proran

@Didumos69 First of all, thank you for bringing that topic up. For me, there is no question about practical use of such connections. Triangles are very stiff structures, so every large construction will benefit from them. You can see angled liftarms in some official TLG sets, used to reinforce the structure. If we are talking more specifically about these smaller ' Pythagoras ' triangles, the perfect illustration is your Rugged Supercar (it is brilliant, b.t.w.). And I have an example too. Right now I am working on a Unimog. Unimogs have that famous double-S shaped frame. If you make this frame using single layer of liftarms, the chassis will be very soft ( and you won't need a suspension in that case ). So I am using triangles to reinforce the frame around the bends: It is old WIP picture . Right now I've switched to the legal ' Pythagoras ' triangle and the frame looks better. Can post image later. Updated frame sketch: But I would agree, that applications for connections other than this simple 'Pythagoras ' triangle could be not so easy to come up with.

I should say, I've been skeptic about trailer MOCs. For me, for some reason, it always been an attachment, something minor and of second importance. I know where are some great trailer MOCs out where from very respectful builders. But they was just not my cup of tea. Until that one. This is a real beauty! Rounded shape and Tumbler tires makes this thing to stand out. I appreciate the effort on that rounded line at the middle of the bed, made from red 2L pin joiners. I like how the level of detail matches that of the Claas Tractor. And functions, of course, are brilliant. The only little tiny negative comment I have, is about that fake cylinder. With lowered bed it not very noticeable, but became a really eyesore, when it is raised. I would remove it, and just assume that trailer have another type of the rising mechanism. But this just my opinion, and I understand the reasons to include it. Again, outstanding job! Thanks for sharing.

This is a really nice backhoe! It looks a well thought through and balanced. I like the its 'utility' look. And the outriggers are great, well worth the efforts.

That is gorgeous! This is the level of performance I would like to see in a Remote-Controlled MOC. Perfect balance between speed and torque. The key is, I believe, the right selection of size and motors. Really good job! The video is great too. I love that shot with the slipping wheel in a cloud of dust. Beatiful detail! I will double the agrof's question about the custom differentials. Thanks for sharing.

There are a lot of great entries. This is one hell of a contest! 1: 1020: 621: 417: 332: 215: 1 Thanks Jim for organizing it!

Hi! I am sorry for bumping this up, I just want to share the last pic. I have disassembled the thing, and here is the bill of materials for the drivetrain: I have one word for it: ! ! ! F R I C T I O N ! ! !

Oh, these liftarms. I should have studied that picture more carefully. Nice solution! Thanks for the reply!

Finally, someone have done it legally!!! Congratulations! I have tried to do it some time ago, but completely failed. The main problems were the high resistance of the valves (I used the new ones) and high required stiffness of the frame. If the cylinders are not perfectly synchronized they will twist the frame into a knot. Congratulations on your achievement. It is a Technic marvel!

Wow, that contest really sparks the creativity out here! I don't even know what to say about the model. For sure it is complex Technic build, but the subject gives you no chance to take it seriously. Incredible work!

The contrast between the modest look (although I love that grille!!!) and the brilliant functions is just incredible! The container tipping using one cylinder is ingenious! And it is actually works. The model is full of nice solutions, e.g. the scissor mechanism for the compactor and the suspension. The only minor downside is the filminess, but I understand this is a compromise in favor of functions. Great work!

Wow! This is incredible! The thin cylinders really shine here. I love these loops you've used to route the tubing out of the cylinders at the front bucket. I was looking for an elegant solution for that for a long time and yours is perfect. Legal and compact. And the color-scheme! It shouldn't work, but it does. It is also nice to see a backhoe with the front and rear wheels of the same size for a change. Could you expand on that not-independent double wishbone suspension in the front? I understand that it behaves like a rigid axle, but I would really like to see the details of the implementation. Thanks and congrats on a great model!

