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#960 by roma847 on 04 Jun, 2016 06:39
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Hi there,
and thus to this support detail, although this every now and then was caught in my eye, but it was not previously appeared as so important to me and I therefore omit wanted. That are these welded stiffening plates, which are barely visible in this picture of MLP-3.
Source: NASA
In this photo from the MLP-2 one can see them more clearly, but also recognizes that there are obviously different forms.
Source: NASA
And these plates vary actually from MLP to MLP and are themselves neither uniformly on a MLP on all supports, nor on the front and back of individual supports, what can be quite confusing at the moment.
Therefore, I have henceforth concentrated myself only on images from the MLP 2, and there are also supports (the left 18'' outlet) mounted on the top which still have an additional third stiffening plate.
Source: NASA
And these plates I have availed for bonding a filigree frame of a 0,25 x 0,5 mm strip, because without one, though minimal, bearing surface it would be probably become nothing.
For the plates at the base I have cut narrow strips of 0,1 mm Styrene and glued it onto the angle with MEK.
And on these strips, I have glued the frame strip (0,25 x 0,5 mm),
then I've cut the overhanging strips. And then, at the corner followed the first bend and bonding of the frame on the narrow side, etc. all around. 
One just have to pay attention to solid support surfaces, then it will work, even if it is rather fidgety.
After this also the second Support variant with an open bottom was finished and is presented here with the first variant.
Now may be glued even the plates on the back.
And now also the top part with the sickles was glued, thus the support would be completed.
And the fitting of the first support on the MLP should not be missing.
Accordingly, I will stay with this variant, since the envisaged channel variant therefore has become superfluous.
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#961 by Ronpur50 on 05 Jun, 2016 03:25
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If I knew were to find an emoji with it eyes busting out it's head in total amazement, I would post it here!
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#962 by roma847 on 05 Jun, 2016 12:00
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Thanks Ron for your great compliment and excitement.
Maybe this can help ...
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#963 by Ronpur50 on 05 Jun, 2016 12:19
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Thanks Ron for your great compliment and excitement.
Maybe this can help ...
That's it! -
#964 by roma847 on 08 Jun, 2016 17:14
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Hello friends,
as I had already indicated, with the first bend test of the 18'' outlet I was not completely satisfied, because the upper bend downwards to the kink total still was too round what was due to the template.
In reality, the piece above the support is until to the edge of the Blast Shield but straight, as one can see here.
Source: nasatech.net
In the meantime I've also bought Evergreen Rods Ø 3.2mm.
In order to get the bend at the second time right, I have bevelled the slight arc of the template, as well as choosen a different bending sequence and initially bent this kink only, whereby the top piece is straight.
And this straight piece now I have extra strongly fixed, so that it during the subsequent bending of the upper arc also remains straight. That was the whole trick, and this has worked actually.
Then I have tested how this looks in the SRB chamber, and I must say, much better.
Then followed the lower bendings, for which everything was fixed bombproof again,
what was worthwhile,
as becomes clear by comparing the two outlets. The first outlet was downwards even a bit too long, what I have also corrected.
And with this fitting now I'm more than satisfied,
and can finally give rest. And so I will now also scratch the remaining three of these outlets even before then follow the outlets with the tapers.
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#965 by Ronpur50 on 08 Jun, 2016 23:54
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WOW, that made a BIG difference! Awesome!
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#966 by the_other_Doug on 09 Jun, 2016 00:43
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Seconded, Ron. It's amazing what Manfred sees as being "off" that wouldn't ever touch off the average modeler's radar. And, when he gets it to where he's satisfied with it, the improvement then becomes glaringly obvious to us all.
True modeling genius at work. We're privileged that you share your enthusiasm, process and results with us, Manfred. Seriously, as I've said before, your posts are always high points of my day.
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#967 by roma847 on 09 Jun, 2016 13:55
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Thanks Ron and Doug for your agreement and enthusiastic hymn of praise, about which I am very pleased.
But this has left me no peace and I could get no satisfaction, therefore I had to come up with an idea, and in hindsight it was just a small but effective trick.
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#968 by roma847 on 15 Jun, 2016 08:19
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Hello everybody,
meanwhile I have bent into shape the remaining three 18'' outlets and have tried, to make them as congruent as possible. While this is relatively easy with the upper arch using the template,
but the lower bendings are more difficult because of the short distances, because one needs suitable balsa pieces and must clamp them multiply. And then one has to make absolutely sure that one must bend the last bending of the two inner outlets laterally reversed. 
But that looks at least so far not bad. Now only missing the outflow openings, at which I'm still fiddling about.
Then I have prepared two templates for accurate and especially stable positioning of the ring line above the SRB chamber because so far the test fitting of the disposals were pretty stressful, because the ring line is often slipped away from the support dummies.
Now the ring line sits perfectly and relatively stable over the chamber, whereby the fitting of the outlets and later their installation becomes much easier.
Well, and now the outlets between the SRB Supports come into play, which are rejuvenating downward after the top 18'' arc to 12'' (Ø 2 mm).
