never said it was - but i see what you want to point out.
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illustrations for education, teaching, distance learning, private study and/or research
personally i would start with these: Die deutschen Panzerkampfwagen III und IV mit ihren Abarten is actually two books in a series of many others* which are highly revised and published by motorbuch verlag stuttgart.
original title:
Die deutschen Panzerkampfwagen III und IV mit ihren Abarten 1935 - 1945, 1. Januar 1968
and
Der Panzerkampfwagen 4 und seine Abarten Spielberger, Walter Motorbuch, 1975
both books were highly revised unto 2010 and 2013 and have been re-published in several editions over the decades with a lot of additions.
another german book mentions as sources- for example: “bundesarchiv, tamiya (color drawings), bildband 11. pz.div., archiv scheibert, archive podzun-pallas verlag, zeitschrift […]”
there is mention of a pz3 schachtellaufwerk complete tank having been built, too, but no information about pz3/pz4 einheit can be found - or it could be exactly this one or one that is related to this project.
it seems tamiya often adds a lot of historical information along with their products. they probably have some kind of history division that would have done research into the variants and how they looked.
the latest editions can be acquired from amazon or motorbuch verlag, for example:
there should be many many other books that will have references on the models talked about here.
what i find funny - as a german - is that they refer to the (other) variants as “abarten”. in german its like saying: “omg, no! what are you doing?! you cant do this! you cant make a tank like that!” actually you would have to say: “pz3 or pz4 und seine / ihre ausführungen” - or sth
and its so true for this topic because the pz3, pz4 chassis makes you come up with a lot of insane ideas / ausführungen on what to possibly mount on top of it, because the design is so capable in itself. the word ausführungen really describes the mental thinking process that went into the shaping of the differences and thereby namegiving.
they couldve simply come up with an enlarged version of the pz3: bigger size, bigger armor, bigger gun but same shape - similar to the kv-1 and i find the kv-1 hull and pz3 hull very similar; if you look at the the rear and the front they look very similar in style - or - come up with a tank / armor design like stug or hetzer but with rotateable turret because apparently it was a huge issue if you needed to turn the gun with a fixed turret: increased wearout on mechanical parts, tracks need to be turned by engine, gun traverse is very limited with stug, pak, jagd, etc.
simple, big 1-lined wheels like hetzer, panther has that would give similar protection like t-34 wheels could also be very beneficial to such a tank on paper to provide additional protection; schachtellaufwerk seems way too complex and expensive. sure its good to have but hard to keep up.
the best design vision of “pz4.5” to me seems daimler benz vk3002 (db) because its just perfect in all aspects: diesel, aligned sloped armor, excellent weaponry, design and overall protection in all directions. it would be interesting to know if there are any similarities between the pz4 k, pz3/4 einheit, mehrzweck, 9/bw and vk db or if there was any interfacing and cross influencing in their respective r&d.
illustrations for education, teaching, distance learning, private study and/or research