Space Shuttle Launch Pad 39A with Challenger STS-6

[roma847]

Thanks Joe for your interest.

Hello friends,

after reconstructing and re-lining of the SSME exhaust hole is missing a small detail of the SRB Blast Shields, namely the posterior transition to the Blast deck, which can be seen in this picture.

Source: NASA

As can be seen in more detail on the panoramic image, the transition behind the SRB shafts is covered by metal strips that are overlapped at the front edge of double fold-strips which are bolted to the Blast Shields. And this covering strips I wanted to at least hint at something.

Thus, the transition looked previously,

and these are the strips of paper for it with the details indicated.

And here the strips are "screwed" and the transitions now complete.

Next, it then goes on to the tube with the nozzles in the SSME hole, I've changed something.

[roma847]

And so it went on.

Since my first two prototypes of the rear SSWS tube with the six vent nozzles were not really been successful, I've made a few thoughts before the third test in order to come to a more practical and better solution.

This time I actually wanted to use 0.5 mm copper wire for the nozzles, because one can bend it relatively easily and accurately and the rounding remains but plastic profiles usually tend to bend back, something you need to consider.

But the mounting of these copper nozzle is not without problems, since one must again stick with Sechu this pairing and the seat therefore should right the first time. However, as already inserting these tiny kringle in the small holes is quite cruelty, I've discarded this method then again and stayed in Styrene and MEK. With this method, you can calmly stuck in the nozzle in the holes and fix the seat even before the MEK is painted for bonding to the junction.

In order to compensate for the subsequent widening of the nozzles after bending better, I have initially forced into this tight corset of three rulers,

and thus can control and regulate the widening better.

And so now the holes for the nozzles. Since the position of the holes was too uneven in the first experiments, I have been thinking this mounting bracket of balsa slats as a courtesy to further handling , which has already proven to be a suitable stop when marking and drilling the holes.

The nozzles I first consciously sized bit longer in order to put them so easily into the bores and still be able to align. Only then I wanted it cut to a uniform length.

Here, the nozzles are already stuck into the holes but not glued.

And now followed the next step in the mounting bracket. To set uniform distances (about 1 mm) above the tube I have put a fitting aluminum angle profile under,

fitted the protruding ends with a steel profile and aligned again. And only now I gently applied the MEK with a brush.

Then I've marked the final length of the nozzle row,

and cut off the ends on a steel ruler with the cutter.

And this is now the result with which I am finally satisfied.

And also the seat of the tube on the rear wall is correctly so that it now only needs to be painted.

That's it for today, see you soon.

[noeyedears]

nice job, you are totally mad,

[roma847]

Thanks for the kind words, just half as bad!

[roma847]

Today I want to continue with the SSWS pipes at the front end of the SRB holes that I had ever been shown.

Source: capcomespace.net

In this picture you can see the arrangement of the two pipes between the SRB supports even better.

Source: capcomespace.net

And so do the associated templates from the Paper Kit look like, here is the lining of the back wall, although belonging to the other hole, but very similar to the real thing.

And here's the cover of the SRB-Blast Shields with appendages from which one should now conjure these pipes with 1 mm diameter.

But since I do not even want to try out, I'll scratch these details again in plastic and start with the left hole pipes.

For the pipes I've used Evergreen Rods (Ø 1 mm) and for the lower bracket L profile (2,5x1,5 mm).

The pipes are not glued, as they still need to be cut down after fitting.

Then I have already drilled the holes in both Blast Shields to fit the pipes.

And as you can see, the first pair of pipes fits after some corrections quite well. Where the profile is inserted, yet little support underneath come later.

Now the pipes at the lower ends but even have those baffles, and they were a bit trickier. These are styrene strips (0.2 mm), which I glued again with MEK and then cut.

And so it looks like so far.

A few things are still missing, but tomorrow it then continues with the second pair.

Edited March 20, 2015 by roma847

[phildagreek]

Wow. Just wow. Really impressive work. Stunning stuff.

