"Very nice sandy beach ... but the sea is really far !". French Aeronavale (Navy) Potez 25 TOE. 1934 "Pink Cruise"

[PanzerWomble]

Scared ....Hubert ???    

 

No ............we are all coming to your house when we need the 3 D stuff doing as clearly you're in your own league here 

[HubertB]

12 minutes ago, PanzerWomble said:

Scared ....Hubert ???    

 

No ............we are all coming to your house when we need the 3 D stuff doing as clearly you're in your own league here 

You're welcome PW

You playing golf ? I live on a golf course, and the weather here is generally much better than in Ireland, Scotland or the UK in general. Golf is my second occupation now that I am retired.

Hubert

[Peterpools]

Hubert

Hard for me to absorb and understand all the work so necessary for 3D printing, as for someone of my age, the work involved needs to be so incredibility accurate and precise, I shudder even thinking about ever trying to do it. 

I still tip my hat for you learning the skills so necessary for the level of work.

 

 

 

[PanzerWomble]

No golf for me sadly , like the sun though

Also like your Potez  

[HubertB]

Making some headway (at last) … the cockpit …with the Japy pump 

 

Well, after a few days wasted fighting a reluctant resin, some progress to show, at last

I think I can call the cockpit finished. I resisted the AMS urge to add more details like the command cables (which were doubled on the Potez 25). A sense check with the fuselage taped together and tje cockpit coaming in place showed that there was more than enough in place for what would be visible in the end.

Even the time spent trying to achieve a worn leather look to the seat cushions was not that necessary, as most is hidden by the safety harness 

I did add some variation to the wood finish with oils, pastels and inks. And I am happy with the aspect of the printed throttle quadrants and trim wheels. Better, IMHO at least, than the PE parts supplied by Lukgraph. The French Navy Potez 25 were liaison and servitude aircrafts, so no armament. The folded PE square on the right side of the main IP, which gives access to the machine gun breech on the fighting aircrafts, was filled-in with an additional instrument using Airscale’s bezels and instrument decals. I used the Lukgraph-supplied decals for the other instruments, but thecompasses, where I felt the decals were a bit too bland, and Airscale’s products came to the rescue again.

And I added the radio sets I printed, duly painted.

Anyway. On to the pics :

 

 

 

 

 

But wait ! The Potez cutaway drawing of the « Black Cruise »  Potez 25 - and my bet is that the « Pink Cruise » ones were no different in that respect - indicates clearly the presence of the Japy pump. I am sur you have all seen these pumps, used for manual transfer of a liquid from one container to another. For the Sahara flights, the Japy pump was used to fill-in the fuel tanks from the barrels. 
What is amazing is that Japy, a French company, still exists today, and is still producing the same hand-pumps (plus a raft of other pump devices) than a hundred years ago. So, I had no difficulty finding reference drawings with dimensions, to design a 1/32 Japy pump, and print it. 
I printed 5 for safety. They were - and are still - sold with a 1 meter-long plunger steel tube, and a 2 meters-long flexible tube to transfer the fluid to the tank. So I duly added them, on three of them.

And the Japy pump in its place in the cockpit :

 

 

Whilst I was waiting for oil paints to dry, I also prepared the fuselage halves for gluing them together. My concern throughout this build is to make it string to withstand the weight of the finished kit and its heavy one-piece main wing. I have added renforcement bulkheads where the cabane struts will be attached, and where the lower wing will be glued to the fuselage. Lukgraph has molded a recess for the lower wing, with holes for carry through spars. But this means the resin at the wing root is very thin, when it will be bearing a big chunk of the aircraft’s weight. So I added some 2 mm thick plastic card on the inside, that will insert into the cockpit frames and make the whole more solid. By the way, the French aircrafts of yhe era were painted a dark « interior green ».

 

And I have also started painting one of the two key elements of the vignette

 

The blue background, and the bench lighting, do not help to see the color modulations, but I am pretty happy with it

TTFN

Hubert

[DocRob]

The interior looks super bueno Hubert. Worn and comfy like an old glove  with lots of details and different materials on show, always a highlight on era planes to me. Shame that not much will remain visible. You may like to think about, removing some panel/cloth on the fuselage sides for better insight.
The hunchbacked desert mule looks also good. Spot metering is the key for showing the modulation better.

Cheers Rob  

[HubertB]

3 minutes ago, DocRob said:

[…] Spot metering is the key for showing the modulation better.

Cheers Rob  

With a camera, yes, Rob.

But I have only my iPhone ATM.

Hubert

[DocRob]

2 minutes ago, HubertB said:

But I have only my iPhone ATM.

Try tapping on the object of desire on your screen while using the IPhone, it helps sometimes with better light metering. There are better camera Apps out there as well. I use ProCam, which is cheap and enhances the possibilities of the Iphone camera.

