roma847 Posted February 6, 2018 Author Share Posted February 6, 2018 Thanks Rich, sorry, but unfortunately I'm no local hero. Hello everybody, and even after a day, the strips are still gluing unchangedly in place, so that the decision for the Bare-Metal Foil (New Improved Chrome) has fallen. Then I wanted to see how the stripes on the ASTC would look like, and was pleasantly surprised again. Cutting these approx. 7 mm long and 1 mm wide strips and gluing over the dividing lines between the segments, however, proved to be the expected delicate matter, because one has hellishly to take care when handling with cutter and/or tweezers, so that the very thin foil does not tear off. And as one can see, the dividing lines under the stripes are becoming slightly visible, but the same can also be seen on this photo from the STS-43 at a higher magnification. Source: flickr.com (NASA on The Commons) All in all, a completely successful matter with these 3D-ASTCs, which was worth all the effort. 2 Link to comment Share on other sites More sharing options...
roma847 Posted February 6, 2018 Author Share Posted February 6, 2018 Hello friends, and also after two days, the state of the Bare-Metal Foil stripes is unchanged stable, and looks very well. 3 1 Link to comment Share on other sites More sharing options...
Mustermark Posted February 8, 2018 Share Posted February 8, 2018 This is looking great. I have just ordered a pair from Shapeways to put with my shuttle kit for a ‘rainy day’. Link to comment Share on other sites More sharing options...
roma847 Posted February 8, 2018 Author Share Posted February 8, 2018 Hi Mark, which kind of AFTCs have you ordered, FUD or FXD? Link to comment Share on other sites More sharing options...
roma847 Posted February 8, 2018 Author Share Posted February 8, 2018 Hello everybody, after having been more intensively involved with the AFTC rings that have been printed meanwhile by Shapeways and tested by me, I want to go back to the 3D modeling of the Intertank wherewith Michael Key had started last December, what I've been posting about. Therefor I had sent him in the result of my research my drawing and the estimated Stringer dimensions without and with foam insulation, where actually only the dimensions with foam insulation for his 3D modeling are relevant. Thereupon he had to adjust his 3D model once again, which I as a 3D rookie have not imaginated so complicated, but which should turn out to be a fallacy. At the beginning of the year he told me that he has meanwhile modeled another version with these stringer dimensions, given by me, Source: shapeways.com/forum (Michael Key) consisting of each 26 Stringers in the two Thrust Panels and of each 40 Stringers in the intervening Stringer Panels. But somehow I immediately stumbled over his number of 40, that's totally 80 stringers in the Stringer panels, which I was very surprised because I dimly remembered a number 108 in our German Raumcon discussions, wherewith the confusion around numbers and terms started at the beginning of my project start (11/2011). After intensive researches I finally found the explanation in the System Definition Handbook SLWT, in which the Intertank structure is described quite well. Source: Space Shuttle/External Tank System Definition Handbook SLWT After that one has to distinguish the following terms: While in the six Skin/Stringer Panels (45°) there are each 18 of these Stringers, one speaks in the two Thrust Panels of Ribs, whereby in each case 26 parallel ribs as well as seven circumferential ribs are integrated in these panels, Therewith was clarified at least the number of stringers, namely 108, which showed that Michael Key's 3D model had with totally only 80 too little stringers. And now I had to explaine this fact heavy-heartedly Michael Key, whereby I was afraid that he would lynch me for it. Thereupon he was very disappointed and had initially thrown in the towel quite frustrated. But of course, I did not want to give up that fast ... On the other hand, it would probably have been more useful to distribute the Stringer number onto the circumference of the eight 45° panels, whose drawing he had also been given by me. But in hindsight one is always smarter than before ... In the meantime, I did it my way both for the six Stringer Panels and for the two Thrust Panels with following results and sent it to him, in the hope that he would have an insight as well as a good will. Long story short, therewith I obviously had affected his honor, so that he was ready to go on. But I had to confirm to him that it would finally remain, in each case 54 stringers in the Stringer panels (135°) and in each case 26 ribs in the two Thrust panels (45°), whereupon I gave him my word and was jolly glad. 3 Link to comment Share on other sites More sharing options...
Mustermark Posted February 9, 2018 Share Posted February 9, 2018 Diplomacy is one more skill you can demonstrate in this endeavour! Hopefully Michael Key will make the final version available to all via Shapeways... and we can thank you both. Again, it is due to your meticulous research. 1 Link to comment Share on other sites More sharing options...
