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roma847

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About roma847

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  1. Hello everybody, but first I've continued with the LH2 Cable Tray and the associated tiny parts of the transition, which are all in the millimeter range and thus extremely tricky to handle, what only is feasible under the Headset magnifying glass. In the process, I carefully approached from all sides using my file set and my finest mini-saw (0,1 mm), whereby one must keep an eye on the required dimensions, which is for this bow 1,5 mm x 1,5 mm, which is why one has to measure again and again. And since I prefer to work with a little bit of excess, a post-processing is still necessary, which becomes particularly tricky once the part has been sawn off. As a result, an undersize can quickly arise, which is not so good. So, choosing the Rectangle profile of 1,5 mm x 3,2 mm was not exactly brilliant and has unnecessarily complicated the whole procedure. That's why I used a Square profile 1,5 mm x 1,5 mm in the second attempt, which was much "easier" to handle, since the outer dimensions are already fit, and what I could have done better immediately. At first I filed the rounding and then sawed off the length of 1,5 mm. However, care should be taken during the following processing of this mini-piece, whereby I held it for filing the inner rounding with my Precision file (Ø 1 mm) in a Cross tweezer and at the same time supported it from below with the finger. And since the test fitting of the bow on the Cable Tray looked good, I then glued the bow carefully, and something aligned yet, which resulted in a good fit of the bow. Then I've cut the Middle plate (part 3) out of a Rectangular profile 1,0 mm x 1,5 mm x 2 mm, and glued it onto the bow. And after the successful fitting I was able to catch my breath, because this transition fits quite well and there is still enough space for the oblique transition to the Umbilical plate (parts 4/5). And with this intermediate result I can be quite happy.
  2. Thanks Mark for your nice compliment. Hello everybody, in the meantime, I've attached this Cable connection between the Vertical strut and the Distribution box, for which I've glued two tiny pieces of Evergreen Strip which are barely noticeable. And now to the other end of this Cable Tray in the red circle, which after the arc at the end firstly goes down and then immediately runs rearward in a short 90° arc underneath the Crossbeam. Source: NASA This course can be followed in the following photos. Source: NASA Source: georgesrockets.com (George Gassaway) Source: capcomespace.net In this drawing, the course of the two Cable trays is simplified depicted, but what is helpful for scratch-building. Source: System Definition Handbook SLWT, Vol. I (Lockheed Martin) Behind the crossbeam follows at the end of the cable tray the angled transition of the parts with TPS Cladding (2, 3, 4, 5) up to the Umbilical Plate under the orbiter, which seems to be difficult to scratch due to the minimal dimensions of the parts, especially since the clear height between the Cable Tray and the Umbilical Plate is only 3 mm, from what the height of the CT transition to 4 mm results, which should become quite tricky. Source: georgesrockets.com (George Gassaway) Afterwards I've tried the arc of the Cable Tray on the front of the Crossbeam with the help of my Balsa & Bending technique. During mounting one has to make sure that the Cable Tray is not directly in contact underneath the Crossbeam but sits on a small spacer (0,4 mm) which is already glued here. As the test mounting shows, however, from the arc would leave almost nothing left, which would probably complicate a flush connection. Therefore, it will probably be better if the cable tray is first glued to the front with a bit of supernatant, after which a matching strip is glued in the interspace which then is rounded. And this construction I've tested provisionally with tape, and was surprised that the clear height between the Cable tray (0,6 mm x 1 mm) and the Umbilical plate is actually 3 mm and thus is perfectly in accordance with my previous estimates of the measurements. And this is a first attempt to make the TPS arc (part 2) from a rectangular profile 1,5 mm x 3,2 mm, whereby I am looking forward to the result.
  3. Hello everybody, as one can see in this photo, the TPS Cladding of the Vertical Strut is reaching still a bit more upwards, has a few steps there and looks thus a little bit different than the Newware-Resin-Cladding. Source: forum.nasaspaceflight.com (DaveS) In order to enable the connection to the Distribution box of the LH2Cable Tray based on the original, I have tried to recreate these details and have glued tiny particles of the narrowest and thinnest Evergreen strips around the strut, what was again a delicate fidding, whereby the transitions still need to be slightly sanded. Then I've fixed the paper template of the LH2 Cable Tray with the Distribution box on the Crossbeam again to see whether or how this matches with the clearances, and whether there is still enough space for this box, which could be about right, as one can see here. Then I've transferred this template onto a 0,5 mm Styrene sheet and cut it out piecewise, for which I used my finest Mini-saw (0,1 mm) for the long cuts and for the short cuts my Chisel cutter. And after that long cut, the part has been finally exposed, and was then finely smoothened at the edges. The following test fitting of the Cable Tray at the Crossbeam looked quite well, so that I could turn to the small Distribution box for which I've used an Evergreen square profile 1,5 mm x 2 mm, which, however, was difficult to handle. As the test fitting of the Cable tray with the glued box shows, the seat is quite neat, so that only the sloping bottom side would be something to straighten. Then only the cable connection would have to be attached, after which it could then continue on the other side.
