1/6 Scratch Built SURVEYOR 3

Gallery Article by Graham Symmonds on Dec 16 2009

 

1/6 scale Scratch Built SURVEYOR 3 - November 20 1969

OK.  I have never attempted anything in this scale – literally or figuratively.  Finally, after 7 months of plodding along, I finished.  I had thought I could be done by the 40th anniversary of the event – but I missed it by a few days! 

From NASA’s files:

Surveyor 3 was the second spacecraft of the Surveyor series to achieve a lunar soft landing. The specific objectives for this mission were to: (1) perform a soft landing on the Moon within the Apollo zone and east of the Surveyor 1 landing site; (2) obtain post-landing television pictures of the lunar surface; (3) obtain information on lunar-surface bearing strength, radar reflectivity, and thermal properties; and (4) use the surface sampler to manipulate the lunar surface and observe the effects with the television camera.

Surveyor 3 was launched at 07:05:01 UT (2:05:01 a.m. EST) on 17 April 1967.   Initial touchdown occurred at 00:04:17 UT and final touchdown at 00:04:53 UT on April 20, 1967 (19:04:53 April 19, EST) at 3.01 S, 336.66 E (selenocentric). The spacecraft slid about 30 cm following final touchdown. Surveyor 3 came to rest on a 14 degree slope inside a subdued 200 meter crater in southeast Oceanus Procellarum roughly 370 km south of Copernicus crater.

The last data were returned on 4 May 1967 at 00:04 UT and Surveyor 3 failed to come back to life following the two week lunar night.

On 19 November 1969 the Apollo 12 Lunar Module (LM) landed within about 180 m of the Surveyor 3 spacecraft. Astronauts Pete Conrad and Alan Bean visited the spacecraft on their second moonwalk on 20 November, examining Surveyor 3 and its surroundings, taking photographs, and removing about 10 kg of parts from the spacecraft, including the TV camera, for later examination back on Earth.

I like to think of this as the world’s first extra-terrestrial archaeological expedition.

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This turned from a labour of love into a seemingly never-ending ordeal and back to love.  I’d always liked the Surveyor spacecraft and was hoping that at some point someone, somewhere would make a kit of it.  Seeing none, I began to think “Hey, it’s only a truss tube frame with some boxes and balls ‘n stuff.  How hard can it be?”  With that I ventured down to the local hobby shop and acquired what I thought would be a sufficient amount of Evergreen Tubing (as it turned out I was dreadfully wrong and spent the next several months either ordering new pieces from Plastruct, wandering the aisles of the LHS looking for pieces, or just trying to make do!)  Plastruct was the real saviour of the project – they have just about all shapes available – and I needed just about all of them (especially reducers)!

Let me say that I now have a true appreciation for the mold-masters, tool makers and engineers who work at Tamiya, Trumpeter etc.  After spending 7 months: scaling pictures, calculating angles, figuring out supports, determining construction sequences, identifying materials, etc etc I have a new found respect for what they can achieve – realistic, scale accurate models that are easy to build!  The next time I am constructing a kit and I ask myself, “Why on earth would they not include this detail piece?” I will hearken back to the joys of the past months and remember…..

Anyway – back to the process.  There are no good scale drawings of this spacecraft.  Nor are there any really good overall photos.  The one remaining terrestrial unit is at the NASM in Washington – hung from the ceiling in such a way as to prevent good photos of one side and from the top.  The NASA Apollo image files are good, if limited in their scope.

In the end, I found a couple of mission design reports from NASA archives that had three drawings in them.  One piece of cryptic information – “z-axis to center of footpad” was provided: 77 inches.  That became the basis for a scaling exercise of finding diameters, lengths, angles etc.

Once I had some of the basic measurements, I began construction with the legs and the space frame major trusses.  My first attempt was a disaster – the lander leg looked like two pencils stuck in Captain Blackadder’s nose.  It was then I realized that I needed to recalibrate the exercise.  I’d need some more bits.

