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-   -   Apollo SM RCS units. (http://www.oldrocketforum.com/showthread.php?t=17761)

luke strawwalker 02-15-2019 08:03 PM

Quote:
Originally Posted by Earl
Take a look at the photo link in my prior message and a second look at your photos (I have similar photos of those same RCS quads at KSC myself).

The quad *boxes* themselves are silver...that 'top of the box' white you see is the 'printing' I mentioned above. I think it might actually be a label applied to the top of the quad box.


Earl


Yep hard to go by museum stuff, particularly the ones that have been on outside display... the get corroded or paint or coatings become discolored or peel and get painted over with "whatever is available" or "whatever they can afford" and that's that... particularly years ago when keeping it "as close to original as possible" wasn't any particular priority...

The writing appears to be a chart that helps with wiring and orientation for translation... the motors had to be wired correctly to fire in the appropriate pairs or orientation to provide the required rotation of the vehicle in the +/- X, +/- Y, and +/- Z axes, as well as thrusting forward and aft, and translating the spacecraft up/down and side to side in those planes...

Later! OL J R :)

Earl 02-15-2019 08:18 PM

Quote:
Originally Posted by luke strawwalker
Yep hard to go by museum stuff, particularly the ones that have been on outside display... the get corroded or paint or coatings become discolored or peel and get painted over with "whatever is available" or "whatever they can afford" and that's that... particularly years ago when keeping it "as close to original as possible" wasn't any particular priority...

The writing appears to be a chart that helps with wiring and orientation for translation... the motors had to be wired correctly to fire in the appropriate pairs or orientation to provide the required rotation of the vehicle in the +/- X, +/- Y, and +/- Z axes, as well as thrusting forward and aft, and translating the spacecraft up/down and side to side in those planes...

Later! OL J R :)


I think the JSC Saturn V was completely restored/repainted when it was enclosed, and maybe the same for the KSC and ASRC Saturns as well.

I am surprised, somewhat, to see the JSC Service Module (and quads) with the paint scheme it shows. The main 'body' of the Service Module has been rendered in a plain gray, which I'm pretty sure NO flight Saturn V ever had. The radiator panels as white is correct, but the solid white quad boxes is not.

John Pursley, who posts here some, was heavily involved with the JSC project as I recall and is one of the foremost Saturn V modelers/historian. Maybe he can fill us in at some point on some of those color choices, but they seem out of place to me when compared to many, many flight vehicle images.

The KCS Service Module and Command Module you featured in your first batch of photos is, as I recall, actual leftover flight hardwear and appears to have never been mollested from a 'restoration' effort. I have looked over that hardware there on a number of visits to KSC over the years and have some extensive photos of it, but they are not easily at hand (a la paper prints).

Earl

rocketguy101 02-15-2019 09:22 PM

1 Attachment(s)
I have a closer shot of the Cosmosphere CSM...I took it precisely because this question came up during my Saturn 1B scratch build

MarkB. 02-15-2019 10:00 PM

Comrades:

I use flat aluminum and Testors Jet Exhaust for the thrusters. They look great and just like the picture above.

blackshire 02-21-2019 06:08 AM

Quote:
Originally Posted by Earl
I think the JSC Saturn V was completely restored/repainted when it was enclosed, and maybe the same for the KSC and ASRC Saturns as well.

I am surprised, somewhat, to see the JSC Service Module (and quads) with the paint scheme it shows. The main 'body' of the Service Module has been rendered in a plain gray, which I'm pretty sure NO flight Saturn V ever had. The radiator panels as white is correct, but the solid white quad boxes is not.

John Pursley, who posts here some, was heavily involved with the JSC project as I recall and is one of the foremost Saturn V modelers/historian. Maybe he can fill us in at some point on some of those color choices, but they seem out of place to me when compared to many, many flight vehicle images.

The KCS Service Module and Command Module you featured in your first batch of photos is, as I recall, actual leftover flight hardwear and appears to have never been mollested from a 'restoration' effort. I have looked over that hardware there on a number of visits to KSC over the years and have some extensive photos of it, but they are not easily at hand (a la paper prints).

Earl
Apollo 6's Service Module was mostly white (it was the only one of that color), while the others had various combinations of metallic finishes (not painted, at least for the most part). The Skylab Command Modules were mostly white (I think), due to their longer in-space stays and sunlight/darkness exposure cycles; this doesn't seem to have necessitated any surface finish changes for the Skylab Service Modules (even Vanguard 1, which has an all-metallic finish, didn't have any day/night thermal cycle problems, as it transmitted for six years, until radiation finally degraded its early-type solar cells).

