GPM K5(E) "leopold" 1:25

Hi,

Although I'm still working on the PzKpfw III and 3 other models (SdKfz 250 Greif, SdKfz 252 and the Stug) are still lying on the shelf unopened, I could not resist to buy the Leopold.

Once the model arrived, I started to realize that the finished model will be over 126 cm long. Actually the model will not fit into my glass cabinet, but I'm sure I will find a nice spot to display it.

The quality of the model is really good, regarding the way everything fits together as known from the GPM models.

The manual is in Polish, German and English which makes it easy to read. In the manual it is not depicted when parts have to be painted on the backside. So I needs some attention, since once the parts are glued together you can't reach some spots anymore.

The model also has some mistakes that I don't like.

- The camouflage is that of the displayed gun in the USA which is not historically correct. Therefore I will repaint the whole model in a correct color (yellow/light brown as used in Italy, or gray as used in the rest of Europe and Russia). I did not decide yet, but I think it will become gray.

- The text on the model has some spelling errors and after painting the model I will put it back (without errors ) Since the text is to small to paint by hand, I will buy custom made decals at http://www.blackliiondecals.nl

- Every wheel of the model has brakes, whereas the real one had no brakes on the middle two axis of each car. I will restyle the brakes and fit the correct number.

- The box on the last car is called ammunition storage, but this is really not true. The box contained an engine connected to a generator to power the gun as it was disconnected from the train before shooting.
The crane did not lift the projectiles from this "storage" but lifted the small trailer on top of the gun. The projectiles were prepared in 3 other cars (ammunition storage, charge storage and charge pre-heating). These projectiles were than loaded onto a small trailer which was pushed by hand to the back of the gun. Then it was lifted onto the gun and pushed forward towards the gun-breach.

Also the projectiles did not consist of 1 part as in the model, but out of three parts (shell, propellend charge in cotton bag, propellend charge in brass container with the primercap).

I will close the top of the box and will fit a generator inside which will be visible through the open doors.

For the rest, I will add more details that are not in the model.

As a reference I will mainly use:

http://svsm.org/gallery/280mm-leopold-family
http://www.one35th.com/model/k5/k5_frme.htm

All these corrections and adding more details, requires repainting the whole model with Marabu-buntlack spraypaint. Before I build and spray the whole model I will first test the paint on all the materials I want to use (woodglue, white glue, superglue, metal, plastic, paper, cartboard etc). Since I don't want to find out that the paint will come of after painting the whole model.

Some pictures of the Leopold as a plastic model:

Xander

Here the bottom part of the car with the generator.

I will stop building now, and test the paint on this part of the model.

If it goes bad, I can easily build a new frame.

Xander

HI thunderpig,

In total the model has 24 wheels. One of the reasons the panzer I'm building is still not finished is because of the wheels. I really don't like mass production of one item. But it has to be done.

For the Leopold I have checked Drafmodel but they don't have lasercut wheels. But because I have now a computercontrolled milling machine, I can make parts myself out of hard cartboard or balsa wood.

On the otherhand, the wheels consist only out of 5 or 6 pieces and are really easy to build compared to those of the panzer. So mayby I stick with the paper.

The brakingpads I'm definitly making out of wood using my milling machine.

Here is a picture of a similar machine I have to cut parts

Xander

Hi,

I tried to spray paint on the part shown in the pictures before.

Because of 2 reasons, this became a disaster.

1. It was my first time using spray paint. And I applied a layer that was to thick. Meanwhile, I read on plastic model sites that you have to apply a couple of really thin layers. The layers must be almost invisible when you apply them. After a few layers you will end up with a complete coverage without dripping of the paint.

2. The paint I used is not compatible with the inkt used in printing. Some chemical reaction causes the paint to change color and crackle.

The final result is that I will build this part of the model again and in the meantime I tried different ways of painting.

I found out that first painting the model completely using a brush with acrylic paint, than sanding off the paint almost completely (leaving a realy thin layer of paint) and than using the spray paint in multiple thin layers gives a really nice finish.

I must admit that I tried this procedure only on a small test sample of about 10x10 cm. And I need a lot more experience before I will spray the big parts of the Leopold. Especially the sides of the gun are big, 80 x 15 cm and they have to be painted evenly.

In the meantime I also got a book about the Leopold. This is well documented and with detailed pictures. It will help me putting more details on the model and correcting some mistakes.

Leopold 28cm K5 (E)
Armor PhotoGallery #12
By Jan Coen Wijnstok
Published by Model Centrum Progres, Warsaw, Poland
ISBN 83-920254-5-8

http://www.perthmilitarymodell…views/books/apg/apg12.htm

Since I always read a lot of information before/while building a model, I must tell you that within their possibilities, GPM did a realy amazing job in creating this (and also other models) although they made some small mistakes.

