01-17-2014, 11:53 PM
Quote:Still, is there any calculations how should be dimensions of 15 mina lithobolos ?Wow -- that's quite a monster you're attempting. 15 minas = a quarter talent; this is the equivalent of a Roman 20-pounder! By way of comparison, the ballista recently (fairly recently) constructed by Len Morgan and Alan Wilkins is a 2-pounder.
There's no easy answer to your query. You and your friend will need to work through Philon and Vitruvius, calculating the dimensions of each component. As you probably know, the size of the "module" (diameter of spring-hole) is calculated by multiplying 1.1 x cube root of (100 x weight in minas) = 1.1 x cube root of (100 x 15) = 1.1 x cube root of (1500) = 1.1 x 11.5 = 12.6 daktyls = 24.3cm. The springs are 9 "modules" in height, which is 218.5cm -- so your 2.2m springs are quite correct.
What other components are you having trouble with?
