both the LBSC designs for Maisie and Juliet show the Cylinder mounting hole size as No. 21. I assume the hole size No. 21 in England is the same as here in the USA, that is 0.159". In neither of these drawing sets do I see the actual Screw size for the attaching Screws. The 0.159" seems rather coarse for 4BA. Would LBSC have expected someone to use a 5/32" Screw (I'm assuming that back then someone would have a 5/32"-32 Die or some such thread) ?
Hi Bruce, LBSC's notes says the cylinders are attached with 5/32" screws or bolts with the nuts inside the frame, for Juliet, I guess that Maisie would be the same.