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This is just insanely good... I tried to improve the 42079 and am now just drooling at the level of precision here... :wub:

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Un très grand merci @nico71! I very much appreciate it when expert builders like you create alternative sets with instructions. It adds value to the existing set, it functions as inspiration + it is easier because you already have all the needed bricks. Very much looking forward to building this.

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Thank you for the comments :)

 

Indeed, creatin a B (or C or D) model is very exciting and challenging, and it worth for the instructions.

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New creation : 

A reproduction of Citroën Mehari in 1/15 Scale, featured independent suspensions, steering, working doors, tailgate, bonnet and removal hood, with building instructions.

Lego-Technic-Citroen-Mehari-5

 


Context

After my Mini Citroën 2CV in Lego, many people asked me to build other Citroën models, for instance DS, BX, SM but also (and mostly) Mehari. After some months, a fan asked me by email to design him a Mehari version of the Big 2CV I designed year before, which convicted me to work on the Citroën Mehari version and make building instructions in order he can rebuild it. I have chosen to not go for a big scale because of the amount of needed parts and because I wanted to build in different colours. That is why I have chosen a small 1/15 scale for these Mehari.

Lego-Technic-Citroen-Mehari-4


Functions

The functions are rather basic in this scale, but are mainly focused on playability. As on my previous Mini 2CV, the Mehari version is equipped with independent suspensions with metal springs located in the floor. It enables to have the same bouncing suspensions as real. The steering wheel is connected to the steering using U-joins and operated the steering by a lever plus a link 6L. An other link 9L connect the two wheels.

Lego-Technic-Citroen-Mehari-16

The next functions are more about design functions. In deed, the doors and the bonnet can be opened to reveal a detailed engine (but not working), which can be removed easily to see how the steering and suspensions work. The rear is equipped with a spare tire accessible by the rear tailgate which can be opened too. To finish the upper hood can be remove easily with centring pins on the middle near the pillar and axles at the rear, in order to have a better playability or realistic look.

Lego-Technic-Citroen-Mehari-17


Design

The design was the most difficult part here. The mini scale has the advantage to enable less details for the users, but need to have iconic details and good proportions in order that people forgive the approximation but recognise easily the model. I have started to work on the side of the car, trying to reproduce the shape of the rear wheel arch. I also wanted to build something sturdy and with cheap parts, that is why I have chosen a combination of a panel, beam and tiles. The other difficult part which has reduced the available colour for this project were the doors. I wanted to reproduce the shape of the doors and the difference of height between the doors and the bonnet which are iconic. I managed by using Bionicle tooth and a beam positioned with an angle. It doesn’t fit perfectly the original shape but it enables to have a sturdy design and smooth side.

Lego-Technic-Citroen-Mehari-12

The other difficult part was the fact that the rear wheels are covered by the mudguard and go in the bodywork, as on the 2CV. I was easy to do on the 2Cv because the trunk was closed and not visible, therefore I could hide the wheels inside the wheel arch on the each side (which reduced the room in the trunk). But here I could not make the same because it would have reduced the size of the rear trunk and would not fit the proportions. that is why I searched a way to have a thinner box as possible, by using plate and tile placed by half pin.

Lego-Technic-Citroen-Mehari-8

I finished the design by making the interior and the bonnet which was easy to do with the connectors and beams. The front is rather simple also except the lights which use 1/2 gap technique to fit correctly the lights and corner lights around the front grill and the bonnet. The only regret I have is to not be abbe to put end stops on the suspension and steering in order that the wheels do not touch the body when you turn and press entirely the suspensions. It was too hard to fit at this scale without reducing too much the travel of suspensions.


Pictures and video

 
 

Building Instructions

An important point of this project was to create building instructions. That is why I focused myself to use available and cheap parts and find 3 possible versions without major changes in design : red, white and orange. You can see below the three versions with :

  • A link to Rebrickable inventory
  • A link to bill of material as image

Red Version

lego-mehari-2

rebrickable_logo.png Want to know if you can build the red version of the Citroën Mehari ? Click here.