  4. Hello everybody, in order to be able to scratch-build the LH2 Cable Tray as completely as possible, which I'm intending, I first had to clarify its continuous course, which lasted long enough. And this course can be subdivided into two parts. The first and much longer, but simpler part extends over the entire LH2 Tank, starting behind the Intertank, and then flows into the right Vertical Strut at its top end (see yellow circle). For the moment, however, I will defer this part until later, because it has to go along with the laying of the Ice Frost Ramps of the GH2/GO2 Press. Lines, what will follow later. Source: forum.nasaspaceflight.com (DDG40) In this strut, the cables then run upwards and enter the gray "Distribution box" from behind, Source: forum.nasaspaceflight.com (DaveS) and from there the cable tray runs on the front side of the Crossbeam to the other side, which I will show in more detail. Source: Scott Phillips And now follows the difficult and time-consuming part of every scratch exercise, in which I always have to determine the required dimensions of the individual parts by using suitable reference photos/drawings. One is spoiled for choice, depending on which reference measure (yellow) one refers, either to parts of the original photos, or to those of the Airfix Kit, which then sometimes can lead to a compromise between the two possibilities, so to speak on something between. In the following photo, the transition from the "Distribution box" to the following Cable Tray is unfortunately covered, which is why I had to determine it by appropriate cutting lines to be able to estimate its dimensions. The dimensions of the "Distribution box" can indeed be determined well from the next image, but here the transition area to the cable tray is covered, which is why no clear reference dimension can be found. That's why in anticipation of the next photos I used the height of the Cable Tray (2,7 mm) as reference measurement. This is the already oftener shown photo by DaveS, Source: forum.nasaspaceflight.com (DaveS) on which one can see in a rotated and greatly enlarged representation of the transition of the LH2 Cable Tray from the vertical strut into the "Distribution box" very clearly, whereby the oblique perspective allows no accurate measurement of the parts. But there is this photo by George Gassaway, Source: georgesrockets.com (George Gassaway) which, in rotated and enlarged view, allows some important estimates due to the almost direct view, as well as the height of the Cable Tray (2,7 mm), previously chosen as a reference measurement, which in turn was determined from the diameter of the Thrust Strut of the Airfix Kit (Ø 3,2mm). And so the LH2 Cable Tray arrives on the other side of the Crossbeam, whereby here one also can see well the TPS cladding of the GH2 Press. Line. And from there it is only a short distance to the LH2 Umbilical Plate, into which both the Cable Tray and the Press. Line are inserted from the bottom, wherewith we finally arrived at our destination. Source: georgesrockets.com (George Gassaway) Source: capcomespace.net And so now for the practical implementation, wherefor which I have used this drawing from the ET Bible. Source: System Definition Handbook SLWT, Vol. II (Lockheed Martin) Into this drawing, I have drawn as a reference measurement the distance between the two support points of the Airfix orbiter (32 mm) and then reduced the drawing to 1:144 and also still mirrored. And with this I have now tried to draw a true to scale template for the Cable Tray with the appendage of the "Distribution box" and print out, which I also managed to some extent. But what looked just so nice and catchy on the photos yet, shrinks on a scale of 1:144 after the expression again together in such a way, so I had to look twice when cutting out the Cable Tray. And that's what the part looks like on the Airfix Crossbeam, which I now only need to transfer to 0,5 mm Styrene sheet and carefully to cut it out. On the right side of the Cable Tray one has to add this rounding and, if possible, also the 90° bend to the front, which one can see well in the zoom on this photo of the ET-121. Source: NASA And for completion, all that is still missing is the TPS cladding of the GH2 Press. Line, which will be made later.
  5. Thanks Mark for looking in on me again. Even if these are only small steps, it goes ahead ...
  6. Hello friends, I've now chosen to glue the LO2 Feedline Brackets, for which I've now also used 1 mm Styrene, so that the strengths of the brackets on both sides are the same. However, I've only glued the brackets to the Crossbeam, and not to the Feedline, because I still have to glue the rings next to the Feedline supports, as well as the front missing support behind the Intertank, for what I need enough freedom of action. The positioning and gluing of the tiny brackets was quite tricky, but then I've managed it quite well. And the Diagonal Cross Strut fits in between quite well too. Then I've still glued the Resin-TPS-Claddings to the Vertical Struts, so they will not be lost. And now it can go on with the LH2 Cable Tray on the crossbeam.
