IBG PZL P-11c modified to P11/IV prototype. Reigniting the building process ...

[1to1scale]

That’s awesome!

[DocRob]

Iike Gaz said, nice work and thanks for the comparison of the Bitskrieg bits and kit parts, I haven't decided, which I will buy for my PZL. The radiators for sure.

Cheers Rob

[HubertB]

Thank you for the interest and following along. Much appreciated.

Well, progress. I have sprayed some primer on the parts that will be silver later.

Having read so many positive comments about them, I ordered and received last mont some MRP paints. So this was the opportunity to try the black primer I had ordered.

Let me summarize my feelings about these paints after this session : wow !

I am sold ! Everything you have read is true, and even more ! They spray beautifully, directly out of the pot, without thinning, and the result is incredibly fine and smooth. Me a VERY happy camper !

Some pics to show the results. Everything is black, so the contrast is not that great (now, THAT is an understatement), but you will get an idea (and my pics suck anyway )

And the last bit, the cockpit frame :

By the way, on the first pic, don't do as I did. Read the instructions first, and do not glue the visit panels BEFORE the guns have been put in place. They are inserted from the outside, through the openings !

Hubert

[HubertB]

Well, the cockpit has been painted. Some touch-ups to do, especially the red spots for the various knobs that were in this colour.

The basis is white aluminium. The reliefs have been accented with some Tamiya black and brown "Panel Line accent color.

I am shooting the pics with my iPhone, it's hard to get the wole subject in focus, and the colors true ... Need to fetch that digital camera as soon as I remember where I put it in the move ....

 

Progressed on the engine as well. This is the Bitskrieg engine. The balck base has been drybrushed with Humbrol flat alumimium, then the reliefs accented as the cockpit with Tamiyablack and brown accent line color. Some touch-ups still to do ...

 

I hope you like it.

Hubert

[harv]

WOW....harv 

[Bomber_County]

Hubert, you’re making this all to easy.........stunning.....

[Marcin_Matejko]

Hello Hubert, congratulations on taking on the rather difficult task of converting the late P11c into the fifth P11 prototype. As I am preparing for the same task, I would like to draw your attention to a few things that made this plane different from serial planes. First of all, it had a different engine, it was not the Bristol Mercury but the Gnome Rhone 9Krds engine. For this reason, there was a different exhaust manifold, a slightly longer engine crankcase and a slightly different propeller cap. The undercarriage covers you made so beautifully should cover slightly different wheels, which were smaller in diameter and a little wider. This plane did not have a radio station, therefore there was no door for the radio station behind the pilot's cabin in the fuselage. There was also no internal structure to hold the radio within the hull. There were no radio antennas and no mounting elements for the fuselage, wings and fin. This plane did not have bomb launchers under the wings. It also had a slightly different aileron design than serial airplanes, and the horizontal tail had a different shape, it was more convergent. There were probably more differences, but the documentation for this prototype does not exist and there are also very few photos.

Good luck with the further construction, best regards Marcin

PS. These are my two 1/32 scale models PZL P6 1931 and PZL P11 the third prototype 1932. Both are made from scratch.

[HubertB]

Just now, Marcin_Matejko said:

Hello Hubert, congratulations on taking on the rather difficult task of converting the late P11c into the fifth P11 prototype. As I am preparing for the same task, I would like to draw your attention to a few things that made this plane different from serial planes. First of all, it had a different engine, it was not the Bristol Mercury but the Gnome Rhone 9Krds engine. For this reason, there was a different exhaust manifold, a slightly longer engine crankcase and a slightly different propeller cap. The undercarriage covers you made so beautifully should cover slightly different wheels, which were smaller in diameter and a little wider. This plane did not have a radio station, therefore there was no door for the radio station behind the pilot's cabin in the fuselage. There was also no internal structure to hold the radio within the hull. There were no radio antennas and no mounting elements for the fuselage, wings and fin. This plane did not have bomb launchers under the wings. It also had a slightly different aileron design than serial airplanes, and the horizontal tail had a different shape, it was more convergent. There were probably more differences, but the documentation for this prototype does not exist and there are also very few photos.