Biglad82 Posted February 9, 2018 Share Posted February 9, 2018 Outstanding work Link to comment Share on other sites More sharing options...
roma847 Posted February 9, 2018 Author Share Posted February 9, 2018 Thanks Mark and Biglad82, yep, Michael Key's 3D Intertank (1/144) will be available at Shapeways for everyone of course, when it will be finished. Link to comment Share on other sites More sharing options...
PZRGREN Posted February 10, 2018 Share Posted February 10, 2018 Finally catching up on your build Manfred, outstanding and such a joy to witness. Regards, Roger. Link to comment Share on other sites More sharing options...
John_W Posted February 10, 2018 Share Posted February 10, 2018 So, where does the sports car go? 1 1 Link to comment Share on other sites More sharing options...
roma847 Posted February 11, 2018 Author Share Posted February 11, 2018 Thanks guys for your nice compliments. Hello everybody, there are progresses to be reported of Michael Key's intertank modeling. After the number of Stringers (108) and that of the Ribs (52) have been clarified, we now have to clarify some further details on the Intertank, which are marked in this image, some of which have already been integrated into Michael's model. Source: NASA Here are his latest 3D pictures, whereby I wondered at first about these six plates in the Access Door, that I've never seen before. Furthermore, I noticed that the size and location of the Access Door (AD) and the Carrier Plate (CP) cannot be quite right, Source: shapeways.com/forum (Michael Key) which is why I determined them more precisely based on photos, wherefore I used the agreed reference size 1 Stringer+Valley = 1,3 mm. At first I used this great direct view of the Carrier Plate, which has almost no perspective distortions, what should be considered. For the determination and conversion of the measures, the following explanation of my numbers in the photos with and without mm is necessary, so that one does not get confused. Numbers without mm are measured values in the respective photo, and Numbers with mm are the converted measurements in 1/144. And if one compares this photo with his model, stands out that the distance D2 of the Carrier Plate from the Thrust Panel is too large because it should be only 2 Stringer+Valley (2,6 mm). Source: NASA With this distance and the determined dimensions of the Carrier Plate of 3.5 mm x 5.0 mm (W x H) I am afterwards in this photo of the Access Door boarded, which unfortunately is not so distortion-free in the area of the door. And in this photo one can see that the door is flat and has no attached panels. Source: NASA Here's a similar picture at which the access door panel is removed, which is attached with 44 flat profile screws. Source: NASA Thus, the Access Door and the Carrier Plate would have the following dimensions: Access Door: 9,1 mm x 7,7 mm (W x H) Carrier Plate: 3,5 mm x 5,0 mm (W x H) As one can see in the following image, the Fairings of the LO2 Feedline (17'') and of the GH2 Press. Line (2'') were added, as well as the LH2 PAL Ramp and the LO2 PAL Ramp, as well as the Supports for the two Press. Lines and the associated Cable Trays. Thereto Michael has suggested to omit the two thin Press. Lines and the Cable Trays, as they would go beyond the intertank anyway and could possibly break off during printing or transport. He was worried about the PAL Ramps. While the LO2 PAL Ramp could survive at the top, he fears that the LH2 PAL Ramp could probably break because it's very long and thin. So he asked if he should cut them off at the ends of the Intertank, which I agree with. Since I anyway want to insert the LO2 Feedline and the Press, he should omit them away, but not the Cable Trays, because I could continue them to the front and backwards. Then I still showed him these two photos, on which one can see that the bottom plates of the Fairings are flush with the stringers and not put onto, what he has accepted and wants to change. Source: NASA Source: NASA These were essentially my hints and correction wishes. Regarding of his plates attached on the Access Door, which I had queried, he sent me this photo here, which surprised me, since I did not have seen it yet. That's why I asked him if he had any source, whereby it could possibly be a Mock-up. I believe that shows once again that a timely and consensual coordination of such details is important for a smooth process, that's why one never stops learning. 3 Link to comment Share on other sites More sharing options...