Xander

Hi delcom,

I indeed used a spraying spray can. For the large pieces it works out really well. For the small details, I will apply paint of the same color with a brush.

The problem was not the spray can, but the chemical reaction between the paint and the inkt. When I first treat the inkt with some other acrylic piant, everthing works well, and I get a nice smooth finish of the desired color.

Today I tried again with the sides of the gondola. It is first painted with acrylic paint using a paint roller. Since the sides consist of 3 pieces, there are 2 seams between them. These I tried to fill and smoothen down using sandpaper, but they are still visible.

After sanding the seams again, I will spray the sides with the spray can.

Xander

Hi,

One side of the gondola is now finished, the left side needs only the outer layer.

About the side, Stefan is right, it becomes really big. I already run into problems since I tried to build both sides of the gondola at the same time, but that would take about 1/2 square meter.

The allignment of the parts is a bit problematic allthough the quality of the model is really good. But since all the errors add up (and I don't want to end with a gun that is not straight and/or square) I paid a lot of attention in making everything as good as possible.

The outside of the gondola on the left looks not straight (bottom part of 3th picture) but that is not the case.

The white sides of the gondola will be spray-painted once the other side and the bulkheads are fitted.

Xander

Hi Thunderpig,

I'm still building the gondola. As I told in my last post, the allignment of the parts is really crucial to make everything straight.

Although the parts are really strong, due to the 1 mm thick cardboard and all the cross-connections, the model still tends to bend during construction.

Therefore I builded a jig even bigger than the condola to hold all the pieces together while drying. Now the error is smaller than 1.25 mm over the full length of the gondola.

At the moment I'm adding some details to the gondola and then it is ready for the paint job.

If I had to build the gondola again, I would take 1 mm thick plywood instead of cardboard. This is maybe not acceptable for the purists but it will make construction a lot easier.

I'm looking forward to your building report.

If it really takes you 1 or 2 years to start building you can watch me making all the mistakes and learn from that ;).

About the spelling mistakes, that is why I decided to paint the whole gun gray and use some water-transfer decals. Another advantage is that since I have to paint the model, I can change all the mistakes in the model as mentioned in my first post.

Are you going to build the model right out of the box, or are you also going to make changes?

I thing that the biggest mistake (the fact that the generator room is used as ammunition depot) is really easy to correct. Just close the top of the generator room.

As soon as I have some spare time, I will post pictures of the current status of the model

Xander

Hi all,

Since I'm really busy with writing my PhD thesis, there is only a limited amount of time available for modelbuilding. Allthough the progress is small, I still want to show you the results.

The first picture shows the enormous size of the railway gun compared to a 1:25 figure and T34 tank. Note that there has to be a second railwaycar added to the back, but I have not yet started building it.

The second picture shows the projectile and all the propellent charges nessecary for a single round. The full set of propellent for maximum fire range consisted of a main charge in a brass container combined with two big and a small charge in cotton bags. For shorter ranges less propellent was used.

The last three pictures show the end of the gun barrel with the attachement for the elevation mechanism and recoil brakes. The breach is made such that it can be opened which allows to put the gun in two settings in the final diorame (1. gun with the barrel lowered and the crew loading the gun. 2. gun with the barrel elevated and ready for fire).

Once the main construction of the barrel is finished, I will start adding details to make it look more like the real one. As I mentioned before, GPM made a really nice model, but some details are not present or not historically correct.

If somebody is interested in the changes I made/make, I can make some close-up pictures of these details.

Xander

Hi Piterpanzer

The T34 is downloadable in scale 1:50 for free on:

http://www.pluto.dti.ne.jp/~naka/news.html

I rescaled the model to 1:25

My building report:

Russian T34/76 tank from 1941

My T34 diorama:

T34/76 on a field road somewhere in Russia

Hi,

Since the detail on the barrel give me some trouble, I started building all 24 wheels. The way GPM designed the wheels is far from correct. Therefore I did some measurements on real wheel and a survey on the internet to scratchbuild new wheels.

The first picture shows the first 12 wheels and a pile of parts for the other 12. Futhermore, I constructed a holder for holding the two wheels and one axle while glueing them together.

The last picture shows the one of the finished axles.

If somebody would like to know the measures of the wheels, please let me know and I will make a PDF with the parts.

Xander

Hi,

Some people asked me more details on the wheel and the holder.

I'm currently not able to make more pictures of the holder, but I will given allready the drawings I used for building the wheels.

Xander