Good luck with the further construction, best regards Marcin

PS. These are my two 1/32 scale models PZL P6 1931 and PZL P11 the third prototype 1932. Both are made from scratch.

Hello Marcin,

Thank you for your feedback and comments.

I followed, in awe, your build threads of the early PZLs. Your work is absolutely outstanding, and far above what I am attempting.

As far as the engine is concerned, I went through the documents I had about the prototype I want to represent, as I had some concerns about the way the cowling was painted, some representations having what would be the frontal exhaust ring of a Mercury engine painted, which would be an aberration given its nature.

From what I have read, I have come to the conclusion that the prototype shown in Paris had indeed the Mercury engine, which was a bit of relief, in all honesty - I just hope it was not wishful thinking from my part  .

Thank you for the data on the wheels and radio compartment panel. I have been sidetracked lately by my experiments at 3D printing the components of a Travel Air Mystery Ship and a P&W R-985, but at least I have learned that designing and printing wheels is among the easiest things of kit design  . I now need to find a way of removing the panel line of the radio compartment hatch without destroying the adjacent surface details.

And in fairness, I’ll probably live with the kit’s stabilators, unless I can figure a way of designing a new one consistent in surface detail with the kit.

Please do not hesitate to contradict my engine certainties for the Paris Air Show bird, if you have the data.

Hubert

[Peterpools]

Hubert

Awesome work on the interior assemblies and front office .. looks fantastic.

I started using MRP paints when they first where available in very limited supplies on our side of the pond and fell in love with them. Colors were limited and when a specific color was sold out, it was months and months before there was a restock. I shoot them straight from the bottle for most of the colors, sometimes add a bit a Mr Color Leveling thinner when the mood strikes and always add a drop or two of Mr Retardrer Mild to the AB - the paint /primer goes down even smoother.

These days, I now always wear a respirator and shoot in the paint booth.

Keep 'em comin

Peter

[Marcin_Matejko]

The plane shown in Paris was a prototype that tried to interest the French. But Romania got interested in him, so he was sold to Romania. It was a model for the PZL P11F aircraft, about fifty aircraft of this type with GR engine were made, which were used by Romanians. The aircraft was offered for sale or license with a Bristol or GR engine. However, at the exhibition in Paris, this prototype had a sink GR 9Krsd. The P11C series copies already had a Mercury engine.At the moment I am collecting materials about this aircraft, but in this photo, although it is of poor quality, you can see that the engine heads are shaped like GR and not Bristol:

 

[HubertB]

2 hours ago, Marcin_Matejko said:

The plane shown in Paris was a prototype that tried to interest the French. But Romania got interested in him, so he was sold to Romania. It was a model for the PZL P11F aircraft, about fifty aircraft of this type with GR engine were made, which were used by Romanians. The aircraft was offered for sale or license with a Bristol or GR engine. However, at the exhibition in Paris, this prototype had a sink GR 9Krsd. The P11C series copies already had a Mercury engine.At the moment I am collecting materials about this aircraft, but in this photo, although it is of poor quality, you can see that the engine heads are shaped like GR and not Bristol:

 

Wow ! I had not found this pic anywhere ! Thank you ! And dang, you are absolutely right ! So now, I have to modify the engine, or forget about my intended scheme, which is unlikely, because, frankly, olive drab schemes are not for me  .

I was procrastinating about a trivial issue, which was how to represent the ignition harness ring of the Mercury, not being convinced about the IBG-supplied PE. it’s good I did, in the end. Now I « just » have to design the GR engine, then 3D print it. At least I can focus on the cylinders (a bit of my nemesis, as I stalled for 5 years on the design of the P&W R-985 cylinder head) as most of the rest will not be that visible.