[RichO]

Good job Mr. Bender! The pipe work always look great!!

[roma847]

Thanks guys for the kind words.

Hi there,

before I started with the second pipe pair, I still have experimented a bit with the mountings of the pipes. Unfortunately, the photos of these pipes are not sharp enough to see the details more closely. But I mean, there are holding clamps with which the pipes are connected to the brackets on the rear wall. The middle clamp is clearly a clamping ring for detachable connection of pipes, as can be seen in many places of the thicker SSWS pipes. Perhaps this middle clamping ring is only a sleeve.

And this I have tried to indicate by a tape roll and a sleeve made of aluminum foil, whereon the clamping ring is stting, made of lead wire (0.2 mm). But the handling is already at a single round profile a pretty tricky matter,

let alone the finished pipes pair.

Therefore, I have decided to omit the sleeve and to indicate only the clamping ring.

For the small brackets I finally used tiny T-Beams made of Evergreen strips,

which then end up looks like this.

So far so good, and therefore, now to the construction and assembly of the pipes in the other hole in an analogous manner.

And so back to the trickier detail steps in the installation of mini-brackets, baffles and clamping rings in the following pictures.

The conclusion was again the stressful attachment of the lead wire, since gluing must be done with CA. If namely the first gluing is holding not immediately, there are problems, because then you have to remove the CA again only what is in these mini-contacts really crude. And then the excess wires must be removed with the cutter. It can happen, that the wire ring redissolves or breaks off the bracket.

But then the second pipes pair was finally made,

andthe pipes look like after the final fitting in the SRB holes,

which can be painted now.

Edited March 25, 2015 by roma847

[roma847]

Hi there,

so that the paint is also worthwhile, I will scratch build the next part of SSWS pipes. It is this line here, which runs around the SSME hole, as you can see here on the templates of the Blast Shield covers from the Paper Kit.

Thereafter, this ring line should obviously run through the TSM's, which is not true, as you can see in the following image. Then the supply lines come in front of both TSM's from the MLP-deck and then branch into a strand with several nozzles along the hole, and down into it.

Source: NASA

In this picture you can see the rest of the line that runs along the top of the hole on the inside of the TSM's along and then again to the top and around the hole.

Source: NASA

As you can see in the pictures and panoramic shots, this rear part of the line over the entire length has also a series of water nozzles.

Source: NASA

So much for this line, now I need only to determine the dimensions of the associated supports and nozzles, and then I can start with the scratch building. The diameters of the pipe and water nozzles correspond with 1.4 mm and 0.5 mm with the already finished nozzles pipe on the rear wall.

[RichO]

Can't wait to see you lay some pipe!!

[ScarecrowJoe]

When you finish this there will be a world shortage of styrene tubing! LOL! Looks awesome.

[roma847]

Thanks Guys,

yep, the SSWS chapter is a great challenge and needs a lot of patience.

[POTKC]

Hello there...is this the same build that I was reading about on papermodelers.com forum last year? I haven't been on there for some time...?

[roma847]

Quite right!

[Kallisti]

Blimey that looks complicated but lets face it "complicated" might as well be your middle name

[heloman1]

I haven't visited your build thread for a while, looks like the loss is all mine. Excellent work on the piping.

Colin

[roma847]

Thanks Guys for your kind compliments, especially Kallisti for your nice middle name.

Hi there,

before continuing with these pipes, I have to correct something my last post.

The presented piping system is not a part of the Sound Suppression Water Sytems (SSWS), as I had previously thought. As I have discovered these pipes belong to the Fire Suppression System which is activated as a result of problems with the SSME main engines and means a launch cut off (Redundant Set Launch Sequencer - RSLS - abortion) at the last moment immediately before the SRBs are ignited.

I came across it in the evaluation of the reference material for the determination of the dimensions of the pipes and water nozzles, so among other things, when viewing photos and videos of SSWS tests. One can always only see the larger SSWS systems in the three exhaust holes and the Rain birds in action, but never these pipes of the SSME hole, but would not surprise, considering the haze of the massive volume of water.