Bill of material in picture file (red version)

 

White Versionlego-mehari-3

rebrickable_logo.png Want to know if you can build the white version of the Citroën Mehari ? Click here.

Bill of material in picture file (white version)

 

Orange Versionlego-mehari-1

rebrickable_logo.png Want to know if you can build the orange version of the Citroën Mehari ? Click here.

Bill of material in picture file (orange version)

You can see example of the building instructions and buy it for 7.5€ on my website.

 

I hope you enjoy, feel free to comment or ask questions :)

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I really like Mehari. It reminds me on Le gendarme de Saint-Tropez :wink:

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I have just finished your D model for 42082. The Heavy Forklift Truck is massive, looks great and all functions work smoothly. What is more instruction is very professional and building process is quite challenging - that's how I like it.

 

I recommend it to all fans of Lego Technic who enjoy not trivial building process and outstanding results.

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I have a small question to the specialist of clock.

I am building a clock which is a bit special and can not figure out to find a name !

You can see it in functioning here

 

The pendulum is a horizontal pendulum compared to the classic vertical one (but not sure of this name because I did not find anything with horizontal pendulum). And the energy of the clock is given from a weight (battery box) which is fixed to an arm which can rotate from the up to the down (you can see the center of rotation with the 40t in the back and the two 5x7 frame) and gives energy to the anchor escapement. When it is down, a motor automatically lift it to the upper position.

So, how do you call this kind of clock ?

 

Edited by nico71

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Balanced clock would be a good name but I can not find many original clock which that name (maybe it is not widespread in clock making).

Any other proposition ? Especially for the weight system ? 

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New creation ! 

Balance Clock With Remontoire

A lego Technic Balance Clock with Korfhage differential powered remontoire, with building instructions.

Lego-Technic-Balance-Clock-1

Context

After building many clocks, I wanted to make a simple, reliable and with big autonomy clock, that is why I built the Galileo Clock. But after some years, I wanted to build a new clock, not simple and with a big autonomy, but with an interesting escapement and weight system. After some researches, and building many prototypes, here is the final result.

Lego-Technic-Balance-Clock-2

How does it work

I wanted from beginning to not use regular pendulum in order to display easily on a desk. I started study the flying pendulum clock but it was to hard to have a correct time keeping with only Lego (maybe for a next clock). Therefore I moved to a classic balance arm on a knife edge suspension (same as on my Galileo clock) with anchor escapement. As I wanted to keep simple the set up of the clock, I only made one setting per pallet, which is simpler than my Galileo clock but less efficient (and took many time to develop).

Lego-Technic-Balance-Clock-5

The other interesting system is weight system. I wanted first to use pullback motor, but despite the fact I have found a way to wind it without stopping the clock, the provided torque was so inconstant that the clock did not work properly. That is why I wanted after to use the battery box as the weight, I have put it on a rotary arm as the clock has to run on a desk (not room underneath). After some researches, I came to the differential idea to make the remontoire which has been patented by Edward Korfhage in 1952. You can see the principle in this gif :

korfhage-differential

Therefore, the weight (which is the battery box) is attached to the cage of the differential and give the main movement. Then, a planetary is connected to the clock drivetrain and the other planetary to the remontoire drivetrain. As the drivetrain is connected to the M-Motor with a worm gear, it is standstill. Therefore the torque is given to the clock when the weight fall.

Lego-Technic-Balance-Clock-11

The remontoire is operated by a switch mounted on the battery box. A lever is connected to the switch, and when the battery box falls, the lever gets in contact with a white end stop which activates the switch. The motor is then powered and the differential rotated in order to lift the battery box. The stop of this movement is made by an other white end stop which put the switch to its neutral position.

