Space Shuttle Launch Pad 39A with Challenger STS-6 (1:144)

[crowe-t]

Manfred,

Excellent work and attention to detail on the SSWS!

I can't wait to see the MLP all finished.

Mike.

[spaceman]

Thanks Mike for your appreciation.

I also cannot await to finally see the finished MLP, even with lighting.

When everything is completed one day, I'm sure it will look but scratch-building of all these tricky pipes and tiny supports is pretty stressful.

But I nevertheless will not let loose.

[spaceman]

Hello everybody,

quickly back into the pipe pleasure with the modified Balsa template whose upper flat bow is still somewhat narrower.

Important for the next 45° bending is at first the fixation of this slant and the separate extension of the abutment face, as these short pieces otherwise don't stay straight, but would rather become rounded.

To avoid this also during the following bending, even this small flat bow must be specially fastened previously.

And after bending I have preventively heated one more time in the clamped state.

After that all sides should fit closely on the template.

After that follows the last one, but at once the most difficult bending of the transition to the ring line around a relatively tight radius, because an exact positioning of the rounding template is important, but this is more or less a matter of feeling.

And this is the result.

Now the test must show whether or how well the outlet fits. And that now looks total already better than before. The upper bow is flatter and lies slightly lower than that of the forward 18''/12'' outlet,

and the support still has some space to get closer.

Meanwhile, the front outlet has been slipped down a bit, because the Pattex power subsides, be that as it may!

So much for today.

Edited August 23, 2016 by spaceman

[spaceman]

Hello everyone,

today for a change I have bent the missing second 24'' ring line (Ø 4,0 mm). While the thin 12'' outlets (Ø 2,0 mm) soften relatively quickly, this thicker rod must be reheated a little longer before one can bend it easily.

Otherwise it was the same procedure again, as you can see, whereas the roundings this time even have become better than at the first ring line, this makes the exercise.

And this is the next test, this time again with the Rainbirds, to round out the picture,

and here without the annoying placeholders.

[spaceman]

And so the upper deck is slowly filled by the SSWS, what looks .

And finally still a total view from the front.

That's it for today.

[crackerjazz]

Hi Manfred, you're a whiz at bending those pipes! Do you pre-bend the pipes with the heatgun then push them in between the balsa pieces and heat them up some more?

[spaceman]

Hi Joseph,

thanks for your nice compliment.

No, this would not work.

For example, the third bending of the ring line:

During heating of the bending point, you have to touch the rod with a Balsa board (see below), and at the beginning of the softening of the Styrene rod you bend its entire length until the template, but without much pressure!

After the board is fastened by the pins, one can preventively heat one more time.

And after cooling, you can unclamp, because then the desired shape is "frozen".

That's the whole secret.

Edited July 12, 2016 by spaceman

[spaceman]

Hello everyone,

today I want to come back to the 18'' outlets, which indeed still have no outlet openings. And also lacking even the little supports with which they are attached to the SRB supports.

That are these small metal sheets here,

Source: NASA

and then these here below the SRB supports immediately above the outlet openings.

Source: NASA

While the supports in the first image are simple square Styrene plates (2.5 mm x 2.5 mm x 0.3 mm), the lower supports have a trapezoidal shape because they sit on the slant of the SRB supports and on the flattened outlet openings. And this results in two little problems, one being the difficulty of determining their dimensions, and closely connected their mounting on the outlet openings below the support slants.

For the dimensions this image was relatively well suited. It can be seen that the outlet opening and the trapezoidal sheet ranges up to about the middle of the SRB support.

Source: NASA

Accordingly the size of the support is about 3.7 / 2.5 mm x 3.7 mm x 0.3 mm.

For the adaptation and assembly of these supports at the outlets, I have modified my previous mounting template for the tapered 18''/12'' outlets to the following Balsa jig which has the shape of the SRB supports.

The support is made of 8 mm Balsa and thus corresponds to the thickness of the SRB support. In the base plate beneath sits the 24'' ring line for an exact alignment of the 18'' outlet. As spacers I have used 2.5 mm H-beams (Evergreen).

Now I have fixed the location of the outlet from both sides and from above, so that it can no longer slip.

