yvesvidal

I wanted to go back to the printing process and slicing of the hull parts. The nozzle of the printer is the standard 0.4 mm diameter. The filament is extruded at 200 Degrees Celsius from 1.75 mm diameter and kept under pressure in the extruder. The pressure will be quickly relieved when the nozzle has to move to a location where no filament is needed. Then pressure is applied back. I mentioned that the thickness of the hull is about 4 mm. In fact, the hull parts are made of a sandwich of two walls and some filling in between. All this is determined at the conception of the model and by setting the Slicer. I have watched the nozzle run its course and noticed that each wall is comprised of 3 runs. That gives us a total of 6 runs plus the filling in between. When the filament is placed on the hot glass surface and later on, on top of the part as it gets built, the 0.4 mm of the hot filament becomes 0.5 mm. This is called over-extrusion and is accounted for by the slicer program. The net result is that we have two walls totaling six times 0.5 mm in thickness plus a middle section of 20% filling and 80% empty. Again the filling is determined by the Slicer and set to 20%, to increase speed, reduce printing time and material (filament) consumption. Walls plus filling amounts to 3.0 mm plus 1 mm, giving approximately 4 mm thickness. Another interesting parameter is the printing height: it is typically half of the nozzle diameter, which is to say 0.2 mm. That is the increment in which the Z axis is building the part (vertically). For every 0.2 mm of material, we have six complete travelling of the nozzle (two walls), one Z shaped travelling (20% filling) and one additional travelling for details outside the hull, such as plates, rivets....etc. In summary, 8 complete sweeping of the part by the nozzle for every 0.2 mm on the vertical axis. For every millimeter, that translates to 40 passes.....Hull sections are 155 mm high....I will let you do the math...That is why some sections take 40 hours or more of non-stop printing. Yves

Craig, yes large ships made of metal are built in the same way: sections are pre-built and then assembled together. Same for planes. Yves

The delay is entirely due to the printer....😁 It is too slow.... Yves

Nice touch with the rollers for the coffin.... Yves

Moving on with the hull. Insertion of the coupling part between section 8 and section 7: You can appreciate the finesse of the fit. This model is designed for Radio Control but will be assembled as a static model, in our case. After a few hours of drying, I am starting to print some deck parts to see how this whole kit is fitting: The little bottle of Ambroid, gives an idea of the size of the hull: it is massive !! Yves

My brother, in the south of France, has a friend who owns a Velorex in working condition and fully restored. Yves

Starting with the Stern. As mentioned, I am using CA glue to secure the very large coupling part to the hull shells: Overall, it is not too bad. I will have to put some acrylic putty in some places, sand and I hope that after a couple of primer coats, the hull will be presentable. I will try to be more careful for the other sections. The trick is to lightly sand the inside surface of the hull shells and the contact surface of the coupling part, to make sure that the glue can adhere well. The fit of the coupling piece to the hull shells is amazing. Yves

I want to come back on the subject of gluing PLA parts, as we are experimenting: - My tests with MEK/Plastruct liquid glue are working very well for small parts. I believe the reason why it is so solid (like welded) is that the surface of each part is softened and fused, creating a very strong bond once dry. You still have to press very hard the parts for a few minutes. It does not offer the convenience and ease of Polystyrene bonding found on Plastic models. I will be able to use that gluing technique for the superstructure and small details. - For the hull parts, these are so big and so hard that the softening of the mating surfaces is going to require a very large amount of glue and time. So, I am resorting to Cyanoacrylate glue and two components epoxy for parts requiring fine adjustments. I think it will be overall more solid. I am also seeing different melting points for PLA of different colors (white versus light gray). The White seems very impervious to any softening.... - Other people have had good success with SCIGRIP 16 and specialized (and expensive) PLA glues. ACETONE is also an option although the fumes are nasty. I suspect that Acetone will evaporate too fast for large parts, anyway. - Some people use a 3D pencil, which is the equivalent of a welding iron, as it creates a 200 Degrees celsius bead of PLA, to bond two parts together. Results of course is not too sharp, as it adds materials and not strong either. Yves

