again 4 x 4 Obechi strip. For the chine stringer and deck stringers I would laminate them from 2 pieces of 5 x 1.5 thick Obechi. This obviously when all glued and assembled would be sanded.
I would diagonally plank using 10 mm wide x 1 mm thick - again Obechi/similar wood.
At this stage it would be entirely up to yourself whether you want to double diagonally plank, using a mahogany strip veneer.
Or, you could - as I have done on my last model - use the finest of fine (and it was like silk woven cloth) This material is used in aircraft modelling to skim the wings and they say it isn't useful for model boats with it being that thin. This I covered with ZPoxy Resin.
Just food for thought and I hope it inspires you and gets you on with the build

John