Source: NASA
This I want to do, by bending the upper arcs according to the template and then the lower angled 2 mm outlet will be attached separately. And this transition is then modeled with Apoxie Sculpt. I think at least that this technique should provide more uniform transitions than with the hot air draw technique. 
And this I try then next time.
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#969 by roma847 on 17 Jun, 2016 23:06
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Hi there,
before I have started with the dimensioning of the parts for the outlet from Ø 3,2 mm to Ø 2,0 mm, I have looked some of the details a little bit closer.
As you can see in the picture, the bends of the outlets are about at the same height,
Source: NASA Street View
and the geometry of the bends seem to be about the same.
Source: NASA
As one can see in this picture, the transition region to the tapering lies approximately over the top of the triangular pipe support, and the vertical 12'' outlet is scratching even at the SRB-Blast Shield.
Source: NASA
And since this outlet is directly running to the shaft wall downwardly, would this 18'' bend actually be somewhat narrower or shorter than the bend of the outlet behind the SRB support with no taper. Accordingly, the pipe supports should be about the same size, I guess.
And this outlet I have now composed of two parts. The shape of the upper bend (Ø 3.2 mm) is identical to that of the previous outlets and was cut off at the point above the triangular support. And then the angled part of the taper was attached (Ø 2,0 mm), whose transition still will be modeled with Apoxie Sculpt.
The picture shows also the first attempt to indicate the outflow opening at the end of the pipe.
Source: NASA
For this I have drilled out the 2 mm rod below with Ø 1,6 mm and removed one half of the "tube". The resulting opening becomes still beveled and closed downwards with a small disc. And I mean that one can definitely accept it, right?
And this is now the test fitting of the tapered outlet at the ring line. But as one can see, unfortunately, does not fit properly so, which indeed would be too good.
The upper 18'' bend protrudes too far inwards, whereby the support does not fit under the 12'' outlet, which also is not snug enough on the shaft wall. That's why I have to shorten the inside of the bend a little bit, whereby the outlet is coming closer to the shaft wall. Thereby the support also should fit better under the tapered part, I hope at least.
So I have further experimented and both the 18'' bend as well the 12'' outlet slightly shortened.
And this is the preliminary result. The outlet has thereby indeed moved a bit closer to the shaft wall,
but the bend protrudes still too far inwards, whereby the clearance for the support is still not enough.
Therefore, the arc must be estimated shortened by 1 mm, then it possibly could fit better.
Step by step one gets closer ...
Here is the result after the shortening of the bend.
And lo and behold, now the support fits better.
At the front outlet this support inevitably is missing now, whereby this is not fixed properly and logically sagged down too much.
Thanks for watching and bye for now.
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#970 by Bubbinski on 20 Jun, 2016 01:34
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This is one of the "highlight" threads of the NSF.com forums. Keep going Manfred, that is some highly detailed work on a highly complex structure.
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#971 by roma847 on 20 Jun, 2016 08:17
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Thanks Bubbinski for your great praise
that inspires me to keep going. 
You know what you are talking, this is really an improbable complex project that costs a lot of time at this level of detail.
But these crazy details challenge me again and again, I cannot help myself and can't let go.
Thanks for watcing and stay tuned my friend.
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#972 by roma847 on 23 Jun, 2016 15:27
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Hello everybody,
if one looks at this 12'' outlet more closely, one sees that it is still too much rounded at the kink,
which is why I have this pronounced even stronger, as can be seen right in the picture.
And from these outlets I need a total of six pieces that I need to scratch now.
Since the 18'' arcs of these tapered outlets but are slightly narrower than those of the other four 18'' outlets without taper, I had to create a new Balsa template for bending.
For further handling, it was skillful, initially to file the rounding at the left end of the arc and only then to remove the right end of the arc.
How now shows the test fitting in the next picture, the new arc is but still a bit too long and still needs to be shortened somewhat, so that the outlet comes closer to the shaft wall.
And then I have tried to also represent the outflow opening opened at the 18'' outlets, whereto I drilled the end with Ø 2.5 mm and sanded a bit at the inside.
Then I have heated the opening and pressed together in the sliding caliper.
And this opening really appeals to me actually completely well,
especially as it looks more realistic than the first attempt.
Maybe I'll find even a slightly larger drill to reduce the wall thickness a bit more without having to smooth the opening yet.
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#973 by roma847 on 25 Jun, 2016 12:03
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Hello everybody,
after the first training, I have now begun to scratch the six outlets with the taper from 18'' to 12'', which consist of two parts.
Thereto at first I have bent the 18'' arcs with my new Balsa template, and then the simple angles of the 12'' outlets. The shortening of the arcs happened initially based on my sketch, but the comparison of the arcs showed slight differences in width.
So I had to be little more exactly when shortening the arches, wherefore this upper stop was helpful. So the position of the arc is clearly fixed, and the shortening always happened in the same place, which has thus delivered same lengths.
Thereby the 12'' outlets could be precisely measured and shortened, which in turn shows how important it is a defined stop.
And finally, still the test arrangement of this modified outlet, here still in the wrong place in front of the SRB support, but not too disruptive in this case. But it is just clearer than on the back of the support. 
And so now to the outlet opening at the bottom that I had already tried.