Performance

Talking with performance, there are good, but not very good.  The remontoire is operated every 5 minutes which may seem low but the angular displacement of the weight is also low comparing to a classic weight and drum system (with meters of rope).  I have used the highest gear ratio I can for having the maximum autonomy and enough torque to operate the escapement. The ratio between the escapement wheel and the minute hand is 5:1 x 5:1 x 5:1 x 3:1 = 375:1. The escapement wheel has 8 teeth, and the tic-tac duration is 1.2sec, therefore for each second which passes, the minute hand moves about : 1 / ( 375 * 8 teeth * 1.2 sec) = 1 : 3600 which is correct. The two wheels on the extremities on the balance arm can be moved to find the correct time of tic-tac. Of course the ratio between minute hand and hours hand is 1:12 made with 12:24 x 12:24 x 8:24 = 12:1 

Lego-Technic-Balance-Clock-8

As I mentioned before, the pallet of the escapement has only one setting by pallet which is easy to setting, but of course not so efficient as a Galileo Escapement. Combining with the fact that the clock tends to speed up a little when the remontoire is powered, give a global accuracy in time keeping of about  1-5 minutes / 24h. I think the clock will run out battery before having many minutes of difference in some day.

Pictures and video

 
See the article on my blog to find more pictures.
 

Building Instructions

Balance-clock-preview-instructions-1

I know that people like building instructions, and I know they like even more for the clock as there are not lot of them, that is why I have created building instructions ! The building instructions are composed of 228 pages, step by step computer rendering pages which look like official Lego one, at the price of 7.5€. The instructions also provided the standard setting dimensions for the escapement and you will find a video at the end of the article to know how to set up your clock. Here is the complete bill of material in picture file :

Balance-clock-preview-instructions-10Balance-clock-preview-instructions-11

But you can also checked it on rebrickable and export in whatever format you want :

rebrickable_logo.png Want to know if you can build the Balance Clock ? The Balance clock has been indexed to rebrickable, check it !

You can see examples of the instructions on my blog.

FI hope you like, fell free to comment, ask questions :)

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On 12/8/2019 at 4:12 AM, NicoChato9 said:

Vraiment beau Nico, j'adore!

Merci à toi !

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New creation ! 

-------------------------------------------------------------------------------------------

A Lego Technic Forwarder based on the inventory of the 42080 harvester, featured articulated steering with steerable rear axle, pneumatic arms with motorised compressor, manual grabber, rotating cabin and opening doors and hood, with building instructions.

lego-technic-42080-model-c-forwarder-1.j

Context

After releasing my 42080 Model D, and after its great success, I wanted to create something different, that is why I have created the Citroen Mehari and Balance Clock. After that, I wanted to create a new model C, because of the challenge. I have searched a set which was recent and had not so many model C, and find the #42080 – Forest Harvester which was perfect : It has an interesting inventory despite the colourful design, and great possibilities with the tires and new pneumatic parts (plus zero model C at this time). I have searched many days for original ideas with this colour scheme and functions and had trouble to find other idea than forest machines, but when I saw the official Log Loader model B of the 42080, it was an evidence : I wanted to create a better forwarder with better design and functions. Here is the result.

lego-technic-42080-model-c-forwarder-4.j

Functions

The model is packed with many functions. First are the suspensions. Each axle has longitudinal pendular suspensions, plus an articulated roll center suspension. It enables to have certain capabilities on rough surface, even if the center articulation tends to make the rear section unstable (because no end stop).

lego-technic-42080-model-c-forwarder-9.j

The second function is the articulated steering. It is composed of an articulated steering operated by the hand of god in the centre (which is not really easily reachable).  It also operates the rear axle which is mounted on a small turntable thanks to a linkage mechanism connected to a connecting rod and lever to the hand of god. The combination of rotating the hand of god and moving the main articulation make the connecting rod move and steer the rear axle. You can see this mechanism underneath and how it works on the video.

lego-technic-42080-model-c-forwarder-16.

The next functions are pneumatic functions. First the model is equipped with motorised compressor, with the battery box located underneath the cabin and the compressor inside the engine bay under the hood. The main hose comes to the two switches on the rear side, each operates one cylinder. The first cylinder operated the main arm elevation