Space Shuttle Launch Pad 39A with Challenger STS-6

[roma847]

Hi folks,

here is 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?

[RichO]

Almost looks like some sort of bleeder valve, maybe pressure release valve.

[Nigel Heath]

As they all look to be at the highest point in the pipes I'd say they were vents to clear air out of the system.

[roma847]

Thanks Rich and Nigel for your ideas.

But 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 they 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.

[RichO]

That,s right up your PhD area Manfred, you would know better than the rest of us about material analysis and structure stress.. Your idea of an inspection port is probably the correct one.

[roma847]

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.

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.

[Mustermark]

Yes, stick with that. It looks great.

Soon you will need to be holding atoms in your tweezers and making nanomolecules!

[roma847]

Thanks Mark for your nice comparison,

but I'm not a magician.

[roma847]

Hi there,

Today I want already times to have a look ahead how it goes on shortly.

There are still these two 9'' outlets (Ø 1.4 mm), which branch off before the 12'' outlet from the 24'' ring line, then run through below the SRB Blast Shields,

Source: NASA

and feed the line with the outlet nozzles on the rear wall of the SSME exhaust chamber,

Source: NASA

which I have completed for some time, as well as the tricky Firex line.

And at the other end of the 24'' ring lines it goes on behind the TSM's with the 16'' rejuvenations (Ø 2.5 mm) which are tapering one more time to 11'' (Ø 1,8 mm) after the first bending,

Source: NASA

and end in the SSME chamber in these pipes stocked with eight outlet nozzles.

Source: NASA

In order to continue with these details, I had to make measurements and scalings again.

And as it looks like, it will be probably again pretty tricky, I guess.

[roma847]

Hello everybody,

here still a small addendum to two outlets that are missing yet, these are namely those four 6'' outlets (Ø 1 mm) here, which although were to be seen already, but have not yet been regarded.

Source: NASA

These transitions branch off from the ring lines, run under the SRB Blast Shields, and reappear between the front SRB Supports, whose ends with the outlet openings also already exist.

And the two 24'' ring lines are fed in through these two 36'' inlet pipes in the corners of the SRB-wells that were already shown also.

Here is the upper confluence into the ring line,

Source: NASA

and here the lower end with the coupling elements,

Source: Troy McClellan

which must not be missing.

And in order that during the further adaptation and assembly of various outlets everything goes well and the ring lines cannot shift constantly themselves, I have precautionally carved even more mounting aids.

These mounting aids are then certainly also indispensable during subsequent assembly of so many pipe supports.

[RichO]

More fun times Manfred!

[Chillitt]

Maybe the bolts are help the system drain after use. You wouldn't want the large scale equivalent of the upside down glass of water trick going wrong to happen when you have people working around there.

[roma847]

Thanks Rich and Chillitt, let's keep on pipe bendings.

Hello everyone,

initially I still want to show the two 12'' outlets, which now have got their outlet openings and baffles as well as the nipples.

And after that it initially went on with the 9'' transitions (Ø 1,4 mm) of the 24'' ring lines (Ø 4 mm), standing on a tall support pillar.

Source: NASA

What on the pictures firstly looks really practical and invites for scratching, then pretty shrinks on the 1:1 Sketch again.

After determining of the dimensions of the components began the search for suitable profiles. For the pillar Evergreen rods are suitable with Ø 1 mm (bottom) and 1,4 mm for the upper sleeve, on which a flat 2 mm U-profile sits and on this a small "Sickle". Of the width for the U-profile a corresponding Evergreen channel would be suitable, but is unfortunately too thick for this filigree support and the sides with 1 mm too high.

That's why I prefered to bite the bullet and have scratched the profile of 0.15 mm Styrene. For the sides I have sanded down an Evergreen strip 0.25 mm x 0.5 mm to 0.15 mm and then glued with MEK.

And the difference is clearly visible, as one can see here.

Then bending was indicated again, this time with the 1.4 mm rod,

what agrees very well with the sketch.

After that I've drilled a hole with 1.4 mm in the front inner corner of the SRB Blast Shields, and made a test that was okay instantly.

And that also fits well with the underlying 12'' outlet.