Aon, The white couplers fit incredibly tight. Yes, I have tested the glue and it is ultra solid: the PLA is welded !! However, you have to put a lot of glue and hold the parts tightly coupled while the glue dries. I also noticed that gluing different colors PLAs is more delicate, as far as gluing goes. As you mentioned, in some places, resorting to Epoxy glue may be the right thing to do, for a nice and secure bond. Because the parts are so large, I have to use a brush to apply the glue and use capillarity to work for me. Yves

What a fantastic idea !!! Great artwork. I love the unusual subject, too. Yves

I would skip the inner planking (I think they call that "ceilings") and leave that beautiful structure plainly visible. Instead, I would concentrate on building some of the inner compartments and structures. Yves

Winnie, If you plan to put lights into this model (and you should do it), you will have to paint the inside of the walls with matte black paint. Otherwise, it will leak through the plastic or any white paint on the outside. Be very meticulous there and do not let a single area unpainted, on the inside. I had to fight this with my Trumpeter submarine and the Moebius 2001 Discovery space ship. Light leaks are ugly and ruin the overall appearance of the model. Yves

I love it Hermann. You are ahead of me, showing me exactly what to do.... Yves

A quick update on the Corvette Hull: As you can see, all the parts for the hull have been finally printed. We are talking of 2 weeks of non-stop printing. The hull is comprised of 9 vertical sections and one horizontal piece at the stern. They are labelled 1 to 9 from left to right. The section 3, 4 and 5 took between 36 hours and 41 hours each !!! The other sections have been detailed in previous posts. Overall, close to two spools of light gray PLA and 25% of the White PLA went through that process. If we calculate the cost of this massive hull, it comes to close to $45, for a 1.25 meter long hull. This technology, obviously, allows the realization of models at a low cost. I have started sanding very lightly the various sections and drilled the portholes. It is a lot easier to work on one section at a time, rather than on the entire hull. It is now time to assemble that behemoth. To glue the PLA, I am planning to use the special soldering cement available under the names of Plastruct or more economically the MEK (Methyl Ethyl Ketone), available at certain hardware stores or online for a fraction of the cost of these Hobby Shops little bottles. A Plastruct bottle is about $7 for an ounce, whereas I can get half a litter for less than $20, including shipping. The old Ambroid bottle has been refilled with the pure MEK. Same consistency, same smell, same gluing power. Yves

Lovely model and great story about the name of the town/boat. Yves

That is so funny.... I was looking at the Micro-Mark catalog yesterday and came to the page where that kit is described. I was wondering, who could have fun building a Hearse Wagon with the miniature coffin inside from 1895.... The answer came today !!!! Kevin !!! LOL Yves

This water is gorgeous and renders so well the cold and ominous fjords of Norway. Yves

Superb model. Congratulations. Yves

Beautiful collection. That trawler is enormous. Yves

That is a very tall mast. Beautiful ! Yves

Quick update: printing of the hull couplers (8 of them) is done. Each took between 1:30 and 5:00 hours to go.... I am currently printing the pedestal (2 x 7 hours) and still have four major pieces of the hull to go through: another week of non-stop printing. With Virtual kit, you either need multiple printers or build two kits at the same time... :-) Yves

Superb model. The P-38 is truly a special bird. Yves

Craig, I am buying the PLA filament from Amazon. The brand is Overture and each spool cost about $19 to $23 depending of the color. Spool comes with 2.2 pounds of filament, which gives you a lot to print. I have been able to do 4 sections of the hull, plus extra parts with less than one spool. I suspect that your plane will not take more than 1 spool. Only drawback of this technology: the material is incredibly hard..... not easy to sand or drill. Printing may not be that expensive, if you are not in a hurry. They may schedule you during the night and give you a nice price. Yves

Time consuming progress..... 28 hours.... Hull_2 section: Even better....33 hours !! Hull_7 section: The positive side of these virtual kits, is that while the model is building itself, you can get a life !!! Yves

Finally, someone will cover that MONUMENTAL kit from Trumpeter. I have been waiting for this moment, a long time. Thank you so much Winnie for launching this massive endeavor. We will all enjoy it immensely. For information, there is a very active Forum on the Titanic, in French (not sure if you can decipher it or not), but it has a lot of information and these guys are searching around the world for after-market parts to make the model even better than it is: https://www.laroyale-modelisme.net/f32-montages-titanic-sisterships and this one in particular: https://www.laroyale-modelisme.net/t25181-montage-titanic-trumpeter-1-200-par-le-barbenchon Yves