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

[spaceman]

Hello everybody,

 

before I get to the details of the Door Actuator Pneumatic Drive which sit in and on the frame box, I first have glued the four short support struts onto the bottom frame of the second box. 

 

Doing it, picking up and securely holding these 2 mm long tiny strips is a special exercise that requires a lot of patience and two steady hands, since the tip of the tweezers just barely fits over them.  

 

 

And then you have to dip the tiny strip carefully into the blob of glue and place it correctly as soon as possible, which is why the frame has to be firmly fixed, that's the be-all and end-all of the matter. 

 

After that I've always still aligned the strips,

 

 

namely from both sides, so that they stand vertically after gluing.  

 

 

And already I had twins. 

 

 

And so to the drive details which sit in and on the frame box,  which I've puzzled my head over for quite some time to first understand their construction, 

 

 

and then to determine the dimensions of the individual parts on the screen and to scale them to my scale (1:160) using a reference measurement (blue), which is always very time-consuming, especially since you still have to determine dimensions from other image views. 

 

Source: NASA (STS-132)

 

In order to preferably keep an overview, I have numbered the individual parts, 

 

Source: NASA (STS-135)

 

an those would be:

 

1 Gear box, 2 Coupler, 3 Base plate, 4 Pneumatic cylinder, 5 Pneumatic pipes, 6 Horizontal pipes, which are connected to the Screw jacks. 

 

In the next image one can see three more parts:

 

7 Shaft, 8 Screw, 9 Coupler, which I want to leave it at for now. 

 

Source: NASA (STS-132)

 

Then I started scratching the individual parts, the small white Base plate 3 (0,13 mm x 1,7 mm x 1,7 mm) was quickly cut to size.

 

For the back upright standing Gear box 1 I used an Evergreen strip (0,5 mm x 1,5 mm x 3 mm),

 

 

to the front of it I glued a black faceplate (0,25 mm) to achieve the required thickness of 0,75 mm.

 

 

The Coupler 2 sits on the Base plate 1 and is a tiny cube (0,75mm x 0,75mm x 0,75 mm), whose dimensions I've corrected a bit again. 

 

 

This coupler is connected to the Gear box 1 by a Shaft 7 and still gets a small Screw 8 on the top. 

 

 

For the Hydraulic cylinder 4 I'll use a gray rod (Ø 1 mm), that sits on a Coupler 9, which might be connected to the gear box. 

 

 

As far as my interpretation of the individual parts of the Pneumatic door drive, however without claiming to be correct.  

 

Luckily it doesn't have to work. 

Edited December 24, 2022 by spaceman

[spaceman]

Hello friends, 

 

Game over at the Football World Cup and congratulations to the new world champion Argentina and to Lionel Messi as the best player of the tournament, who finally crowned his career - credit where credit is due! 

 

And with that, back to normality again and with renewed enthusiasm back to my crafting table with the Payload Canister. 

 

Well, the smaller the parts become, the more difficult the entire handling during assembly and especially when gluing them. 

 

For a better idea of the Door Actuator Pneumatic Drive, I tried to make a 1:1 drawing with the dimensions of the individual parts that I had determined, whereby the minimum distances between them let hardly be drawn. 

 

 

But it didn't make me much smarter than before, except that everything is very small, what I knew already before too.  

 

First I glued the bottom plate (3) to the coupler (2) onto both upper frames.

 

 

On closer inspection, I noticed that the part between the coupler (2) and the gearbox (1) is not a shaft (7), but belongs to the coupler, in which a shaft probably runs that connected to the gearbox.

 

Source: NASA (STS-132)
Source: NASA (STS-132)

 

For this connector I used the Punch & Die Set in order to punch two mini cylinders (Ø 0,6 mm) made of Styrene (0,5 mm).

 

 

In order to be able to glue these tiny ones onto the coupler, I had to carefully clamp the frame upright between two steel rulers, which also worked.  The only question was how I could hold this tiny plug during gluing it to the coupler? 

 

Even with the sharpest tweezers that would not work, since the coupler there only measures 0,75 mm x 0,75 mm. That's why the only option left was the method I've already practiced, carefully prickling the mini cylinder with the tip of the cutter so that it gets stuck, and setting it down even more carefully on the coupler that was previously dabbed with glue, which at least worked for the first frame. 