Caerbannog Posted February 11, 2018 Share Posted February 11, 2018 Really amazing work and research. Gobsmacked again... René Link to comment Share on other sites More sharing options...
roma847 Posted February 11, 2018 Author Share Posted February 11, 2018 Thanks René for your nice words. Hello everybody, let's go step by step on our way to the goal, here are the next images of Michael Key's 3D modeling. As one can see in this image, he has omitted both the six plates in the door and adjusted their size, as well as he had corrected the distances of the AD and the CP from each other and from the Thrust Panel. Source: shapeways.com/forum (Michael Key) The position of the CP, however, remained unchanged and still sits too high up, although I had already marked it in this last image, Source: NASA what one can also see in this photo. Source: forum.nasaspaceflight.com (Jester) Furthermore, it is noticeable that the bottom plate of the large LO2 Fairing admittedly is flush with the stringers, but not that of the small LH2 Fairing, Source: shapeways.com/forum (Michael Key) which is still to be corrected, according to the following photo, but hopefully will not cause any problems. Source: NASA Then here are two more images of the small supports of the GH2/GO2 Press. Lines (2''), first with the indicated lines, Source: shapeways.com/forum (Michael Key) and here the final design without the lines, whereby the thin wires (Ø 0.3 mm) will separately be inserted later and covered with small caps. Source: shapeways.com/forum (Michael Key) Now I hope that these last changes can also be considered by him, according to which an upload of the 3D model to Shapeways nothing would stand in the way. But Michael Key wanted to be honest and told me, that there are some very small parts in this model that could possibly overstrain Shapeways' possibilities, so the model might not pass their inspections the first time around. That would be normal, and Shapeways would let him know the problem, which he would correct. That's why I'm very curious, but initially his modified model is still due. 1 Link to comment Share on other sites More sharing options...
xffw45343tg Posted February 11, 2018 Share Posted February 11, 2018 Just an idea: Rather than chop of the trunking entirely leaving a butt joint, why not leave a short stub with a step ("lap joint") in it, so that separate pieces placed on the tanks could locate into this? I suspect the parts are so tiny that it would give no advantage - but like I said, just an idea. Kirk 1 Link to comment Share on other sites More sharing options...
Mustermark Posted February 12, 2018 Share Posted February 12, 2018 Meticulous and perfectionist as ever... Michael Key will need to be patient and also perfectionist in this amazing collaboration. I await the good result with Paypal at the ready! Link to comment Share on other sites More sharing options...
roma847 Posted February 12, 2018 Author Share Posted February 12, 2018 Thanks guys for your nice words, but we have still to wait a little bit. Hello everybody, once again to this photo of the Access Door, that was shown by Michael Key, whose source was previously unknown. A friend from the ARC Forum (southwestforests) has found the same photo in this Article, that was published by Jacques van Oene. Source: spaceflightinsider.com (Jacques van Oene) By the end of 2012, this Original Test-ET (1977-80) had been exhibited on the KSC-Visitor Complex, but 2013 had to give place for the new Atlantis Exhibition Hall, in front of whose entrance since then there is standing a huge Mock-up ET with boosters. And in this Article I found many other interesting photos of this ET, including also this photo of the Carrier Plate, which is just five stringers above the Access Door, as we now know. 1 Link to comment Share on other sites More sharing options...
roma847 Posted February 15, 2018 Author Share Posted February 15, 2018 Hello everybody, and now back to the 3D Intertank, where Michael Key is coming down the stretch after his considering of my last little changes. And just now, my "special" friend and helper DaveS in the NSF Forum comes out of the wood and presents me this interesting photo of the Access Door at STS-31 (1990), unfortunately without source. But after I've found the image in Google, I recognized it from the URL, according to which it comes from the collection of George Gassaway, which I know by now. Source: georgesrockets.com (George Gassaway) And since I found a similar photo of the STS-30 (1989), I suspect that since the use of the Leightweight Tanks (LWT), starting at STS-6, such doors were installed, which apparently also had a foam insulation. Source: georgesrockets.com (George Gassaway) For this also militates this photo of my friend James MacLaren, which also shows such a door in the background. The image shows the Challenger on Pad 39-B, probably during the preparation for her fateful final mission STS-51L (1986), what I still will find out. Source: forum.nasaspaceflight.com (James MacLaren) Consequently the photo used so far for the 3D modeling shows a Graphite-Composite door, as has been used later on the Super Lightweight Tanks (SLWT), Source: NASA like here at the STS-133 (2011). Source: NASA For Michael Key's 3D-Modeling this realization is coming too late unfortunately, but which is not a problem, because I can glue this door with the two handles later on, especially since it is very small (9 mm x 8 mm), as one can see here. 1 Link to comment Share on other sites More sharing options...
