KV-1 and KV-2 Hull Undersides

Dmitry Volf contacted me a couple weeks ago and alerted me to an article by Oleg Rozhkov published on the dishmodels.ru site.  The article deals with differences in the hull underside details of the KV-1 and KV-2 hulls, and can be found here.

In KV - Technical History and Variants, Figure 7 on page 38 purportes to show the hull underside from the Model 1939 to the KV-1S.  This is in fact incorrect.  Figure 7 depicts the underside of a KV-1 or KV-1S hull manufactured by ChKZ from October/November 1941 onwards.  Earlier hulls however, differed in their details.

Hulls manufactured by LKZ up to July/August 1941 featured extensive use of rivets in the lower hull construction, as shown in the drawing below.  The front of the vehicle faces left in the drawing.

The joints between the plates were reinforced with rivets, and the torsion bar mounts featured six rivets.

Hulls manufactured by ChTZ from January 1941 until October/November 1941 were simplified in order to speed up production, as shown in the drawing below.  Again, the front of the vehicle faces left in the drawing.

The riveted joints between the plates were eliminated in favor of welding and the number of rivets on the torsion bar mounts was reduced to four.

When the LKZ production facility was re-established in Chelyabinsk in the fall of 1941, the hull underside was further simplified as shown in Figure 7 on page 38 of KV - Technical History and Variants.