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[Vee]

Is there some awesome Lego engineer here that could solve a problem for me? I am trying, but so far, no good.

I want to find a way to, as I pull the red axle to the LEFT, it will turn on the light. I have not tested but I see that the light brick has a slope in its "button" and that probably, when I pull the red axle to the left, it will make that button to go down, hence turning on the light, but this is not a good solution because the axle will not come back automatically to its resting position, I will have to push it to the right to turn the light off and I wanted the axle to come back to the right when I stop pulling it to the left, by using the movement of the button itself (that always wants to go up) to move the axle to the right, once the force applied to it stops. Note that the red axle does not necessarily need to rest in the current position, it can rest at any position as long as it is still fully contained between the two 1x2 bricks with a hole.

<LXF file>

Thanks for any help.

[jodawill]

I've done this before in an alien vehicle I made. I just put the light brick with the studs up and had the axle go through a brick with an axle hole, not a pin hole.

[Vee]

But isn't the light of the light brick kind of directional? I want its light to light down; if I use the light brick with studs up, light will have focus to the side, isn't it?

[dr_spock]

You stick a ball with axle hole on the end.

[Vee]

You stick a ball with axle hole on the end.

Sorry, which is this piece? This one?

[dr_spock]

One of these guys: http://www.brickset.com/parts/search/?query=32474

[Vee]

It doesn't look like it would work. It is too big.

[Junpei]

Do the bricks have to be in that exact layout? I'm sure I could think of something.

TLH

[Wodanis]

Why not change the design and use a technic plate that has holes on the ceiling, then put a smaller axle through it? That way the direction is maintained. The family house set from last year did something similar. Maybe looking at the instructions will help? http://www.brickset.com/detail/?Set=31012-1

[Junpei]

I finished it! Here it is:

View from the other side:

Lit up:

It fits in a relatively small space, and can be completely covered with plates on the bottom:

All the parts used are relatively common except the 1x5 liftarm and 14 gear. And yes, it does return to center.

Hope that helps!

TLH

[Vee]

Looks awesome, if I could just figure out what you did from the pictures ...

Well, I _am_ trying.

Why not change the design and use a technic plate that has holes on the ceiling, then put a smaller axle through it? That way the direction is maintained. The family house set from last year did something similar. Maybe looking at the instructions will help? http://www.brickset....il/?Set=31012-1

Changing to make it come from above is more complicated. Has to be as shown and, to make matters worse, the space around is restricted, more than shown in my sketch.

Do the bricks have to be in that exact layout? I'm sure I could think of something.

I believe so. What I am trying to do actually is to add the light to my bricklinked Ole Kirk's House. If I can do it, then I plan on adding some interior to it. It already has landscape in the outside.

Here is the full scenario.

[Hrw-Amen]

How about rather than having the brick the right way up, you turn it upside down. That way the axle could still go into the button to turn it on and off an the light would still be directed down for the most part like you want. You would just have to rig some way of holding the light brick upside down, but will all the brackets and modified bricks available that is not something that is too difficult.

[Gnac]

If you don't mind changing the structure slightly, this could work:

The end of the yellow part should be able to clear the edge of the lightbrick, enough to push in the button.

EDIT: I also suggest swapping the black 1x2 brick in the middle for a 2x3; placed such that it is right above the yellow part. This should stop the whole axle from rotating and fudging the mechanism.

Edited January 13, 2014 by Gnac

[Vee]

I found the way below. I lowered the fx light brick the distance of on plate, then an "L" shaped lever should do the trick. I don't have the pieces to test in real life yet.

Another angle:

If you don't mind changing the structure slightly, this could work:

EDIT: I also suggest swapping the black 1x2 brick in the middle for a 2x3; placed such that it is right above the yellow part. This should stop the whole axle from rotating and fudging the mechanism.

I am trying to avoid changing the structure because I am trying to keep as much as like the original, this is a MOD of a Lego set. By doing the way I showed, I am only changing one 1x2 brick, from 1x2 brick to 1x2 brick with a hole and all the other parts are additions, not replacements neither relocation.

[Gnac]

I found the way below. I lowered the fx light brick the distance of on plate, then an "L" shaped lever should do the trick. I don't have the pieces to test in real life yet.

Unfortunately, this doesn't work. The force from the red axle pushes the L-shaped beam against the two jumper plates holding the lightbrick, preventing it from swinging down to the button.

Removing the plate below those 1x1 technic bricks gives the L-beam better clearance.

Edited January 14, 2014 by Gnac

[Vee]

Damn it! You're right. I simulated the turn in LDD and also found the problem you described.

Removing that plate is problematic, it sits on top of some "beams", in a perfect position. I had thought also of lowering it, not to avoid this problem, that I had not foreseen, but to make the leverage from the axle to the L-shaped piece stronger. If the axle hits the L-shape piece higher, the better, less force needed to push it. I will take a look at the real situation and see how to lower that plate. DANG!

Well, just found one solution but I don't know if it's good.

I just removed the two 1x2 with one stud in the middle and placed only one horizontally. Now, the light brick is held by only two studs but the two in its center. Do you think this is strong enough?

[Vee]

Afraid that that light brick can "pop out" if too much force is applied to the axle, I added this "reinforcement". Looks like a hack but should work. The blue parts should actually be transparent clear.

[Vee]

... Removing the plate below those 1x1 technic bricks gives the L-beam better clearance.