 

 

As one can see in this image, there is another narrow cross brace directly behind the Gearbox (1), which is helpful for later gluing the upright gearbox and provides it with support. 

 

Source: NASA (STS-132)

 

For this purpose, the frame was re-clamped again,

 

 

after which this cross brace (0,25 mm x 0,5 mm) could be glued into the frame.

 

 

To glue the gearbox, the frame must be re-clamped again, for which the two clamping rulers must be put under with a Balsa board (2 mm) so that the connector meets the gearbox ahead, what I've only tried so far.  

 

 

And this point is approx. 0,5 mm below the upper edge of the gearbox, what I determined from this image, among other things, which shows how I have to collect the dimensions for the scratch construction from different photos. 

 

Source: NASA (STS-135)

 

During the same procedure on the other frame, the night before last, late at night (1:30 a.m.), the accursed mishap happened to me again that during pinching it between the rulers the frame suddenly jumped out of the tweezers  and fell to the ground, what made my hair stand on end left because I suspected bad things. 

 

Since I unfortunately couldn't see no such thing when I first looked hopefully at the floor in front of me,  I then again on my knees searched everything around the desk with the flashlight, but finally gave up in frustration,  since I was fed up and finally wanted to go to bed ... 

 

The next morning it was time for furniture move about, for which I've pulled out the container and put the sideboard aside to be able to search properly again. 

 

 

 

Lo and behold, after I had picked up a few dust bunnies, my heart jumped for joy,  because then my inflamed eyes discovered the midget for my joy.

 

 

Then I also could glued the narrow cross brace into this frame. 

 

 

Now I can try calmly install the gearboxes into the two frames. 

Edited December 24, 2022 by spaceman

[K2Pete]

This is just a Remarkable build Manfred! Remarkable!  ;^ o

 

And the Physics of Tweezers and small parts interested me ... even though we have a very firm grip on those tiny styrene pieces, they manage to escape and fly ... seemingly with Saturn V thrust, never to be found again. It was good to see you located your "escapee", Manfred!

 

One more question, when taking those ultra close-up photos, what type of Microscope do you use!  ;- D 

 

Let me wish you a Merry Christmas Manfred! ... and my best wishers for 2023!

Pete

[crowe-t]

Manfred,  This is an amazing build.  

 

I've been on my knees more times than I can remember looking for small parts that got away from me.  I feel your pain.

 

Have a Merry Christmas and Happy New Year! 

Edited December 21, 2022 by crowe-t

[as205]

The last time I dropped a tiny part like that (about a couple of months ago) I had to resort to a vacuum with some nylon hosiery over the end to catch the part.  I was amazed that the plastic eating carpet allowed it to return.

 

I haven't noticed in your other posts, what do you use to apply the tiny amounts of glue to the tiny parts?

 

This is really an unbelievable build!

 

[spaceman]

11 hours ago, K2Pete said:

This is just a Remarkable build Manfred! Remarkable!  ;^ o

 

And the Physics of Tweezers and small parts interested me ... even though we have a very firm grip on those tiny styrene pieces, they manage to escape and fly ... seemingly with Saturn V thrust, never to be found again. It was good to see you located your "escapee", Manfred!

 

One more question, when taking those ultra close-up photos, what type of Microscope do you use!  ;- D 

 

Let me wish you a Merry Christmas Manfred! ... and my best wishers for 2023!

Pete

 

Thanks Pete for your nice comment.  

 

A firm grip is relative and depends on the size of the midgets and the quality of your tweezers, e.g. like this one, just still sufficient for holding an Evergreen Strip (0,25 mm x 0,5 mm),

 

 

And for taking those ultra close-up photos I don't need a Microscope but only my good old Digicam Panasonic DMC-FX 30 with MEGA O.I.S./28 mm WIDE and self-timer. 

 

Thank you very much, Pete, for your best wishes for Christmas and a hopefully better and and peaceful 2023 for all of us! 

 

 

 

[spaceman]

9 hours ago, crowe-t said:

Manfred,  This is an amazing build.  

 

I've been on my knees more times than I can remember looking for small parts that got away from me.  I feel your pain.