Now is still missing the support pillar, which I'll make tomorrow.

[Mustermark]

Good job. Perfect first time... all the practice pays off!

[roma847]

Thanks Mark,

yep, my bending method under hot air and with Balsa jigs has so far proven itself optimally and has been patented meanwhile - Made in Germany!

[Richard E]

One point no one else appears to have mentioned: the engineering thought that has gone into the original launch tower is almost as impressive as your model.

[roma847]

Thanks Richard for your great compliment!

Now that's going too far, first and foremost comes the ingenious technical masterstroke of NASA scientists and engineers, that fascinates me anew every day.

I can only try to build a good copy and to give my best to capture some nice details. ...

[Thom216]

The way you could top what you're doing, is to have this beauty motorized and the shuttle able to launch!

[Mustermark]

One point no one else appears to have mentioned: the engineering thought that has gone into the original launch tower is almost as impressive as your model.

Yes... *almost*

[roma847]

The way you could top what you're doing, is to have this beauty motorized and the shuttle able to launch!

Thanks Thom,

what a beautiful imagination, let's all together dream on ...

[roma847]

Yes... *almost*

Thanks Mark,

I'm lost for words ...

[roma847]

Hello again,

but initially the 9'' outlet still received a few small details.

At the feedpoint of the 24'' ring line is a small thickening to see, for what I have punched a small Styrene disc (0.5 mm) with Ø 1.6mm, which has already been glued, as can be seen in the following figure.

Due to the small diameter of the outlet of 1.4 mm also the diameter of the nipple is correspondingly smaller with only 0.3 mm, for what only a tiny hole were to drill,

into which my thinnest rod with Ø 0,3 mm was glued. Next to it is a lead wire with a diameter of 0.3 mm, which I will use for the clamping ring on the other end.

The lead wire I have glued with CA.

And so the final outlet looks, from which I still need a second copy.

And now to the slender support pillar, which stands under this outlet and consists of six parts,

Source: NASA

which I have already prepared and are all quite tiny,

which must be glued together now.

And I can tell you, the mounting should become a tricky matter due to the minimal contact surfaces.

Since I glued these things with normal Revell glue for possible corrections, one can not continue, but must wait until hardening.

And the height of the support I should also check from time to time, since it should not exceed 9 mm in order to fit even under the outlet.

And for that reason alone every now and then a break is necessary, like now, why the base plate and the top plate have to wait.

[roma847]

Hello everybody,

and here is the next update.

Since I still wanted to check the total height of the support pillar, I have not initially sanded the tiny rounding in the upper pipe holder, especially since it is anyway only 1 mm x 1 mm "big".

The problem with this prototype is, that the height of the components should be exact as possible on the tenth of a millimeter, if in the end should be reached the calculated required total height of 9 mm, so that the support fits under the transition.

Subsequently, the support was positioned on the base plate and glued,

and then vertically aligned on all sides vertically.

And so the filigree structure looks, which is very fragile and wherefore the further handling is to enjoy with caution.

With the optical look of the support I am already very satisfied, although actually still missing these two screwings,

Source: NASA

which I wanted to try at least times. In my estimation, one could scratch it by thin rods, which would, however, which would be again in the boundary region of the nipples with Ø 0,3 mm.

That would be even doable, although this strip (0.37 mm x 1.5 mm) is slightly wider than the only 1 mm wide plate under the pipe holder,

and through the shadows it could be seen even better in the painted state, questionable would be, however, from what distance ...

But more important is the question whether and how the support would fit at all.

And to my surprise, it fits already together relatively well,

although the left side of the pipe hangs a bit in the air, as can be seen more clearly in this close-up.

But this should be still compensable if I sand even a tinier rounding in the tiny pipe holder (1 mm x 1 mm) and it plays along.

Although this support was quite tricky, this looks but overall very well.

[roma847]

Hi there,

making of the tiny rounding was not a problem, especially since only a hint of 0.15 mm was necessary.

And here is the result,

and because the transition now sits a little bit lower, so far everything is okay.

Therefore, the rounding of the second pipe holder will be made before assembly.

[John_W]

I am watching this and imagining the detail you are going to add to the Shuttle...