Some very good bits spotting so far
CI: Chassis from Airfix tiger, GW treads. Main turret from Scharnhorst model ship, Secondary Enforcer Mk1 turrets (Mk2s would have been better, but weren't available when I built the model. Tall gothic windows are press moulds from E40k ruins. Small arcade of windows below main turret is rear part of an Imperator foot. Front relief is various plastic IG infantry filed down. Large statues from BFG Imperial Battleships. Large side windows are scratch built from plasticard, using that textured palstic tie that is sometimes used as packing material for larger cardboard boxes. throw in some FW brass etched Eagles and a lot of plasticard and that is pretty much it.
As for the Imperator, pretty much the same thing applies: Plenty of plasticard. There were an extensive guide with pictures before the forum meltdown a few years ago, but the short version is to use two pieces of plasticard. 1mm for the basic shape, and then you add a thin second layer (0.5 or thinner) for the individual armor plates. It is pretty simple once you get the hang of it. Only exception is the head which had to be sculpted from Green Stuff/Miliput. The 4 bastion turrets are shaved down Plastic Rhinos with Warlord Turbo Lasers added. Then just make sure to add plenty of gubbins from the bitz box all over so it looks nice and textured.
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