Space Shuttle Launch Pad 39A with Challenger STS-6 (1:144) - Page 188

**spacerunner** · #**1871** 12-03-2018, 06:51 PM

Hello everyone,

after my longer stopover at the London bus stop of the Route 76 Waterloo-Victoria, as well as after the exhausting but ultimately successful 3D prints of the Track Shoes and Main Sprockets for the Crawler Trucks I want to turn once again to the Early LWT (ET-8).

After a long bickering in summer with Shapeways' service team, with whose print quality of the modified WSF Intertanks (right) I neither was satisfied, nor I wanted to accept that fact,

I had been fiddling even further together with Michael Key and at the same time still modified some so far missing details. These concerned the so-called Flange Closeouts at the connections of the Intertank with the LH[sub]2[/sub]/LO[sub]2[/sub] tanks, which were sprayed by hand.

Source: NASA

This photo shows such a Flange Closeout area after manual machining completed.

Source: facebook.com (Craig Capdepon)

These Closeout areas I've looked at in my photos of the ET-8 again closer and had marked them in the following images for a detailed discussion based on Michael Key's current 3D model.

Source: forum.nasaspaceflight.com (Jester)

Source: retropaceimages.com (STS-6)

By comparison, this transitional area had not yet been differentiated enough in his model, what I have explained to him.

While the flat area of the Closeout-2 is too narrow, the subsequent beveled area appears a bit too wide, which I have marked in this photo, and what one can see clearly on the right edge.

Source: georgesrockets.com (George Gassaway)

In the next image I've put the original photo and the 3D model directly next to each other for comparison. As one can see, the flat area of the front Closeout-2 should be widened to 2,5 mm, so that the remaining slope is only 1 mm wide, measured to the leading edge of the IT, i.e. 12 mm is the distance from the lower edge of the vent to the leading edge of the IT.

BTW, the Closeouts at the end of the IT require the same changes I've marked with tape to overview at this WSF-IT.

These changes were largely taken into account in the next model except for a small detail.

In his model, however, there is no smooth transition from Closeout-2 to the 'normal' Closeout, but a step/staircase that is caused by the different inclinations of both areas, which is not correct.

However, by widening the flat area of Closeout-2 should allow a smooth transition with the same slope.

**spacerunner** · #**1872** 12-03-2018, 06:52 PM

And even these transitions could finally still be adjusted, after which the 3D model looked perfect.

And this is now definitely the final Early LWT Intertank for my STS-6 Shuttle Stack,

Source: shapeways.com (The Aerospace Place)

but which I did not order it in WSF, but in FUD, that was delivered in the meantime too. Unfortunately, one can not see well the Closeout details on these FUD photos because of the transparency of the material.

And the IT also fits well with the other two Airfix ET parts,

but has now to be thoroughly cleaned again in the ChiliDent Laboratory, wherewith finally would be completed this stressful IT chapter.

And on this occasion, the Track Shoes and Main Sprockets will be patched up as well.

**spacerunner** · #**1873** 12-21-2018, 12:39 AM

Hello my true friends,
the guys from ChiliDent gave the green light, starting from 7th January I can get in touch.

BTW, I've finally finished the London bus for the wife of my late boyfriend Thomas (†54), and meanwhile he arrived safely, survived unscathed and will surely be a nice Christmas present.

In this sense Merry Christmas and a Happy New Year to you all.