Space Shuttle Launch Pad 39A with Challenger STS-6

[roma847]

Hello everybody,

 

a friend of our Raumcon-Forum has sent me a small roll of silver adhesive foil for testing.  

 

 

The foil is so thin that one can hardly measure its thickness (about 0.03 mm), and was of course tried the same time, for which I have cut small 1 mm wide strips with a brand-new cutter knife. 

 

 

 

which I then glued tentatively onto an Airfix Aft Skirt-Ring, which seems to be a practicable solution.

 

 

Then I also glued three of these foil strips on the half pipe (right). 

 

 

And finally respectively 24 strips must be glued onto the 3D printed and painted ASTC Rings, which might be a bit of fiddling, but should be feasible.  

[RichO]

The foil experiment looks good!  ' hope it works out well for you.

[roma847]

Thanks Rich,

 

but the surprise had not be long in coming. 

[roma847]

Hello together,

 

well, I was rather amazed when I suddenly saw at noon today that the adhesive film strips had detached again from the rounding of the half pipe.

 

 

Apparently, the adhesive film has certain residual stresses inside, which exceed the adhesive force of the strip after a certain time and lead to detachment.  

 

This can be seen on this piece of adhesive foil, which bulges itself to the silver side after cutting from the roll. 

 

 

A similar effect I noticed every now and then on some of the glued strip ends, which did not glue firmly enough and stood out a bit (≤ 1 mm), which I then again had to glue with MEK, and a very unruly end with CA.  

 

The household foil does not have these internal stresses, which is why their strips are still firmly fixed, furthermore they were glued with MEK respectively CA.

 

However, I have to say in hindsight that I had not degreased the half pipe before gluing the adhesive foil strips, which could be the reason, what I will check again tomorrow.  

 

Then I had also ordered a Chrome marker (1 mm) at Rai-Ro, which arrived today, which of course I tried out right away. 

 

Around these markers of Molotow a real hype has arisen, whose highly pigmented special ink creates a real mirror effect on smooth, non-absorbent surfaces.  

 

At first, however, I could not cope with the marker because I did not know that it was a Pumpmarker, which had to be shaken and briefly pumped before use.  

 

While straight lines drawn with ruler are not a problem, using the marker on the half tube was a bit more difficult and definitely needs getting used to, which certainly requires some practice.

 

Therefore, the first six strips on the right end are certainly not optimal, but at least a ray of hope.   

 

 

So much for the insights from my experiments today.  

[John_W]

Have you considered warming the tape? Might soften the adhesive and make it conform to the curvature.

[roma847]

Thanks John, this is also a good advice,  I have heeded, which unfortunately brought no positive effect too.

 

Hello friends,

 

I have also still tried something else.

 

At first, I degreased the half-tube with Isopropyl and then glued three new adhesive foil strips.

 

In order to check a possible diameter influence, I also put a strip on my thick Rainbird knitting needle (Ø 8 mm), and lo and behold, there it still glues always firmly, without any signs of detachment, which seems to confirm my guess.

 

On the other hand, on the thinner half-tube (Ø 4,7 mm) after a short while the ends began detaching again, what can be prevented however by fixing the ends with CA.

 

 

Then I've made another attempt with the Chrome marker, for which I taped a 1 mm wide strip  on the half-tube on both sides with tape (2 mm) and then painted this area by using the chrome marker simply by hand. But after removing the tape strips one can see that the chrome line is still not even, because the liquid partially creeps ugly under the tape. 

 

Besides, this procedure would be pure stress at 24 strips per Aft Skirt ring, except from the fact that the marked strips probably would not have the same width at the end anyway.

 

 

But now we will wait for the delivery of the 3D-ASTC prints, which I have now also ordered in Frosted Extreme Detail (FED).

[RichO]

11 hours ago, roma847 said:

Apparently, the adhesive film has certain residual stresses inside, which exceed the adhesive force of the strip after a certain time and lead to detachment.  