Many hours were spent looking at photos of the spacecraft and trying to piece together which truss went where and trying to devise connection methodologies.  I was particularly concerned with making sure that the major stress points were strong enough.  For the lower spaceframe, that meant sleeving the angles to which the lower leg tubes would connect with aluminum tubing.  For the planar array/solar panel mast head, it meant inserting a metal rod buttressed against the inner wall of the mast to provide a moment resistance.  To be honest, I think that I spent more time trying to figure out how to connect things than actually building.

It wasn’t long before I realized this spacecraft was actually much more than “a few tubes” made into a spaceframe.  There were supports everywhere – all springing from the spaceframe at bizarre angles and joining up with things like the camera, the Canopus sensor box, the velocity and radar altimeter antenna and the fuel pressurization and nitrogen jet systems.  I spent many a Sunday afternoon measuring and cutting brass rods and plastic support beams and gluing them on.

Meanwhile, I had to build all the components.  The vernier engines, the camera, the altimeter antenna, the boxes, the omni-directional antenna.  I realize now that even a simple box is not all that simple!  A couple of times I neglected to take into account the thickness of the plastic – a fatal error (but it’s so thin…!).  Those 16ths of an inch add up…..

Over the course of several months I finally had everything built, devised clever (in some cases, not so clever…!) attaching mechanisms and was ready to go to final assembly.  But first I had to paint the bits.  Figuring I’d be clever, I primed everything and let that dry.  Then went the gloss white (let me state for the record that I hate gloss white…).  Masking (a nightmare – as you can imagine with all the protuberances) followed by silver.  Unmasking lifted some of the gloss white up – that I ended up touching up by hand. There are enough white war wounds on this baby for sure. 

As a point of note – there are no colour photos from the moon’s surface with Surveyor and Apollo 12.  Trying to decipher the colours from the black & white photos is mind numbing.

Household aluminum foil was used for the underside of the legs, and for the footpads and the 6 fuel/oxidizer tanks.  I think that turned out well.  It was the first time I’d done any foil work and this was a good test bench – there was no need to get super smooth results.

The sample arm and scoop worked great – the colour is a bit dark from what is shown at the NASM, but I can live with that.  The shape looks right to me, and it’s actually quite strong for being plastic rod pinned with aluminum wire.

I was lucky to find some RC propeller spinners to sub in for the vernier nozzles that came very close to the scale size.

I think the camera turned out really nice – lot’s of cylindrical-section visualizations during the construction but it is such a prominent element of the spacecraft that it needed to look right.  The nitrogen tank and the helium tanks look nice as well.  The valve assembly on the helium tank adds a lot.

Using the EVA Model’s insignia update, I converted a 1/6th scale Dragon Figures Buzz Aldrin figure to Pete Conrad.  The insignia update helps a lot in “busying-up” the figure.  I also added the OPS/PLSS antenna to Pete.  Finally, I added Pete’s checklist and tongs.  The checklist (made in Word pasted to a styrene sheet) is open to the Surveyor page with the associated “surprise” entry for Pete.

I dusted Pete up with some Bragdon’s grimy black weathering powder

The base is a 2’x3’x¾” plywood with a simulated moon surface made of Activa Celluclay (ready mix papier-mâché).  I added some very fine model railroad ballast (Woodland Scenics) and a couple of real rocks from the garden.  Painting was done with a little flat black followed by 3-4 shades of grey.

When I started, I wanted to be as accurate as possible.  As I progressed, I realized that compromises are necessary in order to retain some semblance of sanity.  I really didn’t need to wire and plumb the whole thing like it was supposed to work.  You just need to hint at it – and the mind’s eye fills in the blanks.  I didn’t need to worry that the vernier engines are missing a few pipes or that the boxes may be a half an inch off-scale when scaled up, or that the footpads are supposed to be truncated cones and not spherical underneath.  And I passed on trying to get the serial number information on the planar array antenna.

As with all monster scale models, the dilemma is where to put it – but that’s something I can work on in my spare time!

Graham Symmonds

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Photos and text © by Graham Symmonds