 

Have a Merry Christmas and Happy New Year! 

 

Thanks Mike for your nice words  and your sympathy regarding these crazy wayward little monsters ... 

 

I wish you and Patricia also a Merry Christmas and Happy New Year! 

[spaceman]

3 hours ago, as205 said:

The last time I dropped a tiny part like that (about a couple of months ago) I had to resort to a vacuum with some nylon hosiery over the end to catch the part.  I was amazed that the plastic eating carpet allowed it to return.

 

I haven't noticed in your other posts, what do you use to apply the tiny amounts of glue to the tiny parts?

 

This is really an unbelievable build!

 

 

Thanks my friend for sharing your experience in hunting these damned midgets, one never stops learning. 

 

BTW, in the next post I'll go into my trick of applying tiny amounts of glue to those tiny parts. All you need is only a small tool from medical technology, therefore stay tuned. 

[spaceman]

Hello everybody,

 

and with this I'll come now  to the gluing of the Gear box (1) in the narrow space behind the Coupler (2) and the cross brace, which I've been puzzling my head over for a long time broken how best to do it,  among other things about how I can hold and act on the fragile frame in the most gentle way, because there is not much space for safe access. 

 

To do this, I first grabbed the frame with the tweezers directly behind the cross brace, have fixed the tweezers in this position with a clamp,

 

 

and parked in such a way that the gearbox can be pushed into the gap with another pair of tweezers.

 

For a quick sequence of steps when gluing, I grabbed the Gear box with the pointed tweezers and also fixed them with a clamp for quick access and put them aside. So much for the theory.

 

 

And now to my trick of applying tiny amounts of glue to those tiny parts, wherefore I use such a Acupuncture needle (Ø 0,2 mm),

 

 

 

that fits comfortably in the narrow gap, as one can see here, still without glue. 

 

 

 

Then I've dripped a small drop of Revell glue onto the aluminum foil plate, dripped a small drop of Revell glue onto the aluminum foil plate and dipped the acupuncture needle's top into it. 

 

 

 

Then I've carefully dabbed this tiny drop of glue into the narrow gap with my eagle eyes onto the cross brace, and immediately carefully inserted the Gear box into the gap from below with a lot of feeling and a steady hand in front of the cross brace and glued to it. There isn't much time for alignment and correction, but it's still possible.  

 

 

Then the coupling flange was still glued to the upper end of the Gear box with MEK.

 

 

And that was it already, and I was finally able to let go of the frame and lay it down. http://www.raumfahrer.net/forum/yabbfiles/Attachments/up035091.gif

 

 

 

 

I could be quite satisfied with this result, which is roughly what I had imagined.  

 

 

And with the frame laid on the bottom part, the first Door Actuator Drive is taking on more and more shape and I like it. 

 

 

 

And in the same way I glued the other Gear box into the second frame, which wasn't rocket science anymore once you know how to do it. 

 

 

 

 

Now I can tackle the two Pneumatic cylinders (4) on the underside of the frames. 

Edited December 24, 2022 by spaceman

[spaceman]

Hello friends,

I wish you all a Merry Christmas and Happy Holidays. 

[crowe-t]

Merry Christmas and Happy New Year!

[Slartibartfast]

Merry Christmas, y’all.

[spaceman]

Hello everybody,

 

I hope you tolerated all the culinary delights well and were happy about the presents.  

 

Now that the holidays are over, I want to get back to the crafting table and carry on a little further to finally finish these tricky Door drives. 

 

In the meantime, I've also gotten a little more clarity about the possible function of this special drive and transmission technology, what is always part of it for me.  

 

Doing it I found out that my Coupler (2) is a Bevel Gearbox, through which the shafts in the horizontal pipes (6) are driven, which are connected to the Screw Jacks, which are connected with the upper linkages of the Door Actuators on the canister doors, by means of which the doors can be opened and closed. 

 

Source: NASA (STS-135)

 

Such a Bevel Gearbox has the following basic structure, whereby the implementation of a rotary movement of a drive shaft within an angle of 90° to an output shaft is effected by means of bevel gears. 