You sound like a Material Anallysis Phd.

[roma847]

Hi Rich,

 

nearly you hit the nail on the head, my earlier profession was Materials Research or also Material Science. 

[Mustermark]

Haha. That's funny. At least you have experience to help you in this task. My PhD in Biochemistry is not so relevant to my model hobby 🤣

[roma847]

Hi Mark,

and welcome for another Doctor of Science. 

Yep, that's why I'm interested in such material and technological aspects, which is very helpful, and that's also the reason, why I always want to get to the bottom of things. 

[The Chief Smeg]

12 hours ago, roma847 said:

get to the bottom of things. 

Isn’t that a Proctologist?

 

well, my background is mechanical engineering (aerospace) and I am finding all of your build absolutely fascinating!

[roma847]

Thanks for your compliment, 

 

but sorry, what gives you that idea - Proctologist? 

[The Chief Smeg]

It was a very poor pun on you saying you get to the bottom of things...

 

...I’ll get my coat.

[roma847]

Well roared, lion! 

 

I'll say hello to my Google translator with best wishes from you. 

 

BTW, be careful not to forget your hat! 

[roma847]

Hello together,

 

as I've heard it from other guys in ARC Forums, Bare-Metal Foil should be working well, but there are different Chrome Foils, e.g. 

 

Bare-Metal Foil - Ultrabright Chrome

 

and more recently also

 

Bare-Metal Foil - New Improved Chrome, whereas this foil would be a little thinner.

 

At first, I wanted to decide for the Ultrabright Chrome, but then they discouraged me from this kind and recommended the New Improved Chrome, which would actually be thinner and, as a result, better cling to fine contours and details and stick more tightly.

 

That's why I have ordered this chrome foil now and will test it for making the ASTC stripes.

 

Does anybody have experiences with it?

[xffw45343tg]

Hi Manfred.

 

You're going to have to have words with Google translate about "Hello together".

We all know what you mean - but it's not anything that anyone other than a Googlebot would say. I assume it is translating something like "Hallo zusammen"? You'd just say "Hello everyone." or "Hello all." or "Hello everybody".

 

But forget all that. Just more launch pad please - when you're ready.

 

Kirk

PS/ I have used a bit of Bare-Metal foil in the past but can't offer anything useful in answer to your question. It was thin and sticky enough for what I was trying to do.

[roma847]

Thanks for your kind tutoring,

 

and when you all know what I mean, then it's okay. 

 

Only if Google translate suggests formulations that you no longer understand, we would have a problem. 

 

Therefore, make a simple try and translate your answer into German, then I could say if and how well I understand you. 

But as you rightly say, let's forget all that. 

 

But if you've already processed Bare-Metal Foil, how good has it been to cut, since it's very thin? 

 

As you know, I have to cut thin 1 mm wide strips that should have smooth edges without to wrinkle. 

[xffw45343tg]

My recollection is that a sharp scalpel gave a good edge - although (because the foil is metal) it may distort slightly at the cut edge if the cutting mat is slightly soft. Not a problem for a him-fisted modeller like me (the edge just burnishes flat after placement) but I don't work to the nanometer tolerances that you do.

 

Since you have a sheet on order, I'm confident that your materials test programme will be far more useful than any recommendation I could give.

 

Kirk

PS/ Don't get me started on translation software. Much better than nothing but much worse than the human mind. I certainly wouldn't trust it to launch a spacecraft.

[roma847]

Thanks Kirk,

 

today I've received the foil, and so I can test it. 

 

But at first glance, the foil does not look as mirror-like as aluminum household foil. 

 

[roma847]

Hello everybody,

 

here you can see my comparison test,

 

from left to right:

 

Aluminum household foil - Bare-metal foil (New Improved Chrome) - Silver party streamer. 

 

 

BTW, I had smoothed the Bare-metal foil strip several times with a Q-tip in the hope that it would shine more, but unfortunately without a significant effect.

