The Pz.Kpfw. IV Schmalturm was one of the stranger German paper panzers. It represents the final- and unfinished- attempt to upgrade the Ausf. J. version of the venerable panzer IV into a tank that was still capable of taking the ever-evolving enemy armor head-on. Schmalturm means narrow-turreted, and it refers to the Daimler-Benz developed turret upgrade for the Panther. It was designed to reduce the shot-trap under the mantlet, increase the armor protection without increasing the weight, reduce the frontal profile, incorporate a stereoscopic rangefinder, make it cheaper and faster to produce, and fit into the existing Panther turret ring (among other requirements). The gun was to be the 75mm L/70 gun, which was modified to fit into the smaller turret, and the muzzle break was removed.
This turret was destined for the Panther ausf. G version, which was to be called ausf. F. from then on, but the war ended before this vehicle could enter the production lines. A couple of prototype turrets were finished, but not completed; for example the Zeiss viewfinder was never fitted.
There were some plans to fit this turret onto the Panzer IV Ausf J chassis, making a “cheap”, or “value” version of the Panther ausf. F: same turret carrying the same gun on a much cheaper hull. There were never serious attempts to create a prototype. The Panzer IV hull obviously would have had to be modified to accommodate the larger diameter turret (widening the vehicle, and increasing its weight), and the suspension would have had to be seriously upgraded to actually be able to carry the increased weight of the hull and the turret. The firing of the gun would probably have stressed the chassis and the suspension over their limits, especially if the turret was not facing directly forward.
The reason why the construction of this vehicle was never seriously considered is simple. Even if the war had not ended in 1945, this version would never have worked. By the time the panzer IV’s evolution reached the Ausf. H version, the chassis was at the end of its capacity. The long 7.5cm KwK 40 gun, and the applied armor had already made the tank front-heavy; the front suspension was already under constant pressure. It was simply impossible to increase the tank’s weight even further. It does make an unique-looking panzer IV variant, though, so it’s worth building one.
The conversion set comes in the usual CMK blister pack which protects it against anything the postal services could reasonably throw at it. (Some resin parts were broken off from their casting blocks, though, but no parts suffered any damage.) It contains the typical, clear instructions, and the parts themselves.
The quality of the parts is very nice. The PE is thin and crisp, and very easy to work with. I could not find any bubbles or casting imperfections. There are some extra pieces provided, which are not strictly necessary for the conversion, but will enhance the model a bit. You get the spare road wheel holder as a PE part, and some hatch handles, for example. Strangely enough CMK provides the rear mudguard as extras, but not the front ones; so if you fancy display your model with damaged mudguards, you only will be able to do so on the rear ones.
The gun itself is provided as an aluminium turned barrel; this is much preferred to the resin gun barrels which might bend or sag (or break). The resin bits (road wheels, turret, two types of mufflers) are also very good quality; the subtle texturing on the armor plates of the turret looks especially great.
The construction is straightforward. The instructions are very simple and easy to follow; you merely have to swap the kit’s turret for the resin one, and change the side skirts. You’ll also have to make a decision which muffler you want to use. The turret needs three PE lifting hooks to be attached, then glue the gun in place, and you’re essentially done. (Since historical accuracy was not a real concern, I chose the camo pattern I like most from the MMO World of Tanks, where this vehicle serves as a premium tank.) A fast and easy conversion.
There are a couple of issues I’d like to mention, though –none of which are deal-breaking. (Disclaimer: most of these “issues” are not really issues, since we are talking about a “sketch-on-the back-of-a-napkin” paper panzer. There were no serious attempts to design it, let alone constructing at least a wooden mock-up, so there is no “historically correct” version of this vehicle.) One of the most glaring issues with the conversion is the base kit it is using. The suggested kit is Revell’s 1/72 Panzer IV ausf. H, which has some differences from the Ausf J model the actual vehicle would have been built on. The Ausf J was in many ways a “value” version of the Ausf H in itself; many components were simplified and omitted. It only had three return rollers on each side (these were already changed into metal ones from the rubber rimmed version midway the Ausf H production; yet the Revell kit seems to have rubber ones). The turret rotation was done manually, the side-skirts were changed into a wire mesh to save weight, the radiator housing was simplified, and the pistol ports were omitted from the turret. Some of these details (the turret, and the mesh) will obviously be corrected using the conversion set, but the radiator housing and the return rollers will need to be changed if you want to build an “accurate” Schmalturm. The best would be to use an Ausf J. base kit. (I could not find one.)
The conversion itself also has some issues. It does provide the mesh instead of the armored side-skirts; however, it uses the mounting brackets from the original kit, which are quite chunky in this scale (having been made of plastic). It would have been more fortunate if PE replacements were provided by CMK. As it stands, if you really want to make them look good, you’d have to get an aftermarket PE set for your aftermarket conversion. (Extratech produces side-skirts for the panzer IV; the brackets would be perfect for this kit.)
The road wheels that CMK supplies are nice, but their pattern is different from what I have seen on historical photos of the actual tanks. Since I’m not knowledgeable about the different types of road wheels the panzer IV was supplied with, I cannot comment on their historical accuracy. One thing stands out, though. In the schematics you can find online about the Schmalturm, the first two pairs seem to be steel rimmed. It was probably necessary to use them as the rubber rims would most likely disintegrate due to the stress of the increased weight of the already overburdened chassis. It would have been nice to receive these special wheels; otherwise I really can’t see a point in providing road wheels with the conversion set. (Other than the fact that now you are able to buy a panzer IV hydraulic chassis conversion, and have all the plastic leftovers from this conversion to build one.)
The other issue is the widening of the chassis. This vehicle –probably- would have required the widening of the panzer IV chassis to accommodate the wider turret ring of the panther’s turret. This would require a major surgery on the base kit –or a completely new resin chassis. Since the difference between the panzer IV and panther’s turret ring was 5cm (160cm vs 165cm), CMK opted to ignore this issue, and it’s probably for the best.
None of these issues are deal-breaking. The conversion set is good. It builds well, it’s simple, and it gives nice-looking results.