Source: Yuri Pasholok’s blog Hello everyone, an interesting thing appeared on Yuri Pasholok’s blog. On the example of the IS-4, Yuri Pasholok demonstrates, how much can various projections differ from reality. He states that if someone claims some vehicle to be modelled after “factory drawings”, you don’t have to take that claim too seriously, because – if I understood what he wrote correctly, there is not only a significant difference between various book drawings and the final product, there is also a difference between the general factory drawings and the final product. Basically, production plans consist of series of detailed partial drawings, by which the vehicle parts are created. General drawings however (as in, general overview, even though created by the same factory) tend to be much less accurate (this is apparently the reason why for example Wargaming preferred the partial IS-3 turret plans to the general model in the recent IS-3 turret changes). Here is a comparison, made by Yuri Pasholok: The photograph above is of the serial IS-4 vehicle. Red lines belong to the drawing published by well-known Russian author Michael Svirin, blue lines represent the general drawing of the IS-4M (Drawing 701 – Sb.3 from April 1952). As you can see, both the general factory projection and Svirin’s projection (from the book) are different from reality. To compare, here is a comparison of a partial turret drawing from IS-4M (701-157-Sb.3) with the real life tank: As you can see, it fits much better than the general drawing, demonstrating the superior accuracy of partial drawings.

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