  7. Hello everybody, but as I mean by this time, these recesses in the upper rings seem to be filled up conclusively with the appropriate TPS material, which is why it is unnecessary. Furthermore the Support Brackets for the LH2 Feedline also look different and are also mounted differently than the brackets for the LO2 Feedline on the right side. Source: NASA As can be seen from this image, the two LH2 Brackets are not rigidly connected to the crossbeam like the LO2 Brackets, but rather are slightly laterally movable by Hinge elements, which is said to allow unrestricted relative distortion between the rear ET and the orbiter. Source: NASA More precise information about the shape of the outer LH2 Bracket is given by this drawing, from which I have also determined the dimensions, whereby I've used the width of the Airfix Crossbeam (2,7 mm) as reference measure. Source: System Definition Handbook SLWT, Vol. II (Lockheed Martin) However, one has to keep in mind that this is the SLWT Handbook, i.e. this is how the Super Lightweight Tank (SLWT) looked like, which was used starting at the end of 1998, with some modifications in order to reduce weight in favor of larger payloads, compared to the Lightweight Tank (LWT) used for the first time at STS-6 (ET-8). And as a further closer look at just this ET-8 shows, the inner bracket looks a bit different than my previous one, Source: forum.nasaspaceflight.com (Jester) which is why I've modified it a bit (right). In order to finally fix the brackets and bond them with the Crossbeam, I put the Orbiter back on and fixed it with tape to see the exact distances and to adjust the brackets accordingly. And in this position, the inner bracket was glued by using MEK with the Crossbeam and the LH2 Feedline. And now to the preparation of the outer bracket, which is drawn slightly longer, to which later the two holders for the LH2 Cable Tray are glued, as can be seen from the drawing. The front cable tray mount is nice to see in this photo, but whereby the two Umbilical photos in the capcomespace dossier are reversed unfortunately. Source: capcomespace.net This was followed by the fitting of the outer bracket, and their cutback to the right length, and finally their gluing with the crossbeam and the feedline with MEK. Then I was able to remove the orbiter again and scrutinize from all sides the LH2 Feedline, glued on the crossbeam. And now I could either glue the LO2 Feedline Brackets or lay the LH2 Cable Tray on the front of the Crossbeam.
  8. Thanks Kirk for your well-meant inspiration, but as you said yourself, these parts are so small that one can barely handle them. But you've egged me on a little bit, so I'll try to apply the little cutouts in this upper ring by using my smallest round file, wich is only 0,5 mm at the top. And I think that should work, keep your fingers crossed! BTW, above one can see one of the two tiny LH2 Feedline Brackets.
  9. Hello friends, after I've taken a look at the LH2 Feedline again and comparing it with my Reference photos, Source: georgesrockets.com (George Gassaway) Source: NASA I have decided to remove the rings that are too narrow (0,5 mm) and to replace them with wider ones (1 mm), which are much better corresponding to the original. No sooner said than done! But when I measured the stub then after grinding off the rings, its diameter was instead of 3 mm only 2,7 mm, which I did not like. That's why I took a rod Ø 3 mm and bent it under hot air according to my proven Balsa-Bending-Technique. But as it is sometimes, if one has not bent anything for a long time, this bending process did not go satisfactorily, because the lower balsa support behind the kink was too short, so that the kink of the rod was not bent exactly enough, but was slightly rounded as one will see. I have taken this into account by a longer slope of the support and a more stable clamping of the rod, which has resulted in a more accurate bend, what one can see in the following picture by comparing the two bended rods. Above it are already to see the 1 mm wide rings, which I have cut off from a tube with Ø 4 mm, which I have previously drilled out to 3 mm. Then I have filed the new stub to the required length and drilled a hole for the guide pin (Ø 1,2 mm), and glued it in place. Here the two rings have been pushed onto the Feedline, which I will glue with MEK. And so the new LH2 Feedline looks like after fitting, which I like much better now. And now I could also adjust the Feedline Brackets, which sit directly above the upper ring. But if one looks closely, one can still see a further ring directly below the Umbilical Plate. Source: forum.nasaspaceflight.com (DaveS) And this ring I have now also housed yet, as one can see in these two pictures, wherewith I now let it be good. The odd little cutouts in this ring I prefer to avoid because the ring might not be able to bear it.
  10. Hello everybody, today, I've been dealing with some filing and sanding work, first I had to sand the Vertical Strut of the ET/Orbiter Attachment on the LH2 side for the TPS cladding of the Newware Kit and had to modify the Resin part still a little bit. And then there was also the associated Longeron, which had to be modified too. Since the outer LO2Feedline Support Bracket was missing anyway and the inner did not quite fit and was a bit too small, I've scratched both Support Brackets new. It should be noted, however, that both brackets look similar, but have not the same shape. The inner bracket is a bit lower, because the Diagonal Cross Strut runs over it and needs the appropriate space, as onecan see on this image. Source: NASA Afterwards I've sanded off the two unnecessary wide rings at the end of the Feedline. As one can see here, I have to smooth the line around the stub yet, which has to be removed anyway after the tests and its hole must be filled too, because in reality there were neither the two rings nor this holder. Last night I did not notice the nicks, but even all the more so in daylight. These are the modified parts, whose seat on the ET I've tried next. And as one can see, they fit quite well so far. Now I'm going to modify the too short LH2 Feedline Support Brackets, and then it goes on with the tricky Cable Trays with all due respect. But scaremongering does not apply!
  11. Thanks Thom for looking in on me, yeah, small and tricky details, that has always been my passion, it's like a drug, I can't let go ...
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