Scratchbuilding a 1/9 scale Citroen Kegresse P19 from the croisiere jaune

0000H!

       The Engineer in me just did a backflip! I just love your creation and it's detail. Well Done!

Hi Steven,

thank you for providing more details about the building process. I repeat myself but i like your built very much.

Bye Matt

Hi Matt,

I never intended this build to be documented as a step by step process and therefore I apologise for the lack of detailed pictures of the different stages. That being said, i can provide you with some answers to your main questions.

Yes it is motorised and fully RC.

All parts except for some of the drive train were FDM 3D printed on a Anycubic i3 Mega s or a Prusa MK3S.

The differential is from REELY and bought at Conrad. The motor is from Pololu and bought localy. The RC receiver and remote are from REELY through Conrad. 

The tires are silicon rubber castings in a silicon mould made of a 3D printed master.

The drive shaft is made from a brass rod and machined adapter soldered on the shaft.

I hope this answers a few of your questions. Don't hesitate to ask for more specifics.

Cheers,

Steven

Hi Steven,

I would like to see pictures from the different building stages, parts for itself or the model before painting. After reading your posts again I still miss technical informations like is it motorized, are all parts 3D printed and so on.

Thanks in advance

Matt

Hi Matt, 

I already did some detailed overview a few chats ago. If you need more specifics then please tell me exactly what you want to know or e-mail me directly. See mail in previous chat.

Hi Steven,

your halftrack looks absolutely mindblowing. An amazing model ! Would you provide more details about the building progress ?

Greetings from Germany

Matt

Hi Joerg,

You can reach me by mail at the following adress:

piste@telenet.be

Hi Steven

I am Joerg from Duesseldorf, Germany.

As a child I had a little book about the citroen croisiere jaune - and my hole life I looked for books, videos etc. about the citroen expeditions. (now I am 63)

I do a lot of 3d printing - for example the land rover models of 3dsets. Great.

Would it be possible to get your STL files. Let me know your price and a way to get in contact.

Kind Regards

Joerg

Hi Stephen,

thanks a lot for the additional historical information, very interesting indeed. It sounds like you have had some amazing adventures of your own

Also thanks for the details on your work flow process to arrive at the completed model. I really admire your patience and CAD skills as well as your scale model building skills.

Have you had a chance to set out on any back yard expeditions with your RC Citroen?

Hi Pawel,

I use SolidWorks 2021.

I am based in Belgium.

Cheers,

Steven

Hello Steven!

What 3D software do you use? And can you tell us what country you are from?

Thanks for sharing and have a nice day

Paweł

Hi Gil,

Interbellum expeditions have always been appealing to me. It even took me so far as organising some expeditions myself for 15 years mostly in North African deserts. I covered Marocco, Algeria, Tunisia and Libia.

In my research for these expeditions I frequently encountered reference to several Citroen raids. They were conducted with special half tracked vehicles designed by Mr. Kegresse.

From the early expeditions in "black" Africa they turned to an Asian adventure for the last expedition. This expedition split up and were planned to join again on the Asian side of the Himalayas. The group destined to cross the himalayas was called group PAMIR and consisted of lighter vehicles that could be taken apart when the roads became uncrossable. In the end only 2 from the total of 7 half tracks were taken across, the rest returned to France. Even the last 2 half tracks did not make the rendez-vous with the Asian group and had to be abandonned somewhere in Gilghit and the crew proceded to join the Asian group on horse back.

So far for a little historie.

I found a lot of photo's in several books I bought of the subject and a lot of reference on a website of a Danish association of Kegresse enthousiasts. Here I also found technical and spare parts manuals with a lot of drawings and pictures.

Also lists with all the different models and their specification. This helped me out to determine the scale of the original photos.

I started with a photo from the normal Kegresse P19 used in the Pamir group.

I can import this image into my CAD software and scale it to make sure it is in real size. I always start in real size and scale down to the model scale I want, once the model is finished. I took the idler wheel and sprocked diameter as a reference to scale the picture.

Then I started drawing the overal dimensions like centre to centre distance for the wheels, position of the main parts like the hood, wind shield, radiator and so on.

I decided to tackle the track drive system first because this seemed the most challenging and would be the decisive factor to go on and finish the build. Because this will be a working RC vehicle , everything had to work.

This gave the following result.

I was lucky to also find cross cuts in the technical manual to determine the thickness and build up of all the elements.

From there I 3D printed all the pieces, fitted them together and tested the assembly. It worked out fine.

In a next post I will take you further into the designing of the drive system with track and working differential.

If you have further specific questions, feel free to ask.

Bye for now.

Steven

Thank you for your kind words Jim.

Very nice work Steven!

Jim 

Stay Safe.

Hi Steven, this is a really interesting subject that I was not aware of. Congratulations on an amazing completed build. I am curious about what your workflow was to get from photos to a usable 3D model. Again well done and thanks for sharing your work on this very interesting piece of history.

My pleasure!

Hi Pavel,

Hooray it works. Thanks so much for your help. 

Hello Steven!

What I did exactly was I clicked to look at one individual picture then I clicked on "share" (that funny arrow pointing to the right, between "the star" and "the arrow pointing down") and then I took the option "BBCode" (third option). I got this (EDIT: here I pasted the code I copied but it posts as picture - much quicker as in my original example):

IMG_6723 by steven_vandenberghe_ecomobile, on Flickr

Copied it (ctrl-c), then I went on this forum and when posting I used the icon labeled "Insert/Edit Image". I pasted the above into "Source" but I have edited the above down to:

https://live.staticflickr.com/65535/51710629254_fea2a6a13d_k.jpg

and then I just clicked OK, finished editing the reply and just submitted the reply. Deceptively easy, isn't it?

Have a nice day

Paweł

Hi Pavel, 

how on earth did you do this? 

Hello!

Let's see if I can do it:

OK, it's harder than necessary, but it can be done!

Thanks for sharing and have a nice day.

I see your Citroen is later than mine - from after when they shortened the drive shaft and put the live axle in front instead on the back, as in the earlier machines - like for example the one that drove around Africa.

Have a nie day!

Paweł

Hi All,

I updated the original post , the photos should be accessable now. 

I hope it works. I would love to embed them but I don't see how this is done. All help appreciated. 

Hi ,

I 3D-printed every single track plate and inserted steel pins. A lot of work. In the original model the track was made of a rubber endless belt with steel plates screwed on. Due to the constraints I had to make it a working model, I went for separate track links instead. I did not find an easy way of replicating the original layout and make it work.

How did you do the tracks?

Thank you for the suggestion. I did a test post of a picture I sent with the URL from Flickr. Still waiting for it to appear to check if it shows.....

Hello Pawel,

I am struggling with the pictures. After seeing nothing was diplayed I checked the Help section and tried again. I am on Flickr and added a photo in the Test section using the URL code. I am still waiting for the result to appear.

How can I edit my original post? I would love to rectify it once I find out how to get the photo's inserted. Someone mentionned "embed" photo's. How is that done? 

Thx for the help.

Hello Steven!

I'm also having problems with the links. You can edit your post to fix them. If you like I can help you with posting pictures here.

The title of your thread got me interested, because some years ago I have built a model of a very similar vehicle - a polish wz. 28 armored car which was built on a citroen chassis:

Good luck with those pictures - I would love to see them - and have a nice day

Paweł

Steven, your links are not working for me.

I find embedded pictures more reliable, as well as easier to access.  There are a number of threads on how to embed photos down in the Forum Technical Assistance forum.  It is in the Feedback, Help and Testing section of forums.