 

Source: drivelines.co.uk

 

And this Output shaft is located in the horizontal pipes (6) on either side of the door operator and is connected at both ends with Screw Jacks. The lifting movement of the rotating spindle with trapezoidal thread is carried out via a worm gear, which is located in a gear housing, as can be seen in the image on the right. 

 

In the lower area, the vertical lifting spindles are surrounded by a protective tube and in the upper area they are covered by black Folding bellows to protect against dirt, which are folded when doors are opened and unfolded when doors are closed.

 

Source: mechjacks.com

 

Next I want to scratch the gray Pneumatic Unit with the dome-shaped Cover (4) in front of the Housing (9), whatever these parts may be called, which unfortunately I haven't been able to find out yet. 

 

Source: NASA (STS-135)

 

Anyway, both parts in 1:160 are pretty small, but more on that in the next post. 

[spaceman]

Hello everybody in the old year,

 

and so let's go right ahead with the midgets of the Pneumatic Unit.  

 

For the Housings (9) I've sanded two Styrene blocks (0,7 mm x 1,3 mm x 1,6 mm), and for the dome-shaped Cover (4) I did use a rod (Ø 1 mm x 1 mm) painted gray.

 

 

The small plugs were glued on in the usual way by using the proven fixation between the steel rulers. 

 

 

 

The tiny Screw (8) on the Bevel Gearbox (2) I've hinted with a Fineliner (0,05 mm).

 

 

Now the Housings (9) of the Pneumatic Unit still had to be painted grey,

 

 

for which I've thought of a clever solution using a Paulaner Crown cap as a turntable with a tape strip glued on in reverse, 

 

 

which also worked fine. 

 

 

Now all I have to do is glue these things to the underside of the frame onto the rear Gear part (1), which should become pretty tricky,  which is why I'm going to try that next year. 

So it's time to say goodbye for this year and I wish everyone a happy New year. Come across well and stay tuned! 

[crowe-t]

Happy New Year! 🎉

Edited January 1, 2023 by crowe-t

[spaceman]

 

[spaceman]

Hello everybody in 2023,

 

I hope you all slipped in well and are in good spirits. 

I also want to get off to a flying start and show how I assembled the Door drive, which consists of limply 20 individual parts if I counted correctly.  

 

Before assembling both frames, however, the Pneumatic unit had to be glued to the rear Gear part (1) of the upper frame, for which I had to come up with a special holding device again,  so that the fragile assemblies do not break down.  And for this, only a magnetic holder was possible, for which the free end of the frame behind the gear part with 1 mm was just enough,  

 

 

wherefore I also needed a spacer template. 

 

 

But then came the much more difficult exercise, namely gluing the upper frame onto the feet of this small table. 

 

 

As can be seen from the following images, everything only worked again using special clamping technique, 

 

 

by having the magic touch for this tricky job, 

 

 

and softly, softly, catchee monkey ... 

 

 

But it finally worked,  although it was quite stressful because some struts had to be aligned and partially re-glued.  

 

 

And in the mounting position, the Door Actuator Pneumatic Drive looks quite passable. 

 

 

But now the lateral struts, which had been prepared for some time, still had to be glued at the back of the frame, 

 

 

here with the strut during a first fitting on the canister, which fitted quite well. 

 

 

Then the second strut was glued opposite, 

 

 

 

with which the first door drive was finally complete. 

 

 

And this is the final test fitting of the drive on the Starboard Side of the canister,

 

 

which has withstood my critical eye. 

 

Edited January 2, 2023 by spaceman

[spaceman]

Hello everybody,

 

and now the Door actuator followed for the other canister side using the same knitting pattern. 

 

 

 

With this the Port Side now also has its door drive.

 

 

Next up are the bottom linkages of the Door actuators on which the Screw Jacks are mounted.

 

Source: NASA (STS-135)

 

They are similar to the adjacent Access Platforms in terms of the structure of the mount, but are much narrower and therefore a bit more complicated, as one can see on this section at higher magnification, 

 

Source: NASA (STS-135)

 

which is also good usable for determination of the dimensions needed for scratch building, what is now my next task. 

[spaceman]

Hello everybody,

 

and I tackled that right away, which resulted in the following dimensions. 

