If you are referring to the single, double and triple blocks, plus other blocks like dead eyes, I am sure there is a ratio of the dimensions of the individual blocks of that is what you are referring to. If so, then I do not know of the ratio used. It is obvious that a block for a ship of the line would be too large for a basic schooner. I would have to research this.
This is a chart. The rope sizes and blocks I believe are in real sizes. First if you have a real rope diameter of 16mm, then you will have to determine the final from ratio like 1/90 size ship. That would be .17mm diameter line. Therefore take the measures given and calculate accordingly. If the width for “B” is 160 for 16 size rope or .17mm then “B” would equal to about 1.8mm wide.
This particular post is going to be removed soon as i was copying a small portion from a book only for a brief time to allow for education. SOS has a policy of not copyrighting. However the snippet of info is strictly used for education and is not and was not meant for redistribution by anyone. Soon, this post shall be removed.