spaceman Posted March 21, 2020 Author Share Posted March 21, 2020 (edited) Hello friends, now that my new PC is running, it can finally continue on the Stack-construction site, whereby it specifically concerns the front connection points between the ET and the SRBs, these are the so-called ET/SRB Forward Attach Fittings, one of which was already shown in this picture, whereby the cladding over this green segment is missing. Source: NASA Apparently, this is not just a cladding, because as one can see in this photo of the STS-6 Stack in the final state before the launch of the Challenger, there are two white boxes stacked over one another. Since this image shows the front of the stack facing the orbiter, the question immediately arises as to how this connection assembly may have looked on the back. Source: forum.nasaspaceflight.com (woods170) To find out, I had to do a bit more research and have found this photo of the ET-121 after its separation from the Discovery (STS-114), that was the so-called Return To Flight Mission after the Columbia disaster (STS-107). On that one can see on the underside, although a little small, the part of the fitting that belongs to the ET. The rest of the part is therefore on the previously blown away Booster. Source: NASA The following photo montage shows how the two assemblies of the attachment fit together. Helpful for my understanding were these drawings of the Attach Fitting, on which the parts belonging to the ET are colored green and those of the SRB are blue, which are connected by the Separation Bolt. Source: System Definition Handbook SLWT, Vol. I (Lockheed Martin) Final clarity about the arrangement of the fitting on the front I then got through these two photos, in the left image in opened State without cladding (RSS Fairing) and in the right with the gray cladding, Source: NASA Source: spaceflight.nasa.gov which I then compared directly in this photo montage. Unfortunately, I did not have these photos available during the failure of my PC, which is why I've initially only orientated myself by the first photo at the beginning of the post that I had on my smartphone, but what unfortunately has led into the wrong direction when I began scratching the arrangement, but what I still want to present to you. When scratching this fitting, I had to consider the support rod for the SRBs and drill a respective boring. For the two-part basic body of the fitting I've used a Rectangular profile (2 mm x 2,5 mm), which I rounded off at the front end to simulate the Bolt Catcher and drilled out for the holding rod with Ø 1,5 mm, as one can see in this image. On this image one can see the assembly of a Bolt Catcher, which catches the front part of the bolt that was blasted off when the booster was separated, Source: NASA whose honeycomb-like inner structure can be seen here in detail. Source: NASA The individual parts of the ribbed back part I cut from an Evergreen Strip (0,25 mm x 2,0 mm), and then glued step by step with MEK onto the basic body laying on a Teflon foil. Gluing the tiny triangles was a pretty tricky task due to the minimal spacing, but has worked well thanks to my angelic patience and steady hand. This was followed by the side attachment of the boxes on the front, which I could only reconstruct on the basis of my smartphone picture, what then looked like that. For modeling the arrangement on the back I've used this photo of the ET-45 (STS-47), although one can only guess it. Source: georgesrockets.com (George Gassaway) But I think that it can only be a simple cover, if one looks at this zoom shot, which is why I've chosen this simple form. And so the finished fitting sits on the SRB, and that's how the whole thing looked with the attached SRB onto the ET, actually not bad, right? But now I'm a bit smarter and know that the two boxes on the front are not sitting next to each other but have to sit one above the other, which is why I still have to change it once again, but be that as it may! Edited March 21, 2020 by spaceman Quote Link to post Share on other sites
The Underdog Posted March 22, 2020 Share Posted March 22, 2020 2 hours ago, spaceman said: Hello guys, unfortunately I was out of action for a while because my PC gave up the ghost, but my son has built me a new one so that it can go on. Manfred, Good to know it was just the PC gone bad, and not something worse with the virus going around. The updated photos and narratives, on how you've gone about creating the SRB/ET units which connect those items together - is simply amazing. Not only do we get to enjoy you building this excellent representation of 'The Shuttle Stack' on the Pad, but we're learning a lot about the entire vehicle and how its made. Win-win for everyone who's watching the entire process with great anticipation! Quote Link to post Share on other sites
