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Jupiter 2 Landing Gear

10K views 107 replies 22 participants last post by  Jim C 
#1 ·
The landing gear is one of the neatest things about the Jupiter 2, so it should have a thread of its own. Some folks have asked about how to adapt their build to allow the gear to be changed easily from deployed, to retracted. Others are making functional landing gear.

Let me start off by asking: of those building functional gear, how many care about making the strut move, as on screen?
 
#2 ·
Well, that's one of those big questions, isn't it? I mean, it's built wrong to be functional (upside down), right?

I contend that IA would have preferred there be no strut, and the legs look more like the C-57D of Forbidden Planet or the rear stairway of a 727 (which was fairly new in service thus sexy), but the practical realities of the 'full size' set precluded that as an option.

but let's work with what we see. If the strut were flipped, so it COULD retract as it slid back in its (assumed) track, would that eliminate some of the space issues?

Just thoughts.
 
#7 · (Edited)
My 24" J2 weighs alonst exactrly 10 lbs. The landing gear is .040 styrene with a pivot of 1/8" styrene rod. All the landing gear does is keep the footpad in position. Virtually all the weight is borne by the strut. The strut is essential. I should do a moment of inertia calculation on it to be precise.
TR: the hero had a mess of wires and springs and pulleys inside. But I read that it was operated from the outside by said strings, "like a puppet". I've been trying to think of a way of making those doors slide up and to the side w/o all those fiddly bit. Getting the gear to go up and down is easy. Some kind of threaded rod will do the trick. But what if the threaded rod also engaged a circle for a brief time. The circle could have an incline around its bottom circumferance. Travel along the incline would raise or lower a captive attachment to the door. A stop point on at the ends of the incline would slide the door out of the way. The threaded rod would engage and disengage the circle at the beginning (or end) of raising the landing gear. You could make all motions work from one central source.
I don't know if I've described this terribly clearly. I don't know if my sketch makes it any clearer.
 
#11 · (Edited)
I'm thinking that the "upside down cylinder on the ram jack" are the struts like an aircraft. They would actually compress and absorb the shock of the landing. The Hyd. Sys. that actually raises and lowers the gear would be a deferent system altogether. The jacks would be up in the gear well and wouldn't necessarely be seen. Something to think about.

Jim
 
#17 ·
I'm thinking that the "upside down cylinder on the ram jack" are the struts like an aircraft. They would actually compress and absorb the shock of the landing. The Hyd. Sys. that actually raises and lowers the gear would be a deferent system altogether. The jacks would be up in the gear well and wouldn't necessarely be seen. Something to think about.
Yes, I think that's the idea. :thumbsup:
 
#24 · (Edited)
GeeZ...Sorry I'm late to the party. Great Idea ToyRoy!!

OK, here's my take. The rams/struts will work 'upside down' and the 'real' Jupiter 2 would have a pipe/hose combo that would connect to the rams cylinder end above the foot. No biggy. The sliding footpad doors is an elegant solution to the fact that the footpad can't pivot enough to fit flush with bottom of the leg. Again no biggy. I can buy it. This hydraulic system also seems to imply that the Jupiter 2 Fusion Core system repels from other objects in a manner similar to a helicoptor, not a system that positions the ship with enormous force and no 'play' - which is verified by the slow wobbling and pitching of the Jupiter 2 as it hovered inside the Derelict.

OK so to the model side of things. My 2 footers landing gear started life as the cast parts, but after I piled the 6 servos 3 battery packs and such I knew the legs wouldn't be strong enough. I re-enforced the legs with brass strips and using a welding jig, I silver soldered brass tube at one end, on a step up to get it to the height I needed to match the pivot point at the back of the leg. I also put a control arm at a 90 degree angle to the brass strip. this was glued to the topside of the leg bottom.



I cut down the oversize feet so they would fit in the clearances of the area of the footpad door. I used solder to imitate the ribs on the legs and hide the seam. I used brass rod and tube for my gear. The rams on my model are for show as I move the legs from the back. I used 3 micro servos in an intermediate link configuration to slide the footpad doors open. As I have a floor with holes cut for gear wells and access holes to get to some parts The area I had for the sliding footpad doors I used a rail and glued a plastic door beveled on the side toward the way it slides makes it work the same as it looks on TV but methods are different.



My model has brackets in thin plywood and maple blocks that support the lower level. The upper hull is not attached to the lower one, it just sits on alignment pins. 3 at the gear and 3 where the steel wire comes through the hull for it's overhead support. I have brass tube inside the holes drilled into the maple blocks inside the model. they sit flush with the upper hull with the tubes sticking up into the holes in the hull. I thread the wire thru the tube and make a small loop and crimp it. The loop goes around a screw head on the side of the same maple block this supports the model for any effects I may want to videotape - which is why I make these toys. I have separate system that spin the core lights and "V" and the 3 sliding hatches on the top are functional and the largest turns on the motor, lights and I have 2 settings. One for live/video effects, and a brighter faster setting for high speed photography. I still need to build a 16 foot 4x4 boom and head so I can have some real fun.