This is neat! It looks so organic. The Technic set as it should be: clean appearance and some nice engineering underneath. The logical solution at the scale would be to skip differentials in the front. Good job on pushing it through. I am looking forward the video. How these 12T bevel gears in the front axles manage the torque of the XL without a rigid bracing? Based on my experience nothing but the dedicated brackets can stop them from slipping.

Thanks for all the replies! Wow! TLCB! That's cool! Thanks to whoever suggested it! I should note, that while I was building it, Mecalac had released an updated version of 12MTX. I always new it is easier to build vehicles in real life, than in bricks Here is the comparison to the old version I was referring to: The chassis is too high by couple of studs, and overall proportions are a little bit off. But I've tried hard. At the end of the project I had some fun with SNOT building in the rear for a change from all these gears. I am working on that. But, again, slowly . I hope I won't be the one-moc-builder, how Sariel called it in one of his interviews.

Thank you, guys, for all the comments. I really glad I've got such a nice response. To hear such words from the Eurobrick's PRO's means a lot to me. Thanks. Well, actually the model started at another continent three years ago. The first draft of the arm flew 8000 km to Canada in my backpack. Just couldn't force myself to disassemble it! Wow, even if a little, it is still a great honor for me Thanks.

That's a good argument. I think you are right.

No, no, no. Probably, I didn't get the feedback, but I cannot say I have no contact with the community. I learn a lot from Eurobricks, Technicopedia and all other resources. Basically the community was the main reason which keep me building. About the genius thing, it doesn't feel that way. I guess, if you a genius ideas just spark in your head. But in my case it was failure after failure. You can call me patient :) I honestly think that building to TLG standards requires more skills and efforts. To come up with the idea is one thing, but make it work reliably under all circumstances and make it fool-proof is a totally different story. Okay, I start going off-topic a bit... That's right, thanks Lipko. The problem here, is that the axle in this case is supported only at one end. So you have no connection between the axle with the clutch and the axle with the clutch gear. Theoretically it should be a problem, but in practice they align perfectly, and I never had a problem with it. Speaking of illegal connections, this is a bad one....

Oh, there's a number of them, yes. I should have mentioned it. The most anti-purist thing is the aluminum foil used to connect old 9v battery to the receiver. I couldn't accept it for quite a while, but at the end I needed to decide between realistic cabin or purist solution. Looking at the final result, I can live with it. Other than that there is parts under little stress or rubbing each other here and there, but nothing what really bothers me. The thing doesn't stand to the TLG standards, that's for sure. I guess this is next level of building skills. I know some of you here guys do that, but I am not quite there yet.

Thank you for all the kind words! JGW3000,I couldn't stop thinking about your userpic, while looking through the windshield: I couldn't turn it the right way, since the polarity will be reserved. About the passing the functions through the turntable. Here, three functions are passed through the body articulation axis. I believe, this is what you mean. Still only two functions are passed through the turntable. I am sure it is impossible to pass three through the traditional turntable while maintaining 360 slewing. Zblj have come up with ingenious solution in his crane truck, but with the slewing limited to 180 degrees. I believe, you can try it with the new rings from 42055 and using the large turntable to pass the third function. Yes, I frightened by it too. It doesn't feel right. I promised myself, I will try to avoid such a mess in the next MOC, but now looking at the WIP I have, it seems, I subconsciously like it. Yes, I like them too. They look nice in the render, but actually turned the structure under turntable into a complete mess. But this is the shortest solution I have found to pass the drivetrain into the turntable. Everything more traditional will make the wheel base two long. What a compliment! Thanks. More of that:

