I have just completed my drawings of the PS Bunyip. They are only rough sketches and there was quite a bit of extrapolation involved.
Some of the dimensions proved very elusive, and in the end the height above waterline and draft had to be guessed and redrawn several times to get the proportions right. (Trial and Error - emphasis on the error)
I have only found two images of this ship so far, but I am fairly happy with the end result. I am going to begin work on the twin hulls shortly. The initial plan is to produce a static model with a solid hull, but I may attempt a working model depending on the results.
The scale is probably going to be 1:36 giving an overall length of the model of approx 35".
The completed drawings are 1:122. On 5mm ruled graph paper this gives me one 5mm square for every two feet.