K2Pete Posted March 22, 2020 Share Posted March 22, 2020 I agree with Underdog 100%! ... plus you're doing this exceptional work on a tiny, itsy-bitsy scaled model ... taking note of your "angelic patience and steady hand. " Indeed! Pete Quote Link to post Share on other sites
spaceman Posted March 22, 2020 Author Share Posted March 22, 2020 Thanks Underdog and Pete for the appreciation of my work, which gives me strength and continues to spur me on my journey ... Quote Link to post Share on other sites
The Underdog Posted March 22, 2020 Share Posted March 22, 2020 4 hours ago, K2Pete said: I agree with Underdog 100%! ... plus you're doing this exceptional work on a tiny, itsy-bitsy scaled model ... taking note of your "angelic patience and steady hand. " Indeed! Pete 3 hours ago, spaceman said: Thanks Underdog and Pete for the appreciation of my work, which gives me strength and continues to spur me on my journey ... Thanks Pete, We know and understand a "good thing" when we see it. Manfred, My praise and compliments are more than well deserved, you've done and continue doing a stellar job on this build. And, even when something has gone South - you've "stayed the course" and have overcome in fixing the process. You should be proud, of what you've been able to accomplish. I think its fair to say, not many modelers on this forum would have the patience, attitude and skills in doing what you do! Quote Link to post Share on other sites
spaceman Posted March 22, 2020 Author Share Posted March 22, 2020 (edited) Thanks my friend, in this difficult situation you have to distract yourself all the more and try to think of other things ... Therefore I am glad that my new PC is running and that I can still access all my data on my old hard drive. Unthinkable if the HD hadn't survived ... Edited March 22, 2020 by spaceman Quote Link to post Share on other sites
mikephilippens Posted March 25, 2020 Share Posted March 25, 2020 On 3/23/2020 at 12:32 AM, spaceman said: Therefore I am glad that my new PC is running and that I can still access all my data on my old hard drive. Unthinkable if the HD hadn't survived ... You do make backups, don't you? Just an external HD to which you copy your data from time to time is the least. Doesn't cost much and is easy to do. Better is a NAS like a Synology, but that's a bit more expensive and (depending on your computer skills) a bit harder to work with. Mind you: even external HD's don't have an eternal life...so take care of your valuable data. Quote Link to post Share on other sites
spaceman Posted March 26, 2020 Author Share Posted March 26, 2020 Thanks Mike for your well-meaning tips, backups are absolutely important and are also done, that goes without saying, only the last was a long time ago ... Quote Link to post Share on other sites
spaceman Posted April 4, 2020 Author Share Posted April 4, 2020 (edited) Hello everybody, today is an important historical date for my project, which I would like to honor with a brief review. 37 years ago today, on 4 April 1983 took off from the Launch Pad 39A the Space shuttle Challenger for her maiden flight, the STS-6 Mission, to whom I have dedicated my long-term project. Source: NASA And now back, here comes the next update. In the meantime I have modified the ET/SRB Forward Attach Fittings a little bit, so that the two boxes with the cabling are now arranged one below the other as in the original, as was already shown here. Source: forum.nasaspaceflight.com (woods170) Admittedly, this is only a small part of the entire Shuttle stack and can hardly be seen in the end, but if I am not completely convinced by the details, then I get to the bottom of the matter once more, something this time took longer because I've researched some sources more exactly again. And this is how the new part looks with the boxes arranged one below the other, and here again in direct comparison with the previous variant (left). Since the new prototype initially seemed a bit too big to me, I've reduced it a bit in a second variant (below), what one can see here. But after a detailed re-measurement based on the original photos, I still decided on the first, slightly larger version and made a copy of it for the other fitting. In the meantime I have also found a photo of the back of the fitting (left), which at first glance hardly differs from the front side (right) where the two boxes with the ET/SRB RSS cross-wiring were mounted. Source: forum.nasaspaceflight.com On the back there are no additional attachments like on the front, but only the receptacle for screwing the Ground Handling Fitting for the transport of the ET, Source: System Definition Handbook SLWT, Vol. I (Lockheed Martin) which was probably covered with a cladding, which one can guess more on this picture than can see clearly, Source: georgesrockets.com (George Gassaway) what I simulated by these tiny parts. And so these attachments sit opposite each other when installed on the SRBs. And this is how they look in the glued state, here is the view of the front of the ET, which is facing the orbiter, and here's a look at the back. And with that I wish everyone a nice Sunday, and above all, stay healthy. Edited April 7, 2020 by spaceman Quote Link to post Share on other sites
