Monday, 30 January 2017

Flames of War: The Polish 10TP Cruiser Tank.

OK so I managed to finish off my Polish 10TP Cruiser Tank a little faster than expected... and I have to say, Im spitting out canary feathers with this one. If I can get my head around how to cast vehicles properly I believe I may have a winner here.

Now, being a lazy inveterate, and the fact that my skills and understanding of how to do sculpting do not yet advance to the point where I can do tracks and wheels I have of course nabbed a few pieces from another manufacturer to see this over the line BUT it is my intention to one day backtrack and sculpt my own track sections for this sleek beast of a Polish war machine!

The History

The 10TP was a prewar Polish cruiser tank that never left the prototype stage. It immediately led to the development of the 14TP tank design although neither made it to full production due to the Nazi invasion of 1939.

At the end of the '20's the Polish Armed Forces declared that they needed a new tank design so they sent Captain Rucinski to the USA to try to buy a license for the Walter Christie M28 tank blueprints and production license. He was unsuccessful!

Owing to the failure of this attempt the Military Institute of Research Engineering (WIBI) Tank Design Bureau was set to design their own project based on the Christie model. The project was based on available data, leaflets and pamphlets, notes secured by Rucinski when he visited Christie as well as sketches that he had made. The project was all but ready by the end of 1932 but then work slowed to a crawl as the Tank Design Bureau became mired with upgrading the imported British Vickers E tank into the Polish 7TP design.

At the end of 1935 WIBI was liquidated and most of the records of the work done on the 10TP project was destroyed with only a few notes and sketches remaining. The remit for this work was taken over by the newly established Design and Testing Centre of Armoured Forces which reported directly to Armoured Forces Command. 

On 10th March 1935 design work was once again began on the 10TP tank. Major Rudolf Gundlach (famous for his reversible armoured vehicle periscopes) headed a design team consisting, amongst others engineers such as Jan Lapuszewski, Stefan Oldakowski, Mieczyslaw Staszewski, Kazimierz Hejnowicz and a Process Engineer called Jerzy Napiorkowski.

Although the tank prototype was still incomplete in 1936 it was included in the upgrade programme of Armoured Forces projected for 1936-1942. This programme was approved and supported by the Armaments and Equipmente Committee in January 1936. The 10TP was scheduled to provide the armoured battalions for four projected Motorised Brigades.

Supervised by Captain Kazimierz Gruner the first prototype was assembled in the Experimental Workshop of the State Engineering Plant in Ursus, Warsaw. Concurrently two Motorised Brigades were established with the intention of ultimately equipping them with the 10TP.

Assembly was complete by July 1938, delays having occurred due to the necessity of importing elements that were required in the construction, like the engine for example. It rolled out of the Experimental Workshop on 16th August 1938 to begin its road trials.

Driven by an experienced military specialist; Sergeant Polinarek, under the personal supervision of the Chief of the Trial and Experiment Department in the Bureau of Technical Studies of Armoured Weapons; Captain Leon Czekalski. The initial trials were kept secret because of the activities of the German Abwehr and Fifth Columnists which were just starting to ramp up their activities before the breakout of war.

Other than stoppages due to minor faults the trials continued until 30th September 1938 when the tank was returned to the Experimental Workshop for its final adjustments. On 16th January 1939 the tank was tested again completing a short distance trip to Lowicz and then between 22nd and 25th April travelling past Grodno to a distance of just under 400 miles. Once a total of nearly 1300 miles travelling had been logged the tank was completely stripped down to check the wear on particular elements of the vehicle.

In May 1939 the tank was refurbished and presented to the military hierarchy.

The military loved it and approved it to enter production but before the tank could enter mass production Germany invaded Poland in September 1939, ending the independence of the Second Polish Republic.

The Construction:

The tank had a classic rear drive layout. In the front, the drivers compartment was not separated from the combat compartment which contained the turret. An engine compartment was at the rear with a longitudinal engine. The 10TP had a complement of 4, with the driver sitting front left and machine gunners post on the right. A commander and gunner had their stations in the turret on seats that turned with the turret.

