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Hi guys .

 

Sorry but my question wasn't innocent :D. I read on others forum some modelers has problem with hangs paint , a reaction between the paint and the resin

Acrylic resins (Shapeways) must be cooked at the end of the process using a "bath" of ultraviolet rays ,but often parts remain incompletely treated for lack of time or care by the manufacturer .

 

The best way is a UV oven to finish the process and eliminated the bad surprise .You can make a oven with a few euros : a UV led ribbon  (400 nanometers minimum) , a connecting cable , transformer 12V 4A and a blanket (for reflect the UV light Inside the box)

 

Pierre

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Hello everybody,

 

Shapeways' shipping did not take so long, if you have been wondering about the send pause.  top.gif

 

The reasons for that I still want to explain before the holidays, but the devil is often in the detail, or better said in this case in the Shapeways' tolerances, which I have not yet known so far. rolleyes.gif

 

And if one or the other in the mean time has clicked on the link of the SW website in my Reply #1413 then he will has been surprised. Oops!!! shocked.gif

 

Outwardly, the second Intertank looks really great,  speak_cool.gif 

 

xhSk5m.jpg

 

but already the test fitting of the ET front part was not possible because the connection diameter D2.1 was still slightly larger than that of the first IT, namely instead of 53,5 mm it was now even 54,1 mm. You could have knocked me down with a feather!!!  eek.gif

 

up062050.jpg

 

Instead of getting a little smaller by Michael Key's adjustment for a better matching the Airfix IT-values, the dimensions became in spite of taking shrinkage (0,8%) into account amazingly even a bit larger, which is still mystery to me. smiley_worship.gif

 

This is shown by the comparison of the dimensions of the two ITs with the Airfix-IT,

 

o2kLb4.jpg

 

whereby I've tried to measure as accurately as possible. cant-believe-my-eyes-smiley-emoticon.gif

 

GLdkQN.jpg

 

SXHBAF.jpg

 

cWskgG.jpg

 

D45sel.jpg

 

While the larger length is less a problem for the fit of the parts, rolleyes.gif

 

mcxduc.jpg

 

the resulting diameters all the more so as the overall IT was printed too large, which can also be seen at the back overhang of the IT, which is just too big for me. erschrocken3.gif

 

uVYmTO.jpg

 

Of course, Michael Key was also very surprised, because according to the SW website, the visible length of the IT (without front connecting ring) should be around 48,9 mm (48,5 mm x 1.008 shrinkage), as it was indicated in his CAD file. 

 

He then removed his shop offer rolleyes.gif and contacted Shapeways for anew refund, which I've received in the meantime. cool.gif

 

While the tolerance for FUD on the SW website is indicated with

 

Accuracy ± 0,1 - 0,2 mm for every 100 mm

 

we have now been told that the actual tolerance of the material is up to 0,4 mm, so one can not guarantee that the IT is perfectly sized, which is inconsistent and in my opinion difficult to accept it. hmmm.gif 

 

However, in a sketch by Michael Key with all dimensions of his CAD model without and with shrinkage (0.8%), I discovered a small flaw that may have contributed to the enlarged diameters, which he has now corrected. huh.gif

 

With these last changes, he has uploaded the model again, and here it can be found. 

 

Now he will also upload a WSF version, which does not have to consider shrinkage and which will surely become a bit cheaper. up040577.gif

 

Now I'm curious what kind of egg this time Shapeways will put into the nest me.  smiley215.gif
Otherwise, I wish you all ostern027.gif and thank you for looking in on me.

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  0.4mm is a big gap Manfred.  For the price you are paying for this item you should get the tolerances quit a bit closer.  I hope everything works out finally in the end for this great build.  I know it will tho.

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Hi Rich,

 

I fully agree with you, normally it is absolutely a No go!!! It is unacceptable for the customers that SW simply declares new tolerances that are twice as large if the specified limits are not met. up043952.gif

 

And therefore I will inform SW that I'm expecting their guaranteed FUD accuracy of 0,1 - 0,2 mm for every 100 mm for the proud price of this print. schlaumeier.gif

 

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  • 2 weeks later...