I owe you a printed GR, for pointing me in the right direction. Follow this space and just ask me when I’m ready, if you are interested.

Hubert

 

[Marcin_Matejko]

I am glad that I can help. Thank you for the proposition to print the engine. I also go this way and design a 3D model of this engine, I haven't finished it yet, so far it looks like this:

Good luck :-)

Marcin

[Landlubber Mike]

Really nice work Hubert.  Thanks for the recommendation on MRP paints, I'll have to try them out.

[HubertB]

42 minutes ago, Marcin_Matejko said:

I am glad that I can help. Thank you for the proposition to print the engine. I also go this way and design a 3D model of this engine, I haven't finished it yet, so far it looks like this:

Good luck :-)

Marcin

You’re obviously far ahead of me in the design of the engine  .

If you want to share the file, my offer to print it for free still stands.

Hubert

[Marcin_Matejko]

Hello Hubert,

I'm working on the prototype drawings. Here you have the most likely silhouette shape of this prototype. At the top, a machine, at the bottom, a prototype. As you can see, there are some important differences that need to be included in the model. For now I am working on the remaining drawings of this prototype.

Greetings Marcin

 

 

 

[HubertB]

Thank you Marcin.

I have made progress on my own design of the G&R Mistral 9. I should have finished designing the cylinder in the coming week. Then it’s another few days for a good print  

 

I need to check your spats’ drawing against my interpretation. The problem is that I now have glued the legs to them.

And of course, I need to design and print a new long fairing for the new engine, and most likely a new cowling

Hubert.

 

[Marcin_Matejko]

The engine design looks perfect.

[Marcin_Matejko]

Hello Hubert,

I would like to apologize to you for the trouble with the engine. Because it turned out that the prototype of the fifth P11 from the exhibition in Paris in 1934, however, had a Bristol Mercury engine installed! In the publications that are available, on which I relied, the engine type is incorrectly stated as GR Mistral. Even the official catalog of the PZL factory is misleading by stating information about two engines on this GR and Bristol aircraft.

However, I managed to get to the American (intelligence) report from 1934 describing the planes at the exhibition in Paris. This report clearly identifies the P11 engine type as the Bristol Mercury VI. https://digital.library.unt.edu/ark:/67531/metadc65353/

In addition, we made a comparative analysis of the photo and it turns out that it is a Bristol engine and not a GR. You can see the characteristic of Bristoli split exhaust pipes. Another argument in favor of Bristol is the information board standing by the plane which shows (a bit indistinctly) the inscription "Mercury VI" Once again sorry for the inconvenience but this is last minute information. You can leave the engine from the kit as it is best.

Unfortunately, as a result of the war, Poland irretrievably lost most of its archives, which were either stolen or destroyed. As a result, the history of our pre-war aviation is incomplete and until today aviation historians and enthusiasts discover new information about Polish aircraft. We've just discovered a new detail.

Greetings Marcin

[HubertB]

Hi Marcin, 

Thank you for your new information. It’s no problem at all that you were misled for a moment. As the saying goes, « only those who do nothing never make mistakes »  . And it’s good as well that the documents I had read were not wrong in the end. The books I had read, from Polish authors, were affirmative about the 1934 bird in Paris being equipped with a Mercury, but your photograph convinced me that it could be a G&R Mistral 9. So we were brothers in error  : we both mistook twin exhaust pipes for rocker covers.

There are some positives about your intervention however, from my point of view :

1) Your pic has confirmed that the wheel spats had fairings to the gear legs. I had assumed they had, based on the contemporary P-24 pictures, but it was still some conjecture rather than a certainty.

2) I have learned some useful additional information like the lack of radio equipment and dedicated panel in the rear fuselage.

3) I have had to tackle again the design of a radial engine, and have in the process improved my skills with Solidworks, and used some new functions I had not yet used. It was not shake-and-bake, but it took me only a few working days to do so.