Earl 02-21-2019 06:44 AM

Quote:
Originally Posted by blackshire
Apollo 6's Service Module was mostly white (it was the only one of that color), while the others had various combinations of metallic finishes (not painted, at least for the most part). The Skylab Command Modules were mostly white (I think), due to their longer in-space stays and sunlight/darkness exposure cycles; this doesn't seem to have necessitated any surface finish changes for the Skylab Service Modules (even Vanguard 1, which has an all-metallic finish, didn't have any day/night thermal cycle problems, as it transmitted for six years, until radiation finally degraded its early-type solar cells).


Yes, of the Apollo missions, specifically the Saturn V missions, Apollo 6 was kind of the odd man out with that pretty much fully white SM. Here again though, it was not the gray color as shown on the JSC Saturn V currently on display, so I'm still not sure where the JSC folks came up with that color combination.

As best I can tell from the harware I have seen on display (some of which was actual excess flight hardware), the 'silver' color of the SM appears, in many places, to be a silver paint (high temp one would assume) over the outer structure. I had assumed for many years until I actually saw some of this hardware that the 'silver' we all saw in the launch photos and such was actual 'bare metal'. Not the case in most instances. It seems that, as I recall, a good portion of the SM outer surface is covered in a layer of somewhat thin insulation (possibly a cork-type material, as was the case for a portion of the Boost Protective Cover or BCP for the Command Module) which was then painted with this silver paint. From any real distance however it appears to be a metallic surface.

The 'silver' of most Command Modules (save for the Skylab CM's as you noted above) is a covering of relatively narrow strips of what I recall to be highly reflecitve mylar, definately giving it the appears of a bare 'metal' finish (as a kid, I thought this outer surface was some type of relatively light stainless steel shell of some sort). These strips of material can be seen burnt off and hanging in small, torn sections on many CM's during recovery operations in the ocean.

Earl

BEC 02-21-2019 01:40 PM

Quote:
Originally Posted by Earl
It seems that, as I recall, a good portion of the SM outer surface is covered in a layer of somewhat thin insulation (possibly a cork-type material, as was the case for a portion of the Boost Protective Cover or BCP for the Command Module) which was then painted with this silver paint.


This is what John Pursely told us as he was leading us in a tour of the JSC Saturn V at NARCON last year.

jeffyjeep 02-21-2019 06:26 PM

My thanks to all of you for your help with this! I’ll paint the RCS units when I return home from a job in Kittery, Maine in March. Yes, it’s cold here!

blackshire 02-21-2019 09:17 PM

Quote:
Originally Posted by Earl
Yes, of the Apollo missions, specifically the Saturn V missions, Apollo 6 was kind of the odd man out with that pretty much fully white SM. Here again though, it was not the gray color as shown on the JSC Saturn V currently on display, so I'm still not sure where the JSC folks came up with that color combination.

As best I can tell from the harware I have seen on display (some of which was actual excess flight hardware), the 'silver' color of the SM appears, in many places, to be a silver paint (high temp one would assume) over the outer structure. I had assumed for many years until I actually saw some of this hardware that the 'silver' we all saw in the launch photos and such was actual 'bare metal'. Not the case in most instances. It seems that, as I recall, a good portion of the SM outer surface is covered in a layer of somewhat thin insulation (possibly a cork-type material, as was the case for a portion of the Boost Protective Cover or BCP for the Command Module) which was then painted with this silver paint. From any real distance however it appears to be a metallic surface.

The 'silver' of most Command Modules (save for the Skylab CM's as you noted above) is a covering of relatively narrow strips of what I recall to be highly reflecitve mylar, definately giving it the appears of a bare 'metal' finish (as a kid, I thought this outer surface was some type of relatively light stainless steel shell of some sort). These strips of material can be seen burnt off and hanging in small, torn sections on many CM's during recovery operations in the ocean.

Earl
Ah--that makes sense. The cork-like insulation likely had a somewhat shiny outer coating (possibly for rain protection on the pad), which made it look like an unpainted but somehow "treated" (anodized, sand- or bead-blasted, etc.) bare metal surface (and here is a Skylab CSM docked to Skylab: https://space.stackexchange.com/que...csm-white-paint ). Also:

I once read that Maxime Faget didn't think the metallized Mylar was necessary on the Command Module for re-entry protection because it was on the lee side, behind the heat shield (it helped for thermal control in space, but the Skylab CMs' white finish worked just as well for that), and that NASA was being "old hen-ish" and overly conservative by requiring it to be applied to the spacecraft. After Apollo 4 landed after a lunar return velocity re-entry (although it might have been Apollo 8 or a later lunar-return Apollo, as I'm not sure if Apollo 4's CM had the metallized Mylar sheathing), he triumphantly showed a removed, un-burned swatch of the metallized Mylar to the NASA personnel who had insisted that it was necessary for re-entry protection.

tbzep 02-22-2019 07:03 AM

It might not have been necessary, but it sure made the Apollo 9 EVAs look cool wth Scott's and Schweickart's red helmets in the frames.




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