Hello everybody,

 

today with a short update from the Shapeways Team. cool.gif

 

I just could not stand for this contradiction regarding the FUD tolerances i5684_no2.gif and I asked the friendly Shapeways lady, who initially wanted to give me only a lapidary, meaningless answer boese.gif, to explain this dilemma to me. schlaumeier.gif

 

Thereupon was it confirmed by a production colleague that the maximum accuracy that SW can achieve at FUD is actually 0,4 mm, and that the SW guidelines should be adapted, to what one would now work on. rolleyes.gif

 

Well at least something for which my effort has been worthwhile, although still to this day one finds the unchanged previous precision specification of ± 0,1 - 0,2 mm for every 100 mm ... up035091.gif

 

Meanwhile, the third IT is on its way to me, and I'm curious what it will look like. top.gif 

 

In the meantime, I've looked around a bit on the SW pages and now I can better imagine the matter with the Support wax, whereto I have found this nice image at the end of the FUD website with the following explanation. 

 

6XGnyw.jpg
Source: www.shapeways.com/materials/frosted-detail-plastic 

 

And remnants of this stuff one has still to remove off afterwards from the printed parts, although the cleaning at SW actually belongs to the standard procedure, but what is apparently not quite enough. smiley_worship.gif

 

On this site you will also find an interesting Video in which the individual steps of the multi-stage production process are clearly presented by a SW production engineer.  up045518.gif

 

After printing, the models are placed in a freezer to help detaching the parts, and then into an oven, where the wax base melts. Then they are placed first in an ultrasonic oil bath and subsequently in an ultrasonic water bath to remove residual wax and oil residues, and finally, after thorough water rinsing, they are dried and finally tested.

 

Here is an image of the second IT, which looked a bit cleaner than the first one. 

 

QC3LYF.jpg

 

The traces of grease on the paper show, that remnants of the wax/oil remains for the customer unfortunately,  rolleyes.gif

 

xGaSxw.jpg

 

4zv24D.jpg

 

here during the sunbath of the two ITs for the allegedly necessary complete curing of uncured microscopic resin areas under UV light, which was proposed by a shapeways designer named Model Monkey, who is presenting some useful tips (FAQs) on how to use Shapeways prints.  up040577.gif

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Hey everyone,

 

meanwhile, I have received the third IT, which makes a much better figure than the first two,

 

zUusuN.jpg

 

and fits also better between the two ET parts, as one can see here. up045518.gif

 

vJq8Fz.jpg

 

M8yeoo.jpg
 
And here the LOX Feedline from the Revell Stack was laid down experimentally. cool.gif

 

RjjC4F.jpg

 

As my remeasurement has shown, but no shrinkage seems to have occurred, so one would probably get along without the 0.8% addition.  hmmm.gif 

 

Then I started with the tests for ultrasonic cleaning of the IT, for what I used the 2nd IT. To grope me step by step to the required cleaning time, I have each set the longest interval (600 sec.), which was repeated several times in succession. huh.gif

 

First, I put the IT on the rear end and cleaned it in from this side a total of 30 minutes, with about 80% were immersed.

 

GWI1OD.jpg

 

jmDajj.jpg

 

yIErVn.jpg

 

After this first cycle, the water looked rather cloudy, rolleyes.gif

 

B55LCV.jpg

 

and was therefore renewed for the cleaning of the other side, which then also took 30 min..

 

After that the IT looked like this, whereby one could see at a closer look but still wax residues in the grooves,  cant-believe-my-eyes-smiley-emoticon.gif which is why half an hour apparently was not enough.