4) I will nevertheless finish designing the G&R Mistral 9 ( I am in the final stages of designing / fine tuning the « K » cylinder). This will open up some new possibilities, including scratchbuilding some ignored subjects. I always loved the look of the Morane Saulnier 225, for instance, and IIRC, it was equipped with the G&R Mistral 9 

5) This was an opportunity to confirm my move into a new realm of modelling. Now, I know I can design and print some parts fairly easily, and this is a great alternative to gluing bits and pieces for creating some scratchbuilt parts.

Keep the information flowing.

Hubert

 

 

 

[HubertB]

The "K" cylinder design is now complete.

This is what the full engine, sans the valve pushrod tubes, looks like.

Now :

1) I can resume the build with the original engine

2) I need to find an airframe to wrap around this engine 

Hubert

 

[Peterpools]

Hubert

Top notch work as always. 3D printing is way beyond my generation abilities and at 73, learning seems to be out of the question, as I'm happy to be able to solve simple computer problems at times.

Keep 'em comin

Peter 

[harv]

Ditto.....harv

[HubertB]

Well, now that the engine question is behind us, I came back to the issue of reproducing the ignition system of the Mercury engine. In truth, I had been procrastinating around this one for a few weeks, trying to understand where the ignition cables were originating from. Finding clear pics of the engine from the rear was a more difficult task than initially thought. 

I finally found a maintenance manual of the previous generation engine, i.e. the Jupiter, and in the same time acquired the conviction the ignition systems were similar from the Jupiter to the Mercury.

So, the Mercury had two spark plugs per cylinder, located laterally on each side of the cylinder head. And the ignition wires were routed to the base of the intake manifold ring. The cables from the magnetos also connected to the intake manifold casing, so I guess that, unlike their American counterparts, the Bristol engines enclosed the ignition distribution wire into the manifold casing, rather than have it as a separate part. For detailing the engine, we just have to know that the wires were touted from the manifold casing to the cylinder head.

First task was to drill 18 0.4 mm holes in the intake manifold part. No pic to show, as the holes are small, on a black-painted part. 4 bits later (a reminder that these small bits break like glass when subjected to side loads, and therefore mostly unsuitable for hand-drilling, where you can seldom avoid parasitic lateral movements. Only in this case, it was not possible to do anything else than hand-drill the holes  ), task accomplished !

Next, came the ignition wires. They are made of :

- a spark plug,

- a bent metal tubing containing the wire in real scale

- a braided cable going to the intake manifold casing.

To reproduce them in scale, I started by cutting 0.5 mm Albion tubes, 4.5 mm in length. These will make the bent tube. I will also need 10 mm long braided cable from AnyZ, metal wire, and 1.5 mm pieces of 0.9 mm tube to reproduce the plugs.

I introduced in them a small wire, approximately 25 mm in length, and  slightly less than 0.3 mm in dia, coming from an old electric motor, which will provide me a life-time supply of this wire.  
 

Next comes the bending of the tube. For this I used a special set of pliers made for bending wires:

With the wire inside, the small tube is not crushed :

 

The AnyZ braided wires of 0.5 mm diameter are actually hollow. You can thread the copper wire though them :

 

The braided cable is then soaked in position with thin CA glue :

Next the « spark plugs » are added at the other end. Whilst in theory a 0.7 tube will slide above the 0.5 one, in practice, with these small parts, 0.9 will save your nerves, and give you some leeway to adjust the angle.

I have not documented the addition of a small band of adhesive alu foil (cut from DYI tubing tape) around the top of the braided cable.

The wires are then painted : white spark plugs, and the braided cables are soaked in Tamiya brown accent line to break the yellow.

That’s all for now. Next step will be to glue the wires to the intake manifold.

Hubert

[Kaireckstadt]

Great research and implementation for the engine! Your skills are stunning!

[DocRob]

That's a truly beautiful ignition harness, great attention to detail and well described.

Cheers Rob