crowe-t Posted April 7, 2020 Share Posted April 7, 2020 Manfred, Outstanding job on these parts! Mike. Quote Link to post Share on other sites
spaceman Posted April 7, 2020 Author Share Posted April 7, 2020 (edited) Thanks Mike for your nice compliment. Unfortunately there are a few inconsistencies regarding the front and back of the ET/SRB Forward Attachment, which still seem suspicious to me. On the left during the Rollout of the ET-8 (STS-6) one can clearly see the FWD Hoisting Lug sitting on the "front side" of the ET and pointing up , and on the right, what also shows the ET-8 "front side" it looks like the arrangement with the ET/SRB RSS cross-wiring, strange ... That doesn't go together ... The same arrangement can be seen in this photo from the STS-8, Source: forum.nasaspaceflight.com (Ares67) as well as from the STS-9 too. Source: NASA Both arrangements would correspond with that of the STS-6 (first image, right). On the other hand, there are no holes on the FWD Hoisting Lug (right) for the assembly of the ET/SRB RSS cross-wiring boxes, which one can see in the left image. But in this screenshot from a Pad 39A walkdown video taken during the STS-133 pad flow it can be seen that these ET/SRB wiring boxes (with a gray fairing) are not sitting on the "front" but on the "back" of the ET (the side that facing away from the orbiter). Now the expert is amazed, and the layperson wonders, right? This view shows up at 2:36, here you go! How does that fit together, or not, what do you think about it? Maybe someone in ARC knows about this matter? Edited April 11, 2020 by spaceman Quote Link to post Share on other sites
spaceman Posted April 9, 2020 Author Share Posted April 9, 2020 ET experts for the early Shuttle missions don't seem to exist here either, too bad ... No matter, I now leave my Attachments as they are and that is that. Quote Link to post Share on other sites
crowe-t Posted April 9, 2020 Share Posted April 9, 2020 Manfred, I would go with the parts you already made. It's hard to find good pictures from the early missions. Mike. Quote Link to post Share on other sites
spaceman Posted April 9, 2020 Author Share Posted April 9, 2020 Thanks Mike for your response. This is what it looks like, and I like it the way it is. Quote Link to post Share on other sites
mikephilippens Posted April 10, 2020 Share Posted April 10, 2020 Murphy's law dictates that when you've finished your model, you'll find a picture that contradicts this... 😉 Ok, I'm kidding. What you're doing is above and beyond what anyone has done. And it's brilliant, this topic is such a treasure chest for others who are building a Shuttle. Or other models. The techniques you apply and the ways you look for information are inspirational! You're a teacher, no, a professor. Keep going and we keep watching this topic with open mouth... 😮 Quote Link to post Share on other sites
The Underdog Posted April 11, 2020 Share Posted April 11, 2020 Manfred, I'm amazed and flabbergasted at the progress you're making. I know and understand how picky you are about, perfection and attention to details. Sometimes, its alright to just sit back and "enjoy what you've been able to create and let it ride." As an artist, when I'm doing a painting there comes a time when I've tweaked it to the point that - if I do anything else to it, I'll probably regret it and have to fix it. You've been doing an amazing job, probably no one else could do what you're doing at this level. A project that won't be completely replicated anytime soon, or maybe ever! And that is a compliment about you, and the modeling skills you have perfected. Quote Link to post Share on other sites
mikephilippens Posted April 11, 2020 Share Posted April 11, 2020 👆 What he says! ☝️ Quote Link to post Share on other sites
spaceman Posted April 11, 2020 Author Share Posted April 11, 2020 Thanks Mike and Underdog for your praising words, which are very flattering to me. I am glad that you like my work so much and that it inspires you too. Sometimes one can only find the right photos when everything is done, but I can live with that. Nobody and nothing is perfect - also no kit, no model, and I don't either. Quote Link to post Share on other sites