 

And here in comparison with the party streamer and the silver foil of my Raumcon friend on top of the Bare-Metal foil, which looks relatively matt gloss,

 

 

which is not mirror-like for my taste, although the lighting always plays an important role.

 

[roma847]

Hello everybody,

 

the last few days there was still a nice surprise, because the featherweight package of Shapeways with the AFTCs has arrived,

 

 

and was very carefully unpacked, after all, it's my first, but certainly not my last.  

 

The Thanksgiving card made me even more curious.

 

 

At the first glance, everything was packed very well.

 

 

At first I was surprised by the number of bags , especially since I had ordered both versions, FUD and FXD, so four rings.

 

 

But now it's time for dinner,
see you later, and stay curious my friends ...  

[RichO]

Cruel shoes, Manfred!

[roma847]

Hi Rich,  ...  ...

 

Hi friends,

 

and here are the AFTSs, where one can hardly distinguish the two kinds with the naked eye, to the left the FUDs, and to the right the FXDs.

 

 

Of course, they now have to be freed from the rest of the supporting wax necessary for printing before they come fully into their own.

 

 

Only at higher magnification one can recognize the dividing lines between the individual segments, whereby the surface of the finer-grained structure of the FXD (right) feels a bit finer. 

 

 

But of the feared and often described stepped structure of 3D prints is no trace, which has pleasantly surprised me.  

 

 

And as one can see, the ring fits perfectly in the SRB Aft Skirt, 

 

 

as well as the nozzle into the ring, which proves that I must have measured well and the parts have been printed exactly.

 

 

And so I really like the 3D AFTC Ring much more better than the spartan part of the Airfix Kit, to whom the Revell ASTC comes relatively close. 

 

 

I suspect that the dividing lines between the segments should become even more visible after cleaning and can still be seen after painting, so that the silver foil insulation strips can still be glued on well.

[roma847]

Hello everybody,

 

quickly a small addendum to the ASTCs, which are tailor-made for the Airfix Shuttle Stack (1/144).

 

But one can use them also for the Revell Stack, as one can see on this image.

 

 

Since the inner diameter of the Revell Aft Skirts is slightly larger than for Airfix, it might therefore be advisable to glue an Evergreen Strip 0,25 mm x 1,0 mm around the ASTC ring. Then the ring would probably fit even better.

 

Or I could ask my ARC friend and 3D modeler Joe (crackerjazz) if he could enlarge the ASTC rings for the Revel Kit to Ø 33,5 mm.

 

And finally, the still remaining test with the Bare-Metal Foil (New Improved Chrome), of which still 24 thin strips (1 mm) must be glued after the painting of the rings, for what a lot of patience should be necessary again.

 

For this I have cut a longer 1 mm wide strip. Then the very thin film can be easily removed from the carrier strip, then each short pieces of it were cut off, 

 

 

and glued to the half tube (to the left of the green line) as well as onto the Airfix ring and pressed and smoothed with a Q-Tip. These are the two stripes to the right of the Liquid Chrome strip that I have recently applied with the Pumpmarker.
 

 

And as one can see, the Bare-Metal Foil is sticking firmly even still after some hours. Let's see what it tomorrow will look like, hopefully not as with some of the previous stripes, but rather still unchanged firm, wherefore I precautionally press both thumbs.

 

And the chrome luster of the stripes is in my opinion completely sufficient, so that I would be fully satisfied with this result, if it stayed so.

[RichO]

Hi Manfred,

 

  "Cruel Shoes"  a local term meaning - to build up anticipation for something, and then not satisfy. 

 

   The FUD ring looks to be somewhat transparent in nature next to the FXD ring.  However no worries when it all comes back from the Pain Dept.  The step texture used to much more prominent with earlier printing machines, but of course, things improve.  The first items I received from Shapeways a few years ago had a visible/sensible surface. Not so much these days.  I hope your foil works out ok.