Hello all! I was reading the forum for quite a long now, but it didn't feel quite right to post, without proper introduction. Well, finally, let me present my first MOC here on Eurobricks: Remotely Controlled Mecalac MTX Here is the quick video showing the operation: More Pictures: Description Statistics: Weight: ~1500 g Part Count: ~1400 Dimensions: L x W x H (without boom): 300 x 140 x 220 mm Remotely Controlled Functions: Driving & Articulated Steering Continuous 360 Slewing Elevation of 1st boom section ( mLA) Elevation of 2nd boom section (LA) Sweep of the 3rd section (mLA) Elevation of the 4th section (mLA) Articulation of a Bucket (mLA) Power Functions components: 3 x L Motors 1 x Servo Motor 1 x M Motor 3 x IR Receiver 1 x AA Battery Box 1 x 9V Battery Box The color-coded render showing the drivetrain: The functions are distributed by two gearboxes - one located in the chassis with two clutches, and one in the superstructure with three clutches. The chassis gearbox is switched using the M-motor through a worm gear. The same motor controls the deployment of outriggers (Similar idea is used by Pipasseyoyo in his dump truck http://www.brickshelf.com/cgi-bin/gallery.cgi?i=6254101). When the outriggers are raised, the two L motors in the chassis provide driving and steering. After the outriggers are deployed, motors drive two clutches in the superstructure gearbox. The third clutch is driven by the L - Motor located in the driver's cabin. The superstructure gearbox is controlled by a Servo. To make it work I have to get rid of most beloved Servo feature - return-to-center. Otherwise, the gearbox will be switched to neutral, each time the controls are released. The solution turned out to be pretty easy: One may say, that using the M-Motor for the gearbox would be easier and more compact. But I like the limited degree of rotation provided by the Servo, so I don't need to stop the motor precisely at the right moment. And, to be honest, after I came up with the Servo solution, I liked so much, that I'd decided to implement it besides some shortcomings. As a result, 8 functions are driven by 3 motors. But the controll requires some practice, since you need to switch the gearboxes often. And as you can see fro the video it is extremely slow. So you can't actually 'play' with it. But it works. About the development process (you can skip it, if it is enough reading for you; I haven't found a way to make a cut) After I had completed my first working MOC - a Unimog truck, I was looking to build something more technically complex, so I can put to a good use all the gears and u-joints I have accumulated in my parts collection. Well I have achieved that. In the course of the project I have ordered the additional u-joints together with a lot of gears four times, and then a little more. The inspiration came from the ingenious brick-sorting excavator by IbrahimFitzGibbon. About the same time I came across Blackbirs's Technicopedia, and was impressed with the old sets, where often several functions will be controlled by a single motor using some crazy switching mechanism. And when while on trip to Germany I saw it. Mecalac 12MTX excavator working on a narrow street in all its glory. This is it. Compact, complex, with tons of functions packed in a small space. I knew, I must build it. After I scaled the blueprints to the medium wheels I had at the moment (68.7x34R), it was obvious that the implementation at this scale will be almost impossible. Will all the motors and gearbox clutches in place where was almost no space for the structure or drive-lines. So I decided to go for it. It was extremely hard. You know, when you are completely sick of it, but something keeps you going. Every time I would start working on a new mechanism, the first version will be two or three times bigger than it should. And when after dozens of iterations it will fit, but won't work. So optimization, optimization and optimization. I have 58 LDD files for that thing, but they only reflect major changes, when I needed to start from scratch. In total it took almost three years. The main challenge was the boom. Mecalac boom have five articulation points instead of three in a traditional excavator. That means that I needed to pass four drive lines through the first rotational axis and three through the second one. Anyone who built the excavator knows how difficult it it is. I wasn't able to use u-joint for the first two axes because of the limited articulation. Additional challenge was the implementation of the third articulation point, since the axis of rotation is for that one is rotated at 90 degrees to the previous axis, and they are only few studs apart. Figuring out the way to twist the axes took a loong time. At the end I am satisfied with the result. But not more than that. It works. But you can't play with it. Because all the arm functions have a very long drive lines with a lot of gears, I had to heavily gear it down to be able to overcome all the friction. So the arm functions are extremely slow. But all the ideas work. I I really love same places in the model. Like the Servo with no-return-to-center clutch, chassis gearbox switch coupled with outriggers deployment, three u-joint passing the chassis' articulation axis at angles. There, I finally used that teeth on the old gearbox gears. Coupled with old style half bushes, it allows driving the axle directly (see the orange drive line below). And I hate Yellow color now.