spaceman Posted April 16, 2020 Author Share Posted April 16, 2020 Hello everybody, in our German Raumcon Forum I received a tip about the "Space Shuttle Technical Conference" from 1985, the both parts of which I found on the NASA Technical Reports Server (NTRS) and have skimmed over Easter. Part 1 (227 MB) - Part 2 (198 MB) ... Unfortunately, I could not find any information in order to clarify the said discrepancies regarding the ET/SRB Forward Attachments, which I have noticed on some early missions' photos. Regardless of this, one can find a wealth of interesting information in the conference contributions, which I have looked at here and there in more detail, provided that they did concern the ET and/or the SRBs and contained corresponding photos. And so I'm among others came across a Term I had been tampering with for a while already without getting to the bottom of it ... This is the term RSS Fairing, which was most recently used in this drawing of the Forward attachment. Source: System Definition Handbook SLWT, Vol. II (Lockheed Martin) The term Fairing as such was already familiar to me from the front fairings of the LO2 Feedline and the GH2 Press. Line on the Intertank. I was only irritated by the abbreviation RSS, which I'm of course familiar regarding the Rotating Service Structure, but wich has nothing to do with it. But as I have now learned from a conference contribution (EXTERNAL TANK PROCESSING FROM BARGE TO PAD), with RSS is meant the so-called Range Safety System, which I did not know so far, but which was of extraordinary importance as a safety system for all shuttle missions. And as it is often the case, I was so interested that I pursued this in a targeted manner and tried to find out more information about the task and function of the RSS. With this is also related to the term ET/SRB RSS cross-wiring, which my friend DaveS from the NASA Spaceflight Forum mentioned during a lengthy PM chat, which only increased my curiosity. And with that we are right back to these white boxes on the "front" of the ET/SRB Forward Attachment, which can be seen here both in the opened and in the cladded state, the upper half of which belongs to the ET and the lower half to the SRB. In the left image one can see the RSS cabling between the ET and the SRB for the STS-103. The Space Shuttle's Range Safety System (RSS) thus enables the destruction of both the SRBs and the ET using on-board explosive charges (Linear Shaped Charge, LSC) by radio remote control from the ground station by the Range Safety Officer (RSO) in the event that the shuttle stack gets out of control to limit the danger to people and facilities on the ground from crashing pieces, explosions, fire, poisonous substances, etc. ... This drawing shows these LSCs on the ET/SRB, as well as the associated receiving antennas, the Range Safety Command Antennas. Source: NASA The RSS was only connected to the LSCs, but not to the SRB separation system, which was wired separately. As I also know by DaveS, the RSS was cross-wired for security reasons, so that an error could not impair the ability to destroy the stack. The cross-wiring ran from the left SRB-RSS through the ET to the right SRB-RSS and vice versa. In this way, failure of one SRB's RSS cabling would not affect its ability to be destroyed, since the security cabling always was ran from the other SRB too. The RSS was activated only once - during the Challenger disaster (STS-51-L), 37 seconds after the orbiter broke apart when the SRBs were in uncontrolled flight (Source: wikipedia.org). And with that once again back to the above-mentioned discrepancies regarding the ET/SRB Forward Attachments. These can only be explained by the fact that the RSS cross-cabling in the early missions was probably more done on the "front" (-Z side) of the ET than on the "back" (+Z side). So much for my little Easter walk for those interested. Quote Link to post Share on other sites
Slartibartfast Posted April 17, 2020 Share Posted April 17, 2020 Nice info! Quote Link to post Share on other sites
K2Pete Posted April 18, 2020 Share Posted April 18, 2020 My goodness, your skills never cease to amaze me! I have to say that it amuses me when you ask US for advice on building this vehicle. WE look to you for your knowledge. And the information you have unearthed, and shown us is overwhelming. I have a 1/72 Shuttle stack in the stash but I cannot visualize keeping my interest at the level that you have. To continue to conduct research to find that elusive detail and THEN replicate it in 1/144 scale ... astounds me. The incredible reference photos you've located ... I often wonder ... "Where the hell did he find those??" Manfred, stay healthy ... but for my own selfish reasons. I want, and nee-e-e-ed, to see this project completed! Even if it's just the MLP and Shuttle Stack painted ... Pete Quote Link to post Share on other sites