roma847 Posted February 26, 2018 Author Share Posted February 26, 2018 Hello everyone, now it goes on with the 3D Intertank journey, which went into the next round, which keeps me in suspense. Unfortunately I have yet overlooked an important detail that was not yet correct in the last pictures of Michael Key's 3D model and consequently could not remain, what was to be seen 14 days ago in this picture. Source: shapeways.com/forum (Michael Key) I had circled the part already, but at first I was only interested in the bottom plates of the two Fairings. After I had Michael Key pointed this and had been once more showing the still too high Carrier Plate, he wanted to get back to with the final model for the final checkup, for what I specifically had asked him befor a possible upload to Shapeways . Almost at the same time DaveS came up with this, so far unknown Access Door, how it most likely had looked like at ET-8 during STS-6. Source: georgesrockets.com (George Gassaway) About this I have informed Michael Key and told him at the same time that he should not change the door, because I could scratch this little detail as well. After that he surprised me with his final Intertank version, in which he had even considered this door in addition to the lower located Carrier Plate, which of course I was pleased. Source: shapeways.com/forum (Michael Key) And here are further pictures of his 3D model: After I have begun to wonder about the arrangement of the two Fairings as well as the PAL Ramps and Cable Trays at this close-up my hair suddenly stood on end. Apart from the somewhat too crude shape of the big LO2 Fairing, both fairings are next to each other almost at one height, but what is not true, although in turn was clearly visible on previous photos, but what apparently he has not registered and consequently not so implemented. In reality, the arrangement of the fairings however looks like as at these two photos. Quelle: NASA Source: NASA But the bafflement was following, by telling me at the same time that he had uploaded his model to Shapeways, which would have allowed everybody to order immediately, but what was agreed otherwise, by the way, for EUR 58 (WSF) or EUR 91 (FUD), but with these errors. And in the 3D panorama view of the Intertank in his Shapeways Shop, this error was also clearly visible (see red dashed line). Furthermore, I wondered about the tapering shape till the top of the two PAL Ramps and the resulting gap to the Cable Trays, which is not true. Source: shapeways.com (The Aerospace Place) Then I have immediately communicated Michael Key this change requirement on the basis of these earlier photos, Source: NASA Source: NASA what I have marked on this image again. Source: shapeways.com (The Aerospace Place) Because of these mistakes, I have asked him to remove his offer from his shop site immediately, which he then has done. A controversial point is still the form of the fairings and the arrangement of the GH2/GO2 Press. Lines, for which he has sent me this picture, in which I have marked my changes in red. Source: shapeways.com/forum (Michael Key) And as one can see in these photos, the two Press. Lines should run closer to the LO2 Feedline . Source: NASA Source: georgesrockets.com (George Gassaway) As far as the current state. Slowly but surely, but somehow we'll crack the hard nut like the squirrel. 2 Link to comment Share on other sites More sharing options...
roma847 Posted February 26, 2018 Author Share Posted February 26, 2018 Hello everybody, the Intertank in Michael Key's Shapeways Shop currently looks like this, but still with the important note Not For Sale, what will hopefully change soon. Source: shapeways.com (The Aerospace Place) While everything looks awesome on this side, there are a few detail problems to solve on the other side. But we can do it together, in any case I have supplied the necessary reference ammunition. 1 Link to comment Share on other sites More sharing options...
roma847 Posted February 28, 2018 Author Share Posted February 28, 2018 Hello everybody, Michael Key has still modified the shape of the two Fairings a bit, which looks really better now. Source: shapeways.com/forum (Michael Key) And the arrangement of the details now agrees fairly well with the original and can therefore remain so. Source: NASA And since the wall thickness of the LO2 Fairing is only 0,25 mm in 1:144, we have agreed on to insert no opening for the LO2 Feedline (Ø 3mm), so I can glue the line directly. With that Michael Key has now reached the home stretch and the final is heralded. 1 Link to comment Share on other sites More sharing options...