 

Source: NASA (STS-135)

 

In order to keep track of it myself, I marked the determined heights and widths in color, especially since they also were determined by using different reference dimensions (blue). 

 

As reference dimensions I've used the dimensions of the Wall braces of the door actuators, which are identical to those of the Screw jacks.  

 

But that's still not all the dimensions I need. A few widths from a front view of the screw jack are still missing, which cannot be determined exactly from this slightly slanted side view.

 

And for that this photo is a good reference. 

 

Source: NASA (STS-135)

 

Determining the dimensions is always extremely time-consuming and a tiring torture for the eyes,  but unfortunately I have to bite the bullet again and again , because unfortunately nothing can be scratched without dimensions. 

 

The Wall braces I've put aside some time ago already. 

 

 

Now I have to go through my stock and see which profiles I can use for the remaining parts. 

Edited January 10, 2023 by spaceman

[CaptKirk]

I'm hoping that you don't read the dimensions from a conventional steel ruler, Manfred. A digital vernier with a large screen can be had for much less than you must spend on styrene each week... 😄

[spaceman]

Thanks Kirk for your joky comment, 

 

you'll laugh, but that's exactly what I'm doing every day, which is why I'll show you my plastic ruler and my digital caliper.  

 

 

 

But that shows me that you're not such a loopy scratch builder like me. 

 

Since I measure the distances on the monitor, the plastic ruler is the much simpler, better and, above all, faster tool, with which I can measure with an accuracy of up to 0,5 mm without any problems, which is completely sufficient for the selected photo enlargement. 

 

OMG, that's why I wouldn't dream of doing it with the vernier caliper, especially regarding the time required for a measurement, that would really drive me crazy definitely ...  Just converting all the dimensions to 1:160 takes a lot of time ... 

 

BTW, measuring with the caliper on the display would be deadly for the monitor,  and sometimes even a 30 cm long ruler is not enough yet ... 

 

So, I hope you got a little insight into my Real Space Modeling Measurements ... 

 

 

Edited January 8, 2023 by spaceman

[spaceman]

Hello everybody,

 

speaking about measurements with a steel ruler vs a digital caliper. 

 

Only a short question, especially for my friend Kirk. 

 

 

What do you think, how long will the snippets be that I can cut with this ruler setting using my cutting method with the steel rulers? 

 

 

Edited January 10, 2023 by spaceman

[CaptKirk]

Is it 1.25mm, or am I missing something?

(Thanks for your explanation of how you scale, by the way. It had genuinely never occurred to me to scale directly from the screen. It makes great sense.)

[spaceman]

Hi Kirk,

 

definitely, these are my standard methods meanwhile. 

 

My compliments, you have a good sense of proportion too, which is nearly the same measure what I also would read off. 

 

And so to the background of my estimation question. 

 

For the frame struts of the Screw Jacks I will use Evergreen Strips (0,25 mm x 0,5 mm).  

 

Since the frame is only 2 mm wide, the gap is 1,5 mm, which is why I need a total of 8 snippets of this length.

 

Therefore I initially set the steel rulers exactly to 1,5 mm, but I was surprised that the resulting snippet was 1,7 mm long when measured with the vernier caliper. 

This fact is actually well known to me, but I fall for it again and again. 

 

That's why I gradually approached the final dimension of 1,5 mm, which led to this setting. 

 

 

Here is the result with this setting by using the vernier caliper, 

 

 

 

with which I can now cut off these snippets for the four Screw Jacks.  

 

And in addition to the 1,5 mm short snippets, I have meanwhile also cut off the upper Frame struts 2 (4 mm).

 

 

For the Vertical struts 1 (4 mm) I need the same length, which finally results in the total height of the frame being 4,5 mm. 

 

Source: NASA (STS-125)

 

As one can see easily the squirrel feeds itself arduously ... 

Edited January 11, 2023 by spaceman

[CaptKirk]

Hi Manfred. I'm guessing that the additional length comes from the chamfer on the blade?

I have a vague recollection that one of the master builders I have followed - either you or Rich O - had bought a guillotine for just this sort of task. So I suppose it must have been Rich. I'm still amazed at how leniently the carpet monster is treating you with these tiny parts; my local one gobbles any styrene ( no matter how large) that makes it to within a metre of my cutting mat...