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Discussion Starter #1
Well, this is another of my rambling on threads. I have been contemplating two different methods of making the gear work on the J2.

The first is a "Jack Shaft" system. It's a threaded rod and moving block (which has threads to match the rod) and will take up very little space and not weigh very much either. This method allows the gear to stay where they are positioned with the power off.

The second method is a Lazy Susan type thing powered by one high torque servo. This method works with pulleys and springs and such and is kind of cluttered but is easier from a fabrication standpoint.

The next set of problems to address is what to do with the footpads and "hydraulic ram". The footpads need to be modified to stay aligned while pivoting, and the leg itself has to have a pivot bracket and control arm added which will add strength and because the part is made in a jig, the parts will all be interchangeable.

Last thoughts/ramblings...

Supporting the model. This will require some sort of attachment inside the model so as allow the upper hull to still be removed but hold the 3 wires, strings, or whatever tight. My model will have an RC receiver inside and a battery or two and some servos, possibly up to 3 of the pricey lil suckers.

I will start posting pictures as I actually go through the testing and construction of this project. I will also put the mechanical fusion core stuff in this thread so you can see a method to the madness.
 

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I figured I would see the landing gear thread move to this forum! lol The "how to put the Jupiter 2 back in the box thread can go on and on...but not a landing gear thread, only made it to twelve posts. Well I for one am looking forward to seeing your build on this Y3a!
 

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Discussion Starter #4
The rest of you guys can chime in with your 'working landing gear' photos n stuff. This isn't a contest. I HOPE we can all learn and try someone elses approach in the effort.

Question: Should model WHILE ON THE BOOM and with counterweight be able to support itself? This question is only valid IF I don't do the JackShaft.
 

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I'm subscribed to this one! This info will be easily adapted to any model for almost any purpose.
 

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...Question: Should model WHILE ON THE BOOM and with counterweight be able to support itself?...
I presume you're asking if the landing gear should support the model. Under the conditions you describe, what difference does it make? Manipulating the boom, one can simulate the shock absorber effect of the landing gear. But that can be built into a locking gear, also.
 

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Discussion Starter #7 (Edited)
For those who need to see the leg in it's various positions, for clearance, HERE IS a Toyroy/Y3a picture of the actual leg, photoshopped into 3 line drawings of the J2 hull to see the position of the 'real' Hero leg during retraction/extension.



And back of real HERO gear leg...

 

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Just did a bit of measuring and drawing using actual kit parts as reference.
Here's what I've found so far.

A simple hinge point at the base of the leg will not work.
The gear actually needs to move out and down.
I find that the centerpoint of the hinge action takes place about 1/8" outside of the hull.

Note where the bottom plate attaches to the gear assembly...notice the space ( about 1/8 to 3/16 inch) that appears at the mounting end of the gear ?
That's how far the legs will need to travel away from the centerpoint of the hull in order to retain the design stance of the deployed gear.
This means that some sort of glide rails will need to be used instead of a simple hinge.

More on this development as soon as I can create some detailed working prints.
Did you mean to post some drawings?
 

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Actually, I kinda jumped the gun...I'm gonna take a bit more time to sort it out....please disreguard that last post as the ramblings of a mad man :freak:

I did, however find that the post gets in the way of the gear going all the way in to their wells. May need to cut the slot in the top of the gear bay so there's more room. I don't think that there's room inside the model for the post to pass through into the upper deck as in the above diagram....can someone confirm ?
 

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Discussion Starter #11 (Edited)
The Hero gear wells are just the side parts. There is no wall at the back end, just a bracket the leg screws onto. The sides are not symmetrical either. each gear well side is different. I think it has to do with the internal attach points for suspending the model and the fact the pad door has to slide sideways. I plan to completly remove the original gear wall details off the hull and replace them with correct to the "Real" Hero ones.


There is also the "A" frame inside and over the wells which has that pulley wheel at the top. Those will not be reproduced in my version.


I plan on doing th pad doors just like the Hero. It IS the best solution to the problem. The rail will be brass and the parts will mostly be metal, except for the pad door itself.

 

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This is how it is, no joint at the pad, just at the stair case.
Wow, great illustration, Teslabe! :thumbsup: Question: what are the two holes in the strut for?

As for the hero pad, it is hinged parallel to the hinge at the foot of the stairs. You can see this in landing shots. As the gear begins to deploy, you can see the pad is parallel to the hull. It stays in the same relative attitude with respect to the gear leg, resulting in a toe-down position at full deployment, until touchdown.
 

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Wow, great illustration, Teslabe! :thumbsup: Question: what are the two holes in the strut for?

As for the hero pad, it is hinged parallel to the hinge at the foot of the stairs. You can see this in landing shots. As the gear begins to deploy, you can see the pad is parallel to the hull. It stays in the same relative attitude with respect to the gear leg, resulting in a toe-down position at full deployment, until touchdown.
Thank you toyroy, have no clue about the two holes......:confused: As for the pad on the hero, I would think it was setup to move forward and back but not side to side so it would move into the well without hitting the sides when it was retracted, just a thought....;)
 

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...As for the pad on the hero, I would think it was setup to move forward and back but not side to side so it would move into the well without hitting the sides when it was retracted, just a thought....;)
I agree. You can't actually see the pad connection to the strut. One might imagine it possessed the ability to adjust sideways- perhaps against the force of return springs. But, what alien spacecraft controller would give those nice Robinsons anything but a perfectly flat, conveniently marked parking space? :wave:
 

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The hero miniature had a different connection between the hydralic rod and the landing pad. The hero has a ball joint so the pad can swivel a bit.
 

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Discussion Starter #19
THAT is the MOST IMPORTANT THING TO DEAL WITH IN ANY WORKING GEAR. The footpads MUST, and mean MUST not rotate. They MUST stay aligned to the bottom of the leg. Use a very thin steel wire to 'make sure' if you need to.

Toyroy, you must have a spatial and mechanical aptitude thats off the charts.
 

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I shouldn't have said "swivel" - I meant that the pads could likely pivot so that they would sit squarely on the ground even if it's uneven.
 
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