roma847 Posted February 28, 2018 Author Share Posted February 28, 2018 Hello everybody, so friends, we are just before completion. At first still this small addendum, which I have reached out non-binding to Michael Key, without knowing whether he would go into rapture in view of my previous special requests. But I thought, asking does not cost anything, either-or? On this image of the STS-6 one can see these two areas, in which the Stringer-Valleys are filled up with Insulating foam, which would perfectly complete the already nicely detailed Intertank. Source: retrospaceimages.com (J. L. Pickering) The white part (left) is the RSS Antenna, as well as an Aerodynamic Vent in the middle of the right-hand area, as I found it in George Gassaway's ET collection, here at STS-37 (ET-37), Source: georgesrockets.com as well as here at STS-36 (ET-33). Source: georgesrockets.com And what should I tell you, in his final version, he has even implemented these two details. Source: shapeways.com/forum (Michael Key) Source: shapeways.com/forum (Michael Key) This surprise he really succeeded. Link to comment Share on other sites More sharing options...
xffw45343tg Posted February 28, 2018 Share Posted February 28, 2018 Hi Manfred, These last few posts really make you think about the future of this hobby. It used to be that "aftermarket" resin replacement parts could be of variable quality and fit - to the extent that they are sometimes not worth the bother. With the advent of printing on demand from a +/-0.05mm (or thereabouts?) resolution process, the accuracy is now almost limited by what the draftsperson is able to see (or be made aware of by people such as yourself). It is actually very exciting - there is a prospect of models becoming more and more realistic, and scale being a thing that you select at ordering time. 1:32 Shuttle/Launch pad anyone? Kirk Link to comment Share on other sites More sharing options...
roma847 Posted February 28, 2018 Author Share Posted February 28, 2018 Hi Kirk, and thanks for your nice thoughts, which provide a broad scope for speculation and interesting new ideas ... But I would be satisfied already if Shapeways were able to realize a resolution of the stringers and ribs in the range of approx. 0,3 mm in good quality. Link to comment Share on other sites More sharing options...
roma847 Posted February 28, 2018 Author Share Posted February 28, 2018 Hello everybody, after the events have almost happened in quick succession today, it is now done. But always nice in turn step by step. After Michael Key had uploaded his model to Shapeways, he sent me the Link, from which the following images are taken, which are showing the awesome Intertank in different views, as one can see. Based on the large number of pictures you can already see how much the end product thrilled me ... Thereupon I immediately ordered a print for 95,99 EUR incl. shipping. In the midst of the delirium of joy then came a friend from our Raumcon Forum with his damper regarding the shrinkage problems at FUD and FXD, as well as in connection with the costly stiffening rings, which one would have to consider. Based on these legitimate hints, Michael Key responded immediately and after a few changes has uploaded his model again, and now lets print it 0,8% larger. He also pointed out that one possibly might have to sand a bit, either on the printed Intertank or on the ET parts of the kit, but that would not be unusual and should be feasible. However, as this model, with a wall thickness of about 0,7 mm, is quite thin, he would not recommend removing the stiffening rings. Instead, he has reduced their mass by enlarging the holes in the middle, which has fortunately resulted in a cost savings of about 20 EUR, that one can not complain about. And those changes looked like this. Thereupon I immediately have canceled my first order and reordered new, and here is the current Link, over which one now can order the Airfix Intertank (1:144) for 71,83 EUR in FUD, and in the 3D view (top right) one can keep a close eye on it from all sides. Source: shapeways.com (The Aerospace Place) Now I hope that Shapeways can also print the part with all its details, wherefore all available thumbs are needed, to make it to a round matter in the end in the truest sense of the word. Link to comment Share on other sites More sharing options...
roma847 Posted March 2, 2018 Author Share Posted March 2, 2018 Hello everybody, my next project will be the Ice/Frost Ramps on the LH2 External Tank, and I hope that Michael Key can help me with this as well. Source: NASA And so the ramps for the GO2/GH2 Press. Lines look like in detail. Source: NASA I know that my friend Bill (niParts) has modeled a set of these Ice ramps in 1:72, but in 1:144 they are unfortunately much smaller. Source: shapeways.com (niParts) In reality these ramps are 2' x 2' x 1' , that means 2 mm x 2 mm x 1 mm for the ET (1:144). The diameter of the LH2/GH2 Press. Lines is 2'' = Ø 0,35 mm (1:144) and should be the reference. The openings in the ramps are slightly larger, approx. Ø 0.5 mm, as one can see in this image. Maybe that these very thin wall thicknesses could be a problem for Shapeways 3D printer? 1 Link to comment Share on other sites More sharing options...
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