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Comment by londons_explore | Hacker News Reader

I would expect "glue in a hole" to fail as the sun hits the module every 90 mins, and the surface probably heats to 100C and cools to -25C. That kind of heat cycling causes expansion and contraction, causing the boundary between the metal and the glue to weaken then fail.

One can test for that in the lab, but it involves heat cycling for a long time to reproduce the same number of cycles the space station could undergo in its multi-decade lifespan.

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You can do that on Earth if your thermal vacuum chamber is big enough. They will run accelerated hot/cold cycles while under vacuum to simulate something like 30 transitions but if the glue in the hole held out through the entire test, there would be no way to find it. That vehicle had been up there since June so it did pretty well for an unreported patch job.

only the exterior blankets would have such extreme temperature cycles, the inner aluminum hull would have a much more stable temperature. The diurnal would be much more benign. Still enough for CTE and fatigue to cause a failure.

Where do you get this glue info? I don't see it in the article.

So someone accidentally drilled through an expensive space station module on earth and filled the hole with glue. Wow..

Third paragraph, with a quote directly after it:

An unnamed source told RIA Novosti the person responsible for drilling the hole filled it with glue instead of reporting the mistake.

"The glue dried and was squeezed out, opening the hole," the source told the media outlet.

It's fun that the astronauts did the proper/final fix with epoxy, which to most people is of course also a glue. So perhaps the worker used (or mis-used) the wrong glue to fix this, rather than tried to cover up the mistake? Of course it sounds reasonable that it should have been reported, which didn't happen, so so the working environment seems improvable.

Also I believe the astronauts used epoxy to glue a patch over the hole, instead of just filling the hole with glue/epoxy, so the current solution should be much more structurally sound.

Epoxy's probably the best you can do in space but on the ground I imagine it would have been better to weld or replace the part.

I think "the part" in this case is the entire pressure vessel. You would have to disassemble everything and build a new capsule out of the parts.

The thing that gets me is that the glue "squeezed out" of the hole? What did they use? Hot glue? Rubber cement? Once epoxy hardens it might break up but it's not going to squeeze through anything.

Ugh ok, wtf. Believe it or not but with JS disabled I get a completely different text that doesn't mention glue.

I can reproduce that on chrome with JS off. It looks like the first two paragraphs are there but covered by the image.

It's just hidden behind the photograph. Inspect element or view source and you'll see it.

Safari, JS disabled, text appears just fine for me.

Maybe it was reported and the "proper" fix at that time was to use that glue.

If it was reported there should be records.

Oh you sweet summer child. /s

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