And in the gap between the support and the outlet end can now be adapted the trapezoidal support plate and also glued later.

But previously the outlet opening must be hollowed and flattened out.

[spaceman]

Therefore at first I have tried to pre-drill the outlet end as centrally as possible with smaller diameters (up to 2.4 mm), but this is not so simple and is slightly shifted again.

After the final drilling with Ø 2.8 mm, the wall is rather thin and unfortunately unequally thick,

which is unfavorable for the subsequent warm-flattening of the opening (on the left).

Another possibility (right) would be to use a drilled Styrene pipe (3.2 mm), of which the wall would be indeed more uniformly, but slightly thicker, which would be acceptable. The form itself certainly looks cleaner.

Of which now however still had to be cut off a short end piece and to be glued at the shortened outlet end, as well as additionally refinished, which would be an additional fiddling again.

Meanwhile, I've bought a drill with Ø 2.5 mm which hopefully is better suited, let's see ...

Finally, I have marked nor the positions of the upper support metal sheets.

Well then until soon.

[spaceman]

Hallo zusammen,

jetzt fehlen nur noch die Austrittsöffnungen, die ich ja nochmals probieren wollte.

Die Schwierigkeit dabei ist ja, wie gesagt, das mittige Bohren, das man nicht gleich mit dem Enddurchmesser machen kann, weshalb ich diesmal einen Dummy (Ø 3,2 mm) in kleineren Abstufungen aufgebohrt habe.

Nach dem möglichst mittigen Ankörnen habe ich zunächst mit Ø 1,3 mm begonnen, und zwar ca. 6 mm tief, d.h. immer schrittweise rein und raus, damit es keinen Spänestau gibt.

Und das sieht schon mal ziemlich zentrisch aus.

Danach folgten Ø 2,0 mm,

Ø 2,3 mm,

Ø 2,5 mm,

und schließlich noch ein leichtes Senken mit Ø 2,7 mm zur Verringerung der sichtbaren Wanddicke, halt wegen der Optik.

Und dann habe ich den vorderen Bereich (ca. 3 mm) mit einem Kern (0,75 mm x 2,5 mm) kurz vorsichtig erwärmt und schrittweise langsam platt gedrückt bis auf 1,7 mm Höhe, aber nicht etwa so ...

Und das kann sich, glaube ich, durchaus sehen lassen, oder?

Und somit kann ich mich wohl nun auch an die richtigen Abgänge wagen, hoffentlich klappt's dann bei denen auch so gut.

[spaceman]

Hello everybody,

now missing only the outlet openings that I wanted to try again.

The difficulty is, as I said, the central drilling, which you cannot do it immediately with the final diameter, which is why this time I drilled a dummy (3.2 mm) in smaller gradations.

After center punching as central as possible I first started with Ø 1,3 mm, specifically about 6 mm deep, that means gradually in and out, so there is no chip congestion.

And that looks already pretty centrical.

Thereafter followed Ø 2,0 mm,

Ø 2,3 mm,

Ø 2,5 mm,

and finally still a slight countersinking with Ø 2.7 mm for reduction the visible wall thickness, just because of the optics.

And then I have briefly heated carefully and gradually slowly flattened the front end (about 3 mm) with a core (0.75 mm x 2.5 mm) down to 1.7 mm height, but not this way ...

And that can be quite impressive, right?

And therefore I can probably now also venture to the final outlets, hopefully it'll work also as well then.

Edited August 23, 2016 by spaceman

[spaceman]

Hello everyone,

I have made a final test on a real component and thereto used my first 18'' outlet prototype, which still was lying around and anyway is good for nothing. He still had Ø 3,0 mm and was due to the bendings no longer circular at the end , but came just right as a dummy.

Its end I have drilled out to Ø 2,5 mm,

and then flattened, as usual.

As can be seen, one can scratch the outlet opening also directly at the bent outlet.

And therefore I can now also get down to business with the four final outlets (Ø 3,2 mm).

[spaceman]

Hello everybody,

and this I have implemented now, in hopes that it will fit somehow.

First, I have drilled out the final four 18'' outlets, as already described.

So far so good, and now came the cautious forming of the outlet openings with the help of the Proxxon Gun, for what I have inserted a core.

