HubertB

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

That’s a technique I would not use … Nothing makes me run faster away from the threat than Patricia using hairspray 😱 Hubert

Beautiful work Hubert

I'm not in Quinta do Anjo anymore (it was near Palmela on the Setubal Peninsula). I now live In Santo Estevao, 40 km south of Santarem, in an area called "Ribatejo". It's about 1 h 20 from your place. As you live near Tomar, bookmark the "Festa dos Tabuleiros" in 2027. Unique and absolutely a Must See. Hubert.

Out of curiosity, where have you settled in our nice hosting country ? Hubert

The forecast for the newt two weeks in Portugal is overall sunny, with a risk of rain just on November 1st, and temps ranging between highs of 23 Celsius, and night lows around 15 Celsius. And we have good beers, but frankly, wine is better and with a much wider choice . Enjoy your trip. Hubert

Most PU resins used for casting have shrinkage. The best ones are in the 3% (max) rangé but some can go to as much as 10 % shrinkage. Selecting the right resin, for casting easiness, pot life, pouring facility, and shrinkage is a challenge at least, or an art. And the silicone molds for casting have their own shrinkage to deal with … Hubert

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

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

Nice ! I love yellow wings, and even in the « wrong » scale 😂 Hubert

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.

Good to read. Thanks, Tim. Hubert

Looking great Gus. And the pic setting is totally adequate for the excavator. You really get an « in the works » feeling 😂 Hbert

I am with you guys. Great NMF and also the checkerboard 👍 ! Hubert

I remember standing under the wing of a Gannet in a museum visit. I was shocked by the thickness of the wing. Talk about the aerodynamism of a barn door 🤣😂😂 Hubert

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

With a camera, yes, Rob. But I have only my iPhone ATM. Hubert

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

In principle, the idea of sharing 3D-files seems a good idea. However, designing a 3D part can be time consuming, even if this is a hobby and we do not see the time there in the same way as working time. Sharing a 3D-file for free means the designer looses control of the whereabouts of the said file. And who says that the file will not end up in the hands of someone who will then sell the file to others for a profit ? We already see a lot of this with music or video creations. This is basically piracy of intellectual property. There are already some websites that share - for free or for a fee - some 3D files. This was also the principle of Shapeways, who also did the printing, but finally priced themselves out of the market. I have already shared some printable 3D files, and asked the recipient that he did not re-share, or worse, resell, the file. But it’s a game of trust. Doable on one-to-one sharing basis, but making files available through a website or forum is opening Pandora’s box IMHO. Remember the rules that had to be established for the Xmas raffle ? Just another proof that people profiteering from others’ generosity do also exist in the modelling world. Hubert PS: nice progress Jeroen. Sorry abou the thread drift.

… And the first car to go above 100 kph, 125 years ago, was electric : La Jamais Contente. Hubert

Definitely for SMall pARTs Hubert

Plus, in my experience, all the paints of the Vallejo galaxy are difficult to thin. In theory, water should work, but it’s not that great. Most other thinners, but for Vallejo’s own thinner, will result in a goey mess. I really love that I can pour MRP paints directly in the airbrush cup. Plus they spray beautifully. Hubert

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

Thank you Rob. I do not want to scare anyone away from trying 3D- printing. Truth is it can be very easy - both machine manufacturers and slicing software developers work hard for that - and you can get a success (almost) everytime, But it can also be extremely frustrating when using the same parameters results in a failure when it was a success the day before. I think you should read from all my errands that I am not as good as some said in this thread . Ruffling my feathers to send me back to the ground is not a bad thing , even if the landing may look more like a crash sometimes 😂🤣😉. Anyhow, I am now back to good printing results. FWIW, Anycubic’s « Translucent green » resin has proved to be both a high resolution and a fail-safe product, again, as I used it a few years ago for printing my Travel Air Mystery Ship. I intend to try a bit more modulation in the cockpit and follow your ideas. Right now, I shot some primer on the newly-printed cockpit-détail parts like the throttles or trim wheels. Modulation trials comes this afternoon. And I designed and printed yet more new parts for the Potez. I was wondering how Lukgraph had managed to print the wing and cabane struts hollow, in order to inset a reinforcement rod. Well, they have not. The holes are only about 8 mm deep. I managed to drill a complete hole in a 60 mm long strut, but it was tedious, frankly, and I was lucky to be able to - almost - meeting holes when I was drilling the strut from both ends. And then I realised that Lukgraph had the struts wrong anyway. They are angled outwards. Lukgraph says it should be 27 degrees. A drawing in the « Potez 25 » book shows 39 degrees, and is wrong, but checking on pics and the Potez factory drawings. I found the right angles, both from the front and from the side. And the print this night worked great, including see-through holes for the reinforcing rods. So far, I have designed and printed some 30 different parts for this project. i have still to design the pilot and passenger windscreens and print them in clear resin. More later. Hubert

She’s looking good Kevin Hunert