I just read that the deadeyes should be 1/2 the diameter of the associated mast. I can get 5 or 6 mm deadeyes and my mast is 11mm. Do I choose bigger or smaller? I don't think making them is an option.
According to Haeckel, the deadeyes should be 1/2 of the mast diameter or a little bigger so 6mm makes more sense. But I guess 5mm won't be a crime ) If you have a chance to fit both of them and check which you like more. Maybe even make a couple of them from the cardboard to check.
I've read that when in doubt, go smaller if possible! But again, it's all about SCALE! Usually, smaller looks better to the eye, At least that's been my experience! Rick 1011
1 mm difference in size is only .5mm added to the width on each side - which is not much, but visually, could make or break. I am not sure, I think I would go with the smaller.
From what I've seen the dead eyes are sized bigger where they connect to the lower sections of mast with heavier rope.. They get smaller as the connetions to the mast go higher and the rope size gets smaller.. On any one set of back stays there would only be two or three sizes at the most.