I have a OS FS - 30 for some time now. Wanted to build a 3D plane for it. Came across this hand drawn plan of Twist - 40 look alike from RCG.

https://www.rcgroups.com/forums/attachment.php?attachmentid=2455117

Plan is courtesy waldopepperaxe

https://www.rcgroups.com/forums/showpost.php?p=12003025&postcount=8721

The plan is huge bigger than a A0 size paper.

Got it printed scaled down on a A0 size paper. Wingspan is now 36" after the scaled down Print. Should be appropriate for the OS FS-30 which is a size 25 equivalent.

After the scaled down build planing to continue on the original size version too for a size 52.