Hi ya David
When we build models we have to take into consideration certain things. We cannot always scale down things from the real boat to the model exactly. Same way as we will never be able to scale down the sea we sail in and the wind to the same scale as our models. Although in your original boat they will have used pitch pine and oak for the frames, the material of the timber, the oils and grain in the timber wouldn't really be a problem in the real boat. When we build a model - we cannot always use the same materials. A while ago I built a double diagonally planked hull - and I wanted to replicate the canvas and white lead paint that is used between the layers of planking, couldnt really use calico canvas and white lead paint as in the original hulls - so I reverted to using an aircraft tissue paper and pva glue. I know anyone will ever see it, until the hull is broken up - but when I tell people at the lakeside its a talking point.
The other thing to remember is 50 years ago, when these boats were first built the paints and varnishes had a lot of lead in them and noxious chemicals to help them adhere to the timbers. Now they dont have lead / harmful chemicals in the paint - also for underwater protection they used to use what is known as red lead. You never see a vessel painted with that nowadays.
But, when we build our models we replicate this red lead with non toxic paints etc.
The problem you have with using pitch pine is the grain, as well as the oils in it. You may have to even steam/dampen the planks you are using to bend round the shape of the hull. Once the heat hits the planks, it will encourage the sap and oils to rise to the surface once again.
What I strongly suggest before you assemble the model is to get some scrap bits of wood of the same material and dimensions as your planks - try gluing, varnishing, painting them and see what happens. If this is successful, then proceed - doing it this way saves (believe me) heart ache of getting half way through a hull and watching it disintegrate in front of your eyes.