 

qYhzyd.jpg

 

Therefore, I helped along with the electric toothbrush under running water, because the fine grooves between the stringers are obviously the purest wax catchers, which I had already feared. smiley_worship.gif

 

But since even after this action still small wax remains were to be seen, then I grabbed the cutter and went on carefully further cleaning out the interspaces, which is also quite effective, as can be seen at the stripped off residues on my thumb, 

 

1JJjWz.jpg

 

as well as at the cutter tip. undecided.gif

 

ry05O2.jpg

 

This stuff seems to sit so firmly in the grooves, so one will need much longer cleaning times in the ultrasonic bath, as initially suspected. eek.gif 

 

Therefore, I've added another pass of 30 min., which now gives a total cleaning time of 1 h, after which the water is always still cloudy.   

 

Y3n457.jpg 

But as one can see at these photos, there are still areas with more or less wax residue. smiley215.gif

 

VA2eDD.jpg

 

m1U4OT.jpg

 

UQJEau.jpg

 

That immediately reminded me again of the 3-4 h cleaning time in the  BANDELIN-Video during cleaning a FUD chain ... omgsign.gif

So I will either extend the cleaning time still significantly, or sometimes have to try Aceton, or are there any ideas of the Shapeways experts here in the forum?  up047089.gif

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Nice video Manfred.  Be careful the Aceton dose not melt the plastic you are working with.

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  The Crawler treads were so clean when I received them, I just used soapy water to clean them.  Your piece seems to have a lot of thin fins to catch everything used for support.  Try using a stiff tooth brush for the small areas.  Good Luck!

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Hello everybody,

 

following a hint in our German Raumcon Forum, I looked in my Dremel accessories and also found a Nylon Rotor Brush and a Nylon Brush, which I have immediately tested at medium speed. cool.gif

 

stZkfH.jpg

 

In addition to the disadvantage of the many fine grooves, the Intertank has the advantage that it has no protruding small details that can easily break off when brushing, and also it is quite robust. up045518.gif

 

zgouoN.jpg

 

That's why I was able to ride across the grooves relatively easily and smoothly with the rotor brush, whereby it was already visible to the naked eye how the white wax residues gradually disappeared and the grooves slowly became clean, which pleasantly surprised me. top.gif

 

WXwUxD.jpg

 

While cleaning in the area of the Stringer Panel is relatively easy due to the continuous grooves,

 

F14SKl.jpg

 

one has to do one's best in the subdivided areas of the Thrust Panel. rolleyes.gif

 

OwInt6.jpg

 

Under the big magnifying glass, one can see more clearly the differences between areas with wax residue and already cleaned areas. spiegel-smilies-0002.gif

 

And furthermore one can still see that in the two outer areas of the Thrust Panel on the right edge with the little "pockets" still sits a lot of wax, because they are worse reachable with the Rotor brush, which is why I there will try the Nylon brush that will probably get in better there. smiley215.gif

 

qcjzWV.jpg

 

To be able to see such differences in detail even better, cant-believe-my-eyes-smiley-emoticon.gif I always apply the following trick.

 

To do this, I paste the photo into a Word document, then I increase the magnification, as shown here e.g. up to 300%, and take a screenshot, which I then upload.  up045518.gif

 

This closeness can no longer be captured by the autofocus of my digicam.  i5684_no2.gif

 

AKFs7I.jpg

 

This is the maximum possible closeness, if the image is still to become halfway sharp. huh.gif

 

OEwva2.jpg

 

And here I've tested the Nylon brush, and I have to say that does not look too bad. speak_cool.gif

 

j6TZOt.jpg

 

The cleaned area stands out clearly from the rest of the area, whereby one must consider that this IT was already 1 h in the ultrasonic bath. hmmm.gif 

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What a great idea with the photos!  That will come in very useful.  And nice save with the brushes.  The piece looks nice and fresh.

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Thanks Rich,

 

meanwhile there are other possibilities as I have learned, like this Clip-On Microscope Magnifier Universal Lens with LED/UV Lights for iPhone 7 6s 6, Samsung, LG and More Smartphones


https://www.youtube.com/watch?v=t3bXWcY2khI

 

Nothing is impossible, that also seems to be a useful thing that one should try once ... up040577.gif

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Hey everyone,

 

BTW, an interesting suggestion came from another modeler, after what I should put the IT completely in warm water with a few drops of detergent overnight, about 8 to 10 h. This time should be sufficient for the detergent to soften the bond between the wax and the FUD. Thereafter, the IT should be put into the ultrasonic cleaner to finally detach the residual wax. smiley215.gif

This "Long pre-soak" Method is known to be used in industry for quite a number of cleaning processes. 