A forward hull plate was sloped, broken by the sloped machine gun casement and two side casemates which may have been there to provide a measure of protection from sideways fire and incidental projectiles such as shrapnel.

The water cooled heavy machine gun in the casemate was mounted in a big housing with an armoured mantlet and armoured water radiator.

A two part drivers hatch was in the remaining slope area of the front upper glacis plate. Hull sides were vertical and the rear plate above the engine was heavily sloped.

The turret had a one part hatch in the roof and a rear niche for a radio or extra ammunition. There were vision slots in the turret sides that could also facilitate pistol shots and the commander had a reversible observation periscope wz.34 in the turrets roof.

The tank was also armed with a Bofors wz.37 37mm anti tank gun that was proof against all known armoured vehicles at this time and was mounted alongside another 7.92mm wz.30 coaxial heavy machine gun. The turret had a 360deg arc of fire and the gun elevation was from -10deg and +20deg whilst the 10TP was stocked with 80 rounds for the main gun (APHE and HE) and 4500 hmg rounds. Both weapons were equipped with telescopic and periscopic sites.

Armour was provided by riveted and welded rolled plates with thicknesses between 20mm and 8mm.

The Sculpting

So, when I decided to start this one I was, to say the least, intimidated! This is a complex beast with all manner of different surface details. I suppose the one thing that was really in my favour was the lack of curved surfaces which, without computer algorithm controlled casting processes is very VERY difficult for an amateur to pull off!

Half way through collecting my early war Soviet army I just happened to ponder how close the BT-5's wheel and track assemblies were to the 10TP and I was delighted to find that apart from the details on the wheels themselves there was an almost identical correlation between the two... which meant I could appropriate one for the other, thus overcoming the only real deal breaker in the project.

I happened to have a spare Battlefront 7TP laying around and as I couldn't really be bothered to sculpt another sloped turret (after my Vickers E experience!) I though I may as well use that as well, as I intend using its track sections for my C7P (more on that later) so that was the second short cut taken care of!

All I really had to do was sculpt the hull... I set to work about a week ago, and you will have seen the basic shape on my previous post.

I have now found myself using a range of different materials in my sculpting with styrene and brass being used alongside each other all the time, although I think my favourite material is the Magic Sculpt two part epoxy resin that I use to square in disturbed edges, provide transitions between rough areas and to regulate surfaces. 

I freely admit I'm not great at this yet but practise makes perfect right?

The wheels needed very little adjustments to them other than the rear drive sprocket having a considerably different design to that of the BT-5. There is a welded hexagonal plate that sits over the hub which still needs to be done... but one thing at a time. The most prominent difference is the layout of bolts on the main wheels. The BT-5 doesn't have may bolts on them whilst the Polish ones have got SO MANY BOLTS PER WHEEL that its hard to imagine that these wheels would shatter explosively hit with anything larger than a toffee hammer! Anyway, it took me a whole night to punch out all of the rivets that I needed and glue them to the wheel and track assemblies.

So in reality the majority of styrene modelling is all about accurate measurements and being able to glue tiny pieces in tiny places and being able to clean up your mess before the glue dries but for me perhaps the most awkward pieces was the engine mesh covers. I decided to use brass textured mesh packed out with resin and then sanded back so the texture and shape was preserved whilst leaving no edges that mould silicon can get trapped behind.

... and in case anybody is interested, this particular model measures 6cm by 2.5cm. Pretty small huh?

Use in Flames of War

Organisation of platoons and companys should be just as listed in Alex's Poland in Flames for the motorised brigades with the following statistics:

Mobility                                Fast Tank
Range                                    24"/60cm
ROF                                      2
Anti Tank                              6
Firepower                             4+
Front Armour                       2
Side Armour                         1
Top Armour                          1
Equipment and Notes           Hull mounted MG, CoAx Mg

... and there you have it guys... onto the C7P!

Fix Bayonets!