Cheers Rob

[HubertB]

Following Rob’s advice, I played with the editing of the camel pics. Below are some pics that are more representative of the real life camel model …

 

And the pic of the Japy pumps :

And the pump in situ

 

Hubert

[Landlubber Mike]

Wow Hubert, really nicely done!  The interior looks incredible, fantastic work!  Also love the camel - I bought a set from CMK and might use one in my Sandbox dioramas.

[CANicoll]

Hubert,  Definitely looking good!  Photography much better too.  🙂

[Peterpools]

Hubert, incredible progress and nothing has escaped your eye. 

Thoroughly appreciate the narrative of not only your progress and work but of the historical highlights you have uncovered so far on your journey; the pumps are a great story.

  

[CANicoll]

That narrative is what really adds value to these build threads.  I love it!

Not to mention, your build technique is excellent - the work you are doing is beautiful.

Edited October 19 by CANicoll
Update

[KevinM]

That is looking exquisite Hubert really liking it a lot.Golf...I use to play quite a bit back in the 90's my older brother would always win except one day my best round I am thinking 87.I usually was like 95/105  terrible but it was fun then the green fees started going up.I took up gun collecting they do not go down in value.Keep modeling Sir the work is fantastic.

[HubertB]

She’s got skinny legs, a fat belly, a flat nose with big nostrils …

…but beauty is in the eye of the beholder, right ….🥴 ?

I have reached a significant milestone in this marathon conversion : the fuselage is now closed, and the major conversion parts added.

But first, some pics of the new undercarriage, with its brass rods reinforcements. After my geometry blunder, I changed the approach, and split the undercarriage design in two halves, with a front and a rear half. I could thus add the brass reinforcements rods whilst respecting the planned geometry. Brass loves CA glue, so that makes the build both easy and sturdy. Some in-progress pics :

It looks good on the pics, but in fact the rear diagonal struts link to the main axle proved a bit flimsy, especially split in two halves. They did not resist the assembly process, especially as, although the cavities in the undercarriage struts were dimensioned with a margin, the mating with the other half resulted in some gaps to fill and sand. I resorted to cheat a bit with scale accuracy, by making the mating point larger in scale than it was IRL. I added some Milliput lumps which allowed to ensure a strong joint when regluing the rear struts in position.

I could close the two fuselage halves, trapping the cockpit structure in- between. After this operation, I found a slight design issue with my conversion parts : when measuring the (flimsy, after cutting chunks of it) fuselage halves, i designed my parts around a 27 mm width. When they were mated together, I found that the width was in fact 28:mm   . But the good thing about designing and printing your own parts is that accurizing them is a fairly easy operation. I had to re-design the under cowling with an extra mm width, and then the radiator to fit the larger nose. The lower fuselage fairing was too narrow at the rear end, also by a mm, and that was also re-designed and re-printed.

And that is how it looks tonight, when assembled. The undercarriage had to be inserted before mating the new lower nose. I can confirm it is strong. Hopefully, it will remain strong when the weight of the main wing is added 🤞.

The radiator is only loosely placed, as is the cockpit coaming (more on that later) and the fin - which is dutifully offset a few degrees to starboard, a point overlooked by Lukgraph, but visible on the factory drawings.

 

 

The supplementary belly fuel tank is a solid chunk of printed resin, and I found that it had warped somewhat after a few weeks. This seems a more common issue with thick 3D-printed parts than one would think initially, apparently. I did not bother re-printing one : some filler and agressive scraping and sanding cured the issue, os in old-style modelling 😂.

And the sharp-eyed among you will have noticed that the very thin resin of one of the undercarriage struts got partly broken off during the gluing, or sanding, process. Oh well, it is easy to repair, either by cannibalising an other strut - I have printed a few - or adding some properly shaped Milliput

Now about some experimentation. I mentioned in an earlier post that I still had to design the windscreen parts. They are a fairly involved design, especially where they meet the fuselage. I ended up designing them in situ on the cockpit coaming, and decided to try to print the whole part in transparent resin.

When it is coming out of the printer, clear resin is cristal clear. But the washing and curing process results in a more cloudy appearance. This is due to the printing lines, which generate a small light diffraction. However, the transparency can be restored somewhat, by buffing the part, and coating it with clear varnish.

After a few trials, which involved trying different clear resins, different thickness for the print layers - 20, 30 and 50 microns - and different varnishes, as well as some buffing, I found what I think is a satisfactory solution, especially as we are looking at a 1930’s aircraft on a long-haul flight though the - dusty when landing and taking off - Sahara.

 

 

I believe I can improve even more the transparency by some gentle sanding and buffing and then adding a second layer of varnish, btw. Now the masking is going to be « interesting » 🤪.