 

This Intertank with its many fine grooves seems to be a prime example of a "wax catcher" analintruder.gif and therefore obviously needs a combined special cleaning treatment. 
But I  will not let up until I have found a way out, rely on it. up040577.gif

Therefore I'm going to try the Pre-soak method (maybe a day or two) with my 1st IT, whereby it actually seems logical that soaked "dirt" can be removed better, as in grandmother's time ... top.gif
And maybe the brushing out of the grooves with the Dremel brush can also be done under water. smiley232.gif

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  • 2 weeks later...

Hello everybody,

 

the more one deals with the problem of cleaning of FUD-prints, the more partially contradictory opinions can be found, especially regarding the use of Acetone. rolleyes.gif 

 

While this substance is recommended by Shapeways itself, analintruder.gif how has been previously shown,

 

bvlB4C.jpg

 

other users advise against it categorically, or warn of danger, such as Model Monkey,  nono.gif

 

It is all the more astonishing that at Shapeways no more precise information on the application (time, temperature, etc.) let found, wherewith they oversimplify the matter themself, because quite so easy, as one writes, it is not. i5684_no2.gif

 

That's why I did a test with Acetone.

 

Without thinking of something bad, I have put the 2nd IT into the ultrasonic bath, poured in my bottle of Acetone (250 ml) and turned on the timer, followed by a rather violent reaction, and the bubbling acetone became quickly milky-cloudy, which rather surprised me. smiley215.gif 

 

When lifting the IT in the bath, I noticed a slight sticking to the floor, but which could be solved. But since the reaction has unsettled me a bit, I switched off the timer after about 3 minutes and put the IT in a water bath. huh.gif

 

While the FUD surface seems to be slightly roughened, 

 

f6n9Gu.jpg 

 

at the sight of the basket, I was somewhat startled, who had suffered quite a bit, as one can easily see. eek.gif

 

6gdFeV.jpg

 

I should have preferred to remove it before, up040472.gif but afterwards one is always getting smarter. rolleyes.gif

 

Now still a current message, meanwhile Michael Key also has uploaded an IT-Version in White Strong & Flexible (WSF) without shrinkage allowance, which with € 36,22 is much cheaper. up045518.gif

 

DmvYsc.jpg

 

mrxe8T.jpg

 

Fy5Y3g.jpg

 

8YJcYt.jpg

 

So far for today. up040577.gif

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The slightly roughened might be the dissolved plastic from the melted basket sticking to the FUD part.  Check that closely.  Much more luck with the WSF part if you order that!

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I'm not sure, Rich, 

 

if one compares these two images, I rather think, that FUD is superficially slightly solvated by the Acetone. smiley215.gif

 

To the left only cleaned with detergent, to the right with the basket killer Acetone.  

 

HMsRAJ.jpg

 

But there are also opposite opinions on the effect of Acetone on FUD as in this impressive contribution Investigating the use of acetone to clean models printed in Frosted Ultra Detail Material by Dave Yale, which I found in the Shapeways Thread Best way to clean frosted ultra detail model for painting?, who has soaked these FUD tables in each case 10 - 20 - 30 - 40 - 50 minutes and longer in Acetone and then examined,

 

acetone03.jpg

 

after which one FUD table only got soft "knees" after 2 h!!!