Source: NASA
The 2 mm (12'') rod I have drilled below with Ø 1,5 mm, have cut the opening and bevelled, and then glued a disc with Ø 2.5 mm as a final deflector. And then there's still this little protective plate, which I've rounded from 0.1 mm styrene.
And then finally it looks like this,
and would be the outlet at this point, whereby the outlet opening is obscured however here.
Source: NASA
Thanks for watching.
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#974 by roma847 on 29 Jun, 2016 21:54
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Hello friends,
in the meantime I have begun with the production of the six 18''/12'' outlets.
The remaining two inner outlets differ from those six thereby that they directly rejuvenate from the 24'' ring line to 12'' and they have a special shape that I have to bend separately.
Source: NASA
After I have slightly shortened and equalized all the arcs (3.2 mm Ø) one more time, now the outlets (Ø 2.0 mm) had to be drilled by hand at the bottom with Ø 1.5 mm for the outlet openings.
To drill the holes halfway centered, one has to go step by step and can not immediately start with the final 1.5 mm drill. Therefore, the center initially had to be center-punched as accurately as possible, because the drill otherwise runs eccentrically at the slightest deviation. 
After that followed three bores, first with Ø 0,8 mm
and 1,2 mm,
and only then with Ø 1,5 mm.
Then the openings were cut in half with a razor blade. In doing so it is advisable to leave the blade in the cut and to cut on this the half opening with a second blade to not equal to cut off the entire opening, what has happened to me at the first time.
Thereby one has to take into account the different inclined position of the outlet openings towards the SRB center, which is marked in this image for the left SRB chamber behind the LH2 TSM. Thereby the outlets 1 and 3 are identical, and outlet 2 is the outlet with the special bending which was shown at the beginning. 
Source: NASA
And these are the items for the outlets, left in the image the identical outlets 1 and 3 and the outlet 4 for the left chamber and right the outlets for the right chamber behind the LOX TSM.
Underneath lay the discs (Ø 2,5 mm) for the deflector plates and next to them the fenders (3 mm x 4 mm), which are to be rounded from 0.1mm styrene, and the strip (0.25 mm x 0, 5 mm) for the retaining strips.
Next will follow the installation of outlets.
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#975 by roma847 on 30 Jun, 2016 06:31
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Hello everybody,
and now a few pics of the assembly of these outlets.
First, I have glued the rounded little fenders with the fixing rail at the end of the outlets, and then the small baffles.
what went relatively quick.
Subsequently the arcs were glued with the outlets.
For exact alignment of the arrangement my little jig was very helpful again.
And that's it for today already.
Now only the tapers at the transitions have to be modeled with Apoxie Sculpt.
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#976 by roma847 on 03 Jul, 2016 15:14
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Hello everybody,
the modeling of the tapers at the transitions of the outlets still can wait a bit, because the last two 12'' outlets on the front insides of the ring lines are still missing and differ from the previous six outlets. They taper directly from the 24'' ring line to 12'' (Ø 2.0 mm) and have themselves no further taper, but a tortuous curved course, as can be seen here once again.
Source: NASA
As the trained eye can recognize in this picture, the upper bow however is more flattened than the two rounded outlets left besides and is also a little lower, what can be seen clearly in particular in this perspective (green arrow).
Source: NASA
In contrast, the bows of the outlets on the outside of the ring line lie all at the same heights level and are clearly rounded.
And that immediately raises the question of the dimensioning of these two outlets, wherein the difference in height is more important than the shape which can be modified from the previous rounding.
For estimation of the height difference I made the following contemplation in the penultimate image, whereby I have used the diameter 4.0 mm of the ring line as reference (yellow). Based on the alignments of the ring line and the two 18'' bows the supernatant (red) is about 2.4 mm.
Source: NASA
Since the supernatant of the flat 12'' bow (green) results to about 1.4 mm, the height difference should be about 1 mm, which is not much, but still present.
And because a new Balsa template was required for this transition, it went with this in a proven way back to my Balsa bending bench.
And this is the preliminary result, whereby the flattened part of the bow but still seems to be a little too wide.
That's why I wanted to bend the left bow still somewhat narrower, however without heating, which has unfortunately led to an unexpected fraction, although I was carefully.
But every now and then I have to learn the hard way too. Apparently, the plastic loses during the hot air bending its ductility and becomes brittle, which one just only needs to know, but adversity is the school of wisdom. Nobody is perfect.
Therefore here a picture of re-glued and slightly modified bow, which still had to become slightly narrower.
And only when this bow fits, it will go on with the tortuous transition to the ring line.
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#977 by BrightLight on 03 Jul, 2016 19:54
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You make even the most mundane parts works of art, I feel fortunate to see your progress - Bravo!.
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#978 by Davp99 on 03 Jul, 2016 20:27
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I Know Bright Lights, He is a Master and I feel Humbled to get to see his workings..
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#979 by roma847 on 03 Jul, 2016 22:34
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Thanks Guys,
I am glad that you like my work, Daniel, and I will try to keep it that way.
But you must be kidding, Dave! Heads up! Don't worry, be happy.