Nevertheless, one must be extremely careful during heating, so that the thin-walled opening is not shrinking suddenly.

And how the subsequent fitting shows, the position of the opening under the balsa support looks quite passable.

Edited August 23, 2016 by spaceman

[spaceman]

And now to the lower support plates, which can be seen in this panorama of the STS-134 on the MLP 2.

Source: NASA

First, I have tested my estimated size with a paper dummy, which was still a bit too small.

With the adjusted support plate of 0.3 mm Stytene it looks much better already.

So both plates can be glued now on the outlets in place.

[spaceman]

Hello everyone,

fast nor a quick update, the lower support plate was once more modified slightly and now stands vertically,

and then it was glued above the outlet opening.

And then came still the upper support.

That's it for today.

[Mknorr]

Beautiful work as always Manfred. 👍

Not sure why my subscription to this thread keeps stopping. 🤔

[spaceman]

Thanks for watching Manfred,

that's a pity, therefore you have to ask the admins.

Stay tuned my friend and enjoy.

[Vince Hoffmann]

Spaceman, I'm very impressed by your plastic bending skills, there is such a fine line between too much heat and not enough, you did a fantastic job on those pipes!

[spaceman]

Thanks Vince for your nice comment.

Yep, that's right, a bit too much heat can spoil everything.

And therefore my Balsa jigs like straightjackets are so important. At this helpful solution I have fiddled long time.

[spaceman]

Hello everybody,

but first times still an addendum to the current state of the first two 18'' outlets with the support plates.

And for the flattening of the outlet openings on the two other outlets I have my method still slightly modified.

The opening can in fact even be better formed when one first uses a balsa rod which is flattened out gradually during heating,

after which I've used one of the new opening adapted core.

And this gives a nearly perfectly shaped opening.

Because of the different running lower curvature of these two outlets I had to remodel my Balsa clamp jig laterally reversed for adapting the lower support plates.

Thanks for watching.

[crowe-t]

Incredible job on these Manfred!

[spaceman]

Thanks Mike for your nice compliment.

Hi folks,

here still a question to the expert round, what do you think wherefore these screwings are good for, which are located at all outlets (6'' - 9'' - 12'' - 18'') of the SSWS?

Source: NASA

Of which there are a total of 18 pieces, if I've counted correctly, although here some are covered.

Source: NASA

Are these possibly vent openings or inspection ports?

Edited July 27, 2016 by spaceman

[Slartibartfast]

At first glance I'd say those are high-point bleeds. Air gathers at high points in a liquid-filled system so means of bleeding air out are provided. I would assume that's only for pressure testing with the nozzles blocked off since they're normally open?.

[spaceman]

Thanks Slartibartfast for your reponse.

I think, that vents shall probably not come into consideration, because the SSWS pipes are only during the launch under pressure. The rest of the time the entire system is open, from the two 36'' feed pipes in the SRB exhaust holes

Source: NASA

to all outlet openings of the two ring lines.

Source: NASA

I rather think that these openings are probably some sort of inspection ports for access for Mini Cameras periodically to check the pipes for cracks and wear. Because at these pipe-bends the stress as well as the wear of the pipes are greatest, this makes most sense to me.

In this respect I coincide with Jay Chladek, who I have asked via PM.

[spaceman]

Hello everybody,

be that as it may, I've tried to scratch these nipples.

As already indicated, the nipples are relatively small in my scale (1:160), only about 0.4 mm/0.2 mm in diameter and about 0.4 mm high. :blink:

Source: NASA

If one would be pretty exactly, one might poke a brass rod Ø 0,2 mm into a brass tube Ø 0,4 mm with 0.09 mm wall thickness, as one can see here.

But the tiny "screw" on the right side is hardly to be seen still.

This couple one could now stuck into a 0.4 mm through-hole, but this effort is not worthwhile.

Therefore, I would be satisfied with a Styrene variant, whereto I have drilled out my dummy outlet

and glued a short stub Styrene Ø 0.4 mm.

And this stub I've then reduced to approx. 0.4 mm in height.

And since this result seems perfectly adequate, I will probably stick with it.

Edited July 27, 2016 by spaceman