I removed the plate below, as a test, in LDD only, but LDD tells me that if I do that, the light brick will not fit. In reality it may fit if the L-shaped lever pushes down the on-off button not enough to turn on the light. Did you test this possibility? If yes, did all fit all right without turning on permanently the light? Thanks!

Uhmmm, me dumb dumb. It is better without the plate. The two 1x1 bricks with a hole can just sit where the plate was connecting and the axle needs to be 2M longer. But I have the collision problem above, light brick x L-shaped lever.

Edited January 14, 2014 by Vee

[Junpei]

Have you tried the one I made? It's already reinforced, I've used it at least 20-30 times only held by one hand, and it still stays together.

Good luck,

TLH

[Vee]

Have you tried the one I made? It's already reinforced, I've used it at least 20-30 times only held by one hand, and it still stays together.

I have two problems with your solution. First is that I cannot replicate it, because I cannot figure out what you did based on your pictures. I look at the pictures, look, look, look, I have even cropped them, resized them to make them bigger and increased exposure to see behind the shadows, but still I can't figure it out. There are parts there that I can't see and also, I am not versed in Technic parts, I am like a rookie. So it is certainly not your fault but mine.

The second problem is that, based on what I could see, I am afraid it will not fit. If you see my sketch, note that the axle that pushes the button is aligned with the light brick. Your solution makes me believe it is not. You moved the block to the side. What happens is that in my real scenario (there is a link to a pic of it some posts above this), the axle cannot be relocated; the brick maybe could be relocated, to the side, but I am afraid I don't have all the necessary space around to do so, as required by your solution. As I mentioned in a previous post, there are more space restrictions around the whole thing than what it is shown in the sketch.

To really test and see if your solution would fit in the real scenario, I need to be able to understand it, replicate it, and I am not.

Also, note that I do not work with real parts, I only work with LDD, because I don't have all the needed spare parts. I do the planning/design using only LDD then I buy the parts, after I think the thing is done.

Edited January 15, 2014 by Vee

[Vee]

@TwentyLeggedHen: Well, after some more attempts, this is the best I could come up with based on your original design; some parts are missing but it doesn't matter, what matters is how your lever system works. I have used some different colors just for the sake of making it easier for me to identify the parts.

http://prntscr.com/2jl68b <LXF File>

My questions:

- Is the yellow Technic 5M Lever, and everything connected to it, just an reinforcement?

- In LDD, the green Technic 2M Lever does not connect to the green axle, as I assume it is supposed to; I then assume that due to some slack, this connection is possible with real bricks, is that right?

- it works like this: you push the red axle, it moves the blue cross block ahead, taking the green axle with it, the green axle moves the green 2M lever that moves the blue axle that moves the lime 2M lever that TURNS the dark green 2M lever down, pressing then the light brick button. Is that right?

- What is the 14 gear for? I couldn't see a reason for it. Is it being used just as a spacer? LDD, as far as I can tell, does not have this part.

- What is that medium bley bush for cross axle doing near the 1x3 black flat tile, in your original design? I can't see that side of your build.

- You mentioned a "1x5 liftarm": is this part the same as the Technic 5M Lever?

If I can understand how your mechanism works, I can try to implement it and see if it brings better result than what I have now.

Thanks.

Edited January 15, 2014 by Vee

[Junpei]

Wow, awesome job adapting it to LDD! Sorry I didn't get better pictures. To answer your questions:

-Yes, the 5M Lever is just a reinforcement.

-The only inaccuracy (and I don't blame you for it) is the lime green 2M lever is supposed to be a 3M lever with the following pin/axle holes: + o + It should connect then. The blue axle should then go through the pin hole with a half bush behind it.

-Precisely.

-You are right- the 14 tooth gear is just a spacer. It is just under a 1/2 of a stud wide, and because of the angular displacement of the light green liftarm, I used that. Unfortunately it doesn't work with a normal half bush.

-Again, sorry about the pictures, it's for reinforcement with some technic bricks- it's actually the 2M pin with stop bush. The 2L pin part is pushed through 2 bricks.

-Yes, it's the same part.

I really appreciate your hard work adapting it from my crappy pictures, and you did an awesome job managing to figure out how it works from just the pics.

Thank you, and I hope for the best!

TLH

[Vee]

Thanks for the clarifications. I will now study your answers . I just found a flaw in my solution. I was counting on having the light brick held by its two center holes, as LDD allows me too. However, I decided to do some real testing here, I disassembled partially my Family House (31012) to get a light brick, and I found that my Quad Bike (8282) has the L-Shaped lever that I need. Well, I assembled a structure to simulate what I will have, did all things needed and then, when I tried to connect the light brick to the 1x2's with a hole in the middle, it would not connect! To my dismay and sadness, I found that the light brick does not have those two holes as a perfect circle, like all bricks. Because it has the small screw right there in the center (to allow replacing the battery), the two holes are not circular and nothing will connect to them. DANG!

As for your solution, I can only test in LDD since it uses pieces that I don't have.

[Junpei]

Yeah, that always bugged me, too. I tried to build a TARDIS with a light brick in it once, and I had the exact same problem.

Hope you find a solution, I will also try to figure something out with more common parts.

TLH

Edited January 15, 2014 by TwentyLeggedHen

[Vee]

I moved a little the light brick and the L-shaped lever works.

Pic 1

Pic 2