 

fudtl-01.jpg

 

And here another strange effect is described by Steve Larsen (Model Monkey) et al. in Powder Appearing On Fud After Storage, what one can see on this ship model of one of his customers. cant-believe-my-eyes-smiley-emoticon.gif

 

crystals-jpg.187133

 

He had used Tamiya acrylic paint which was diluted with Methylethylketone (MEK), what seems to have been the cause of the observed incompatibility with the FUD parts and led to these unpleasant phenomena. eek.gif 

 

Therefore, when cleaning my final Intertank, I will keep my hands off this Acetone and use only the gentler method of detergent/soapy solution, which I could see up close in action last week in the dental lab of my dentist, including post-treatment on more professional equipment, but more about that next time. up040577.gif

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Hi friends,

over the weekend I took advantage of the bomb weather and bathed the final Intertank in the sun for half a day. smiley_shining.gif

 

FHwMDG.jpg

 

RP6m22.jpg

 

QkYWtz.jpg

 

Thereby not completely 'exposed' FUD/FXD should cure, which makes it easier to remove the wax. up040577.gif

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Hello everybody,

 

here's my report on my flying visit to the Dental lab last week. cool.gif

 

At my penultimate dentist appointment, I came up with the idea to confront my doctor with my Intertank cleaning problem and to ask if I could not even consult his colleagues in the neighboring dental laboratory. undecided.gif And friendly as he is, he agreed immediately and said that I should just bring along the tank at the next appointment. speak_cool.gif

 

Said done, before my appointment last week, I was in the lab next door and I just happened to get to the nice manager, whom I showed me the original tank on a shuttle photo of the STS-6 and pressed him the Intertank in the hand, together with a short briefing to my previous chin-ups in the ultrasonic cleaning and the necessary parameters, i.e. mild medium (no Acetone!) and about 50°C. top.gif

 

After the impression for an inlay I went back in the lab to the dental technicians 'with bite', as the name ChiliDent suggests already.  up045518.gif  

 

This is the manager, Benjamin Geyer, and next to him on the wall stands a Sonorex high performance ultrasonic bath (Bandelin) with integrated heating.  

 

In this bath, he cleaned the IT in soapy water at approx. 50-60°C for approx. 15 minutes, whereby he carried out several visual inspections in between and  brushed off the detached wax particles.

 

BzxxSd.jpgJoXTTJ.jpg

 

Individual areas with remaining wax residues can then be removed in this Reitel Blast cabin, whereby finest glass beads (50 μm) are used. up045518.gif

 

oWCgtz.jpgKFa6PM.jpg

 

And then the IT can still be thoroughly rinsed with a high-pressure water jet. 

 

G7OnEv.jpgNGMM14.jpg

 

That's how I imagine the cleaning of the final IT for which I have already made a date. These are, of course, exclusive opportunities that I do not have at home and therefore thankfully like to use.

 

One simply just must have a bit luck! up040577.gif

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Hello Mark,

 

that's right, and I am also very happy that I can use this opportunity. top.gif

 

But when you look closely, you can see that there are still areas with wax residuals left behind, which shows that the first cleaning was not intense enough, which is why I at home have thrusted them out of the grooves with the steel ruler. cool.gif

 

up062699.jpg

 

0t2fZh.jpg

 

Completely without local mechanical post-processing of these fine grooves, it does not seem to work, or one has to invest more time and care in the ultrasonic cleaning before. up040577.gif

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Manfred that is a very, very thorough approach you've taken.

 

I wonder if, following your dentists experiment, firing pure water through an airbrush with a fine tip might help?

 

It seems that you need some mechanical force after any treatment in a cleaning bath, and an airbrush and water is in most modeller's arsenals. You would also have good control over pressure and coverage and could avoid having to use any metal object that might mar the expensive castings.

 

Ciao

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8 hours ago, The Chief Smeg said:

This might sound like a daft idea Roma, but have you considered getting a ‘comb type’ thing printed that would allow you to scrape the grooves clean?

 

Thanks Chief Smeg,

 

but sorry, this tool is way too complicated. i5684_no2.gif

 

Unfortunately, you have to get into each groove to remove the wax residue, and therefor in addition to brushes a steel ruler or a dental probe are the most effective tools. up040577.gif&key=327a20a361d18ad6d35cabf

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