Hubert

PS: on the pics above, only the windscreens have been varnished. The rest will be painted, so transparency is not a requisite.

[GusMac]

Great problem solving Hubert. The transparent coaming looks excellent.

[DocRob]

I can imagine, how hard it is to get all the measurements of the fuselage parts right during the design process. It´s so easy, to miss a millimeter here or there, but it definitely shows when mounted. 
Clear resin looks pretty good and your build log is a clinic for 3D printing, a way, I´m not willing to take myself right now. I can see myself designing and printing smaller parts, but not whole kits. In my case it could also be troublesome to get the needed materials, so I will relay on AM producers or just buy MFH kits .

Cheers Rob

[Martinnfb]

Never mind the aeroplane, the camel looks real.

[HubertB]

36 minutes ago, Martinnfb said:

Never mind the aeroplane, the camel looks real.

That's his (her ?) buddy in progress. When in Marrakech 6 weeks ago, I noticed the color variations of the dromedaries there. Some were greyer rather than sand, so this one will have a different hue, lighter and greyer. It's (realistically) a male, btw 🤣

 

 

Hubert

[HubertB]

Time to be cautious ... brave ... cautiously brave ... brave to be cautious !

Since I have started working on the Potez, my main source of worry has been this :

The main wing is not only large (about 45 cm wingspan), it is also thick, and Lukgraph have molded it in three pieces (center section and two outer panels). So that means a lot of resin, and therefore some weight, as you can see - That's about 6 oz for our anglo-saxon cousins -.

It is supported by 4 cabane struts and 4 interwing struts, which I have already re-printed to have not only the right angles, but also to be able to insert some rods into them. Lukgraph's resin is nice, easy to work with, and keeps good detail. But it is also quite flexible. Which means the lower sequiplane wing that will carry a chunk of the weight of the main wing will be under some load, and I am not trusting the resin to hold itself straight over the course of months.

I had drilled some long (about 35 mm) holes ion the lower sesquiplanes, to insert some brass rods that will go through the fuselage (itself duly reinforced) to help support them). But there was still a bit of overhang (about 65 mm) between the end of the "spar" hole and the attachment point of the interwing struts. Enough to worry me about the long term flexion.

So it was time to be brave and get heavy duty tools to butcher the kit again !

I milled some slots in the bottom of the lower sequiplanes, up to the attachment point for the interwing struts. I then CA glued some 2 mm dia brass tubes in the slots.

The milling was a bit too enthusisatic, btw.

I have then filled the slots with Milliput. I will have to restore the profile, and above all the rib tapes, but this is where Archer will come to the rescue.

 

 

I have chosen to glue tubes, because I can then insert a 1 mm rod in the tube, that will go through both wings and the fuselage wing box, and make both sesquiplanes "bonded" together in the wing box.

Hopefully, it will be strong enough now. And even more hopefully, the landing gear will hold under the 350 / 400 grams weight of the completed model

Hubert

 

[Landlubber Mike]

This is looking spectacular Hubert - well done!

[CANicoll]

Excellent solution!  Looking forward to how you use the Archer bits, too.

[HubertB]

12 hours ago, CANicoll said:

Excellent solution!  Looking forward to how you use the Archer bits, too.

I built my stock of Archer decals before Woody retired. One of them is to represent the stitches in rib tapes of WWI aircrafts.

In fact,  when checking the Lukgraph’s wings through my Optivisor, the rendering looks more like rivets than stitches. Not really accurate or representative of the real aircraft, which was very much « updated » WWI technology. But I will go, for consistency, with the kit’s depiction, for the sake of simplicity, even if it’s a compromise with scale accuracy. I am trying to educate myself in fighting my AMS, by putting myself in the shoes of the casual viewer … Not always easy 🙄 …

In passing, I discovered some « interesting » issues with the slicing software (Chitubox) for 3D-printing.

The historical file format for sending 3D-created parts to a slicer was .stl (for stereolitography). It produces a « map » of the 3D voxels of the part. Based the resolution  you define for exporting your file, you can end up with VERY big files. For instance, the cockpit-coaming part with windscreens results in a close to 9 Gb file in the highest resolution …

Which is why I chose to export the files in a .obj format, which is a kind of 3D-vectoring format, and produces far lighter files.

BUT, I found out that some of my parts imported in Chitubox with a .obj format had a strangely-faceted appearance. I thought it was a display artefact of the software, but it is not. The facets are visible on the printed part, when they are not on the designed part. And they are not visible, either on the software display or the printed part, when in imported in .stl format. 
Another lesson learned : the display of Chitubox is not « simplified » but an accurate rendition of the future printed part. And It’s therefore better to go for .stl files. I need to fine tune the resolution of the export, though. High resolution is « heavy », and low resolution can result in round part appearing square - literally.

Hubert