The Underdog Posted April 18, 2020 Share Posted April 18, 2020 Manfred, I've been wanting to find and build an elusive, 1/72 scale Shuttle Stack - but they're so difficult to find in the Brand-new condition. So, instead I've been motivated by the way you've gone about working on this build project, and purchased a couple of 1/144 kits of the Revell Shuttle Stack. I agree with Pete, "stay well and looking forward in seeing this amazing project and model completed someday soon!" Quote Link to post Share on other sites
spaceman Posted April 18, 2020 Author Share Posted April 18, 2020 (edited) 4 hours ago, K2Pete said: My goodness, your skills never cease to amaze me! I have to say that it amuses me when you ask US for advice on building this vehicle. WE look to you for your knowledge. And the information you have unearthed, and shown us is overwhelming. I have a 1/72 Shuttle stack in the stash but I cannot visualize keeping my interest at the level that you have. To continue to conduct research to find that elusive detail and THEN replicate it in 1/144 scale ... astounds me. The incredible reference photos you've located ... I often wonder ... "Where the hell did he find those??" Manfred, stay healthy ... but for my own selfish reasons. I want, and nee-e-e-ed, to see this project completed! Even if it's just the MLP and Shuttle Stack painted ... Pete Thanks Pete for your always repeatedly truly refreshing contributions. Perhaps it is too much to ask, but sometimes a reference to a good source also helps. Yeah, high-quality reference photos are for every scratch modeler, of course, that's what gives it that extra something, which one often has to look for like for a needle in a haystack, but seek and one shall find! Of course one needs excellent sources, a widely ramified network and competent experts. But even they sometimes do not have exact answers to all of my unusual questions, or some remain then elegant silent ... Then one has to be patient and persistently ask again, sometimes that helps ... BTW, I can fully understand your curiosity well, but it will still take a while until the stack will be standing on the MLP ... Therefore stay tuned and healthy too! Edited April 18, 2020 by spaceman Quote Link to post Share on other sites
spaceman Posted April 18, 2020 Author Share Posted April 18, 2020 42 minutes ago, The Underdog said: Manfred, I've been wanting to find and build an elusive, 1/72 scale Shuttle Stack - but they're so difficult to find in the Brand-new condition. So, instead I've been motivated by the way you've gone about working on this build project, and purchased a couple of 1/144 kits of the Revell Shuttle Stack. I agree with Pete, "stay well and looking forward in seeing this amazing project and model completed someday soon!" Thanks Underdog for your good wishes, I do what I can. Take care of you and stay healthy too. Quote Link to post Share on other sites
spaceman Posted April 29, 2020 Author Share Posted April 29, 2020 Hello everybody, after a longer breather I want to get back in so that I can’t get out of the exercise. Therefore I want to leave the SRBs for the time being and address myself to the ET to start preparing him for the Flour coating, wherefore I first have to glue the tape strips for simulating the SOFI Pattern texture both on the LH2 Tank and on the LO2 Tank. For this I can resort to my preliminary tests from last year, in which I used a 0,75 mm wide tape strip as a continuous spiral (Barber pole) onto the Airfix Intertank which is no longer required, which at the time looked like this after the Flour coating. So I came very close to the pattern texture of the ET-8, whereby the final result should probably look even a bit better after priming and painting. As one could see at this image, the SOFI patterns on the ET Aft Dome are significantly wider than on the front part of the tank, which I wanted to take into account. Source: forum.nasaspaceflight.com (Jester) After taking a closer look at this structure once more, I decided to use 1,5 mm wide tape strips, of which I've then glued short strips on the Aft Dome at intervals of about ≤ 1 mm for testing. Before that, of course, I had removed my fragile Aft ET/Orbiter Attachment and put it in a box to safety. On the front part there are glued the chosen 0,75 mm wide strips, at intervals of approx. 0,5 mm. So I could imagine that way. What do you think about it? Quote Link to post Share on other sites
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