But then I reminded me of pictures, especially where the fountains of water sprays were seen on both sides of the front hole in action, but just did not know where I should be looking. After a longer investigation of photos and videos from launch aborts I've then been able to find and hit the STS-41D, in which such a RSLS abort took place for the first time. Similar aborts there were also in the missions STS-51-F, STS-51, STS-55 and STS-68.

In this STS-41D-Video (from 4:48) one can see these water fountains in front of and behind the LOX-TSM after activation of the system.

And after this very interesting technique escapade again to practice and first again to the laborious determination of the required dimensions.

Here is my first time rough sketch with all sorts of sizes/calculations and positions of the pipes with spray nozzles from the Blast Shield on the back wall to the front of the SSME hole,

and here is my scale drawing with the supports (green), clamping rings (red) and the 25 spray nozzles (black), but this is hardly visible at this resolution.

And here are the materials that I want to use,

round profiles Ø 1.4 mm and 0.5 mm for the pipes and nozzles on the Blast Shield, an Evergreen strip 0,75x0,38 mm for the supports and 0,2 mm lead wire for the clamping rings and brass angle profile 1x1 mm for the supports below the TSMs.

That's it for today, and tomorrow I will throw myself then boldly into this pleasure.

[noeyedears]

wow thats an awful lot of work for a few pipes mad and brilliant in equal measure

[roma847]

Thanks for your nice words,

I fully agree with you, and as I've said, the SSWS with all the tiny pipes and supports is a tricky chapter and a great challenge.

BTW, this Fire Suppression System David Maier has only indicated on the SSME Blast Shield, but I will try to scratch build.

I'm not sure if I can build all the details as planned, we will see ...

[RichO]

I've noticed that the David Maier kit dose have the pipes indicated on the print. This is adding a nice bit of detail when you add the scratch pipes on top of the print. I like the stronger shadow line and detail indicators. Great job!!

[roma847]

Thanks Rich,

yep, 3D details look better than 2D print, the only problem is, that the details in the photos look so large, but for scratch building in 1:144 is all very tiny.

[mirageiv]

[roma847]

Hi, just before the Easter holidays,

and now ready to begin the pipe bending for Fire Suppression System, in which I want to go step by step. Although I'm not sure if I will be able to turn the whole line at once, but I will at least try. If not, I would have to split the line, usefully then in each case on one of these supports below the TSM's, or on the clamping band right, and cover the connecting point with it.

Source: NASA

The strands already shown with the two nozzle pairs forward before the TSM's on the Blast Shield must be installed separately anyway.

Source: NASA

It was especially important to always compare the bends with the installation diagram,

as well as to try on the line on the MLP. And as you can see, that already fits to the LOX TSM around quite well so far, although such tests are a delicate matter and I put the precious part rather quickly aside.

And that would be one half of the line made before, and it goes around the corner to the LH2 TSM.

So that to make these bends more closely, I again used my Balsa retainers, which give it more stability,

and the TSM replaced by a Balsa dummy, which is tough.

To adjust the height of the missing supports (0,75x0,38 mm) I put underneath a corresponding Evergreen strip of appropriate thickness.

To bend the tight curves above the Blast Shield this old TSM silhouette is a good orientation.

And now the acid test with the two TSM's, which also is okay so far, both from the front,

and from the rear.

Now, of course, still missing a number of details such as the supports, clamping rings and nozzles at the rear part of the line, as well as the front two strands.

And then the ends of the line must be structured in front of the TSM's that I have provisionally made longer. And at the beginning of the line from the upper deck there is this thickening with the flange (see 2nd picture) that I at least wanted to indicate.

Source: NASA

So, there is already waiting still a lot of Easter fumbling for me ...

Let's see what I can still do until then.

Therefore, in advance Happy Easter!

[RichO]

Happy Easter to you Manfred and Elisabeth and family.

The Bending looks great, keep up the good job!

[roma847]

Thanks Rich and Happy Easter to you and Teresa, and to all your loved ones too.