In operation the model sits on the end of the boom with about 6 feet of wire between the model and the boom head. The boom head needs to swivel and rotate and the boom needs to be piloted at the control end at about 6 feet up to allow for swing and counterweight stuff going on . Lets say you are doing the derelict shot. The boom is off to the left behind the camera. you turn on the bright settings and RC equiptment and get out of the shot, you slowly move the model into the light while slightly pitching and rolling the model while it sits about a foot off the floor. slow it to a stop and CUT! Next shot from down on floor looking up at bottom of saucer. ROLL! slowly slide the pad doors open, count to 2 and lower gear and slowly set model on floor.....fade out...CUT! Next, with model still going, pick it up and rotate it so main viewport is facing directly at camera. set down.....ROLL! Slowly raise model while retracting legs and allowing doors to slide back into place....CUT! Zoom in camera to viewport , get set and continue..ROLL! slowly rotate model so window passes through scene and continue to move model out of light. CUT!!! turn off lights and motor, turn of RC. rewind and watch. I will try to get some video of my Lunar Models mechanics in operation to post here or Utoob or somesuch. I wish I had used a jackshaft on that model but I just couldn't find all the parts or even a machinist to make a part or two. So my model weights a bunch. Too much to trust it to monofiliment. You get to paint the wires on mine.... I use a magic marker to make the wire black but for light blue you'll need to paint 'em. My Jupiter 2 uses flat sheet plastic sheet for the windows and small brass "I"-Beam stock for the window frame so it looks like the Derelict era Jupiter 2. The photos are still in my album, feel free to look! even a teeny bit of video of the core lighting test.



VIDEO of fusion core light test
http://photos.hobbytalk.com/data/509/LM_Jupiter_2.mov
 
#26 ·
and just to stir the pot, I have another thought.

The landing gear on the filming model may not have been designed to retract, or better to say, retract seamlessly.

The main engineering may have been to drop the gear, because that's all you need to do. To show the gear retracting, simply reverse the film. I seem to recall a few shots of the fusion core 'spinning' the wrong way.

It's a common concept in effects filming. Like turning a model upside down as well as the camera and pulling something up out of it, instead of the more complicated dropping it down. All that matters is how it looks on film.

Again, just a thought exercise.
 
#28 ·
OK...The Hero in operation...

Had a small push in push out switch to power on the self powered effects (Lights and mechanical fusion core). Gear was powered from the 3 support wires and had a plus minus and ground. sliding hatches were for access to mechanics on hero. Gear was wire/pulley system. The gear was designed to lower under tension, with the footpad doors moving out of the way first, followed by the legs dropping to a preset endpoint. The model, when set on the gear tightens up the pullys and wires and it makes the model appear to rest down a bit on the gear. There are shots of the Jupiter 2 lifting off and smoke is clearly seen going in a normal way while the J2 lifts off and retracts the gear upwards. This verifies the gear works both directions. as the model took a beating during is filming career the gear lowered a little more jerky each time after the end of year 2. By year 3 they were landing it on the Fusion core and that explains the missing fins. I always wanted t see all the original Gemini 12/J2 crash scene at the pinnicles. All the behind the scenes. did they trash a 4 footer in the process? How long was the run from one end to the other 1000 feet? How in the...did they do that shot. I know they used one model and multiple cameras in different positions. They put the outside clips out of order to make you think otherwise, but go back and look.
 
#29 ·
Fair enough on the retraction issue. I would assume that over time, under the exposure of the studio lights and the day to day handling the hull might flex a little, mounts inside might work loose a tad, and thus you get the 'not quite all the way up' of that one episode.

I've always wondered how you string a Lydecker rig. If you have holes (and probaby tubes so the wires don't slice your model like soft cheese), I would assume you have to thread the wires thru, then run them down to the other end and tie them off. or something. And while it did have to be as light as possible, it also had to have SOME mass to it or it wouldn't slide down the wires convincingly. I tend to agree that flying the 10 foot ship down a Lydecker rig probably didn't happen.
 
#30 ·
I have an idea they used pulley wheels and that the models support wires didn't slide thru the model, but rolled thru. This is less friction, and allows for a more crane like operation not just a taught wire the model slid down. I think the Crash was done with one big cable thru the model on wheels, and another cable attached to the front and back which works like a clothes line with the model being pulled back n forth on a winch. At least they could slow it down. You'll be amazed how much drag a tube has when trying to slide a 40 pound model.
 
#32 ·
Well even my 1 foot model, with nothing inside was too heavy for a 300 foot run on steel Control line airplane wire running through a brass tube glued to a straight edge on a piece of 1/4 inch ply to prevent deflection. I ended up putting little brass pully wheels at the ends of the tube for less friction.
 
#35 · (Edited)
If I'm not making a mistake, I remember have read somewhere, in one of the various threads that poped up in this forum after the announcement of the Moebius J2, that the backs of the 3 legs would fit and match exactily the hull surface around the landing gears openings.

Instead, the sequence of images atached shows that the back of each leg doesn't do that, but lies over the opening edges, being a bit larger than the landing gear bay opening.

However, the pad door aparenttly do it, making then two movements: one of them sliding lateraly and the other moving up/down against the hull, matching the hull surface.

Am I correct?
 
#36 ·
...the back of each leg...lies over the opening edges, being a bit larger than the landing gear bay opening.

...the pad door aparenttly (makes) two movements: one of them sliding lateraly and the other moving up/down against the hull, matching the hull surface.

Am I correct?
I agree. Later in the same episode("The Derelict") you can better see how the pad doors move, after the ship lifts off.
 
#37 · (Edited)
Mechanically, the pad doors are intact on the Hero!

In the Jupiter 2 Autopsy the doors are slid back n forth on the rail.



the door itself is the cut-out/footpad door itself with a button sort of projection sticking out from the center. It may have a square shaped post to keep the door aligned. the bracket it attaches to slides on the rail which is glued or otherwise attached to the hull. The bracket has a slot where the button slips in so the door can be slid sideways on the rail and up and down because of the play built into the gap between the button and the door.


And heres a look up the gear well to see what it looked like from the other side...





Heres a look at the back of the gear leg so you can start to see how stuff was rigged up:



Using a photoshopped leg, I placed it in the model to see the clearances.

 
#38 ·
So, compared to the hulls surfaces we have:

3 legs (raised)
space pod bay door (depressed)
shields of the auxiliary control window (depressed)
chariot ramp (matching hull?)
2 port holes (depressed)
air lock door (depressed)
3 hatches on top hull (depressed)
not to mention the main window shields and the several retrorockets "holes".

Apparently the J2 hull lines were not as clean as I thought. Of course, nothing to be compared to the extremely complicated exteriors of all the "hollywood spaceships" after the 2001 - Discovery advent.
 
#40 ·
YEAH!! As Long as ............ (L0L)

The choice - IF you are doing something with the gear is :
Working or just moveable?
powered or puppet?

The "Hull lines" do seem to have changed from the elegant saucer in Derelict, to the piece of crap in "Junkyard in Space" slamming down on the core... after the pod was added. I believe they used the same upper part but fattened the lower level between years 2 and 3. This may have been at the same time repairs might have been needed to the hull after it dropped off the boom and shattered the original mechanical core. from then on, the chaser from the pod dropper was used on both models.
 
#41 ·
I saw a PL J2 lower hull builted in flying position (I don't remember where) with the landing gears backs raised. Man, sometimes I don't know what is better: accuracy or just impressions. After all, excepting for the rare close scenes of the landing legs lowering, how many times could you note these raised details?
 
#42 ·
As a kid, I thought the gear backs closed flush with the hull, and I thought that was so cool. But then, I also thought the bottoms of the landing pads were flush with the hull bottom. Later on, watching the pad doors move, I much prefer that action to my earlier (mis?)-impression. But I still prefer the gear backs to close flush with the hull.

I just prefer the ship to have clean, simple lines. But I also like the gear to work as it is seen onscreen. That involves the gear leg motion, the strut motion, and the pad and pad door motions.
 
#47 ·
WRONG!!!!

You need BOTH correctly constructed gear and the rest of the stuff too (gear wells, area for mechanics if any are to be constructed.

You need to settle on a method to raise and lower the gear before you make the gear legs so you'll have an idea on whats needed for construction of the legs.
 
#48 ·
I plan on making mine functional as if it were a real ship. I'll try to duplicate the beauty of the show but my intent is to build something that could be the real deal in the near future. I'm really intriged by Y3a's work. I defenitly need to pic his brain on some of this stuff.
 
#49 ·
I'm really intriged by Y3a's work. I defenitly need to pic his brain on some of this stuff.
Well Ax away!:wave: I can discuss the mechanical side of something as simple as the Jupiter 2 gear all day long! I hit the site about 10-20 times a day depending on how bizzy I get. If you've read my posts you'll know I'm a purist with the Jupiter 2(s). All 3 have appeal. I like the 4 footer best, then the small "toss around" version, and lastly the Set/Full size mock-up. They are a different diameter than the models so I group those as one version (straight sided, different gear, non-spinning bubble, small non-finned fusion core) The models are different ships, with the 4 footer being THE Jupiter 2, and the small model IS the Gemini 12. So what if a piece of reflective tape was put where the lower level viewport was to complete the illusion. It's visible as the lil Jupiter 2 comes into the Derelict, and one of the wires brushes the Derelicts door segment and you see the model roll a bit.

I 'think' the lil Jupiter 2's fusion core spins the opposite:rolleyes:way from the 4 footer. Hmmmmm.........

Does anyone have photos of what kind of boom supported the 4 foot Hero? I read in 2 different places that it was a 50 foot mike boom, usually bolted to the stage floor. This would have had an operating/moveable head.
 
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