Hi, in this NASA workshop handout on hermeticity testing there are a number of photos of semiconductors and some SMPS-looking hybrids. I'm wondering what the material is that they've used to tack down fly wires and such like. Is it a special epoxy or some kind of flexible silicone or something else entirely?
(pages 19, 22, 25, 28, 30)
Thanks for any info
--sp
On a sunny day (Thu, 19 Mar 2015 11:55:22 -0400) it happened Spehro Pefhany wrote in :
Looks like some rubber.
I 'sealed' a 'super sealed lead acid battery' yesterday with araldite. it was blowing bubbles next to the - (lead) connector). Araldite:
Den torsdag den 19. marts 2015 kl. 16.52.40 UTC+1 skrev Spehro Pefhany:
looks a bit like the stuff used to glue components
-Lasse
Sure looks like red glyptal to me.
Cheers
Phil Hobbs
-- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net
Maybe epoxy. Epoxy would be less outgassey.
-- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
Yup, I agree, it is glyptal. Haven't seen this stuff in years, but I guess NASA is smart to stay with time-tested stuff that is known to work!
Jon
It does but there is one picture where it was attached to a cover, so I,m guessing some type of silicone, maybe Sylgard.
Cheers
I agree, red glyptal, an alkyd enamel insulating compound. Only for light duty tacking e.g. trimpot adjustment setting. For staking heavier components I think NASA specify two part expoxies.
piglet
Interesting.
There's no specific listing for glyptal in the outgassing report (or anything that, at a quick glance, looks similar in the relevant section). Oh, well, was just curious. I don't think I've seen this stuff in a hybrid before. The stuff used to hold parts down is usually more red in color.
--sp
Well, that was some pretty old technology. But, it could have been updated. That is essentially what they are doing now, the Orion is basically an Apollo capsule brought up to date.
Jon
One of the many examples of Robert S. McNamara's arrogance was his insisting that all copies of the plans for the Saturn V be destroyed, so they could never make another one.
Cheers
Phil Hobbs
-- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net
Actually that seems to be Bad Info. McNamara was still an arrogant ass, but he wasn't guilty of that particular example.
Cheers
Phil Hobbs
-- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net
We can't buy a set from the Russians?
The Saturn 5 plans are in storage at the Marshall Space Flight Center.
References:
Saturn 5 Blueprints Safely in Storage By Michael Paine Special to SPACE.com posted: 06:34 am ET
13 March 2000A NASA official has denied a claim made by a book author that blueprints for the mighty Saturn 5 rocket used to push Apollo astronauts to the moon were lost.
The denial came in response to a recent story in SPACE.com that reported on a claim John Lewis made in his 1996 book, Mining the Sky, that he went looking for the Saturn 5 blueprints a few years ago and concluded, incredibly, they had been "lost."
Paul Shawcross, from NASA's Office of Inspector General, came to the agency's defense in comments published on CCNet - a scholarly electronic newsletter covering the threat of asteroids and comets.
Shawcross said the Saturn 5 blueprints are held at the Marshall Space Flight Center on microfilm.
"There is no point in even contemplating trying to rebuild the Saturn 5 ... The real problem is the hundreds of thousands of parts that are simply not manufactured any more."
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Blueprints and other Saturn V plans are available on microfilm at the Marshall Space Flight Center.
The Saturn plans are still at Huntsville. However, the contractor infrastructure is gone, many subassemblies were farmed out to small shops that are either out of business or who have long since discarded the necessary tooling. It's estimated it would cost at least $16 billion to retool to produce Saturns to the old plans.
It should also be noted that Saturn didn't have very many flights, so reliability statistics are not available. This is a similar problem to that facing Energia. Many NASA and contractor engineers believe we were incredibly lucky with the Apollo program and that if it had continued we would have inevitably lost missions. Also Saturn launches were expensive. They cost about $550 million in *1967* dollars. A 1993 dollar is worth 12.5 cents in 1967 dollars so multiply costs by 8 to get current pricing.
In reality you wouldn't want to reproduce Saturn in any event. There have been sufficient advances in most of the flight systems since Saturn was designed that a clean sheet of paper approach would be better. It wouldn't be possible to get the avionics components used, they are no longer made. So new flight systems would be required.
The F1 engine could be resurrected fairly cheaply, but better engine designs exist. And tankage is pretty much tankage, though the ongoing problem of Saturn was never really solved. Saturn was designed in the days of slide rules and drafting boards. With today's advanced design tools, CAD and CADCAM, finite structural analysis, etc, a lighter, stronger version could be designed with considerable confidence that it would work to near spec.
The advantage of glyptal for use on trimpots is that it's nice and brittle, so if the paint isn't cracked, the setting hasn't moved.
Cheers
Phil Hobbs
-- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net
The other advantage is that it's brittle, so if you want to change the pot you can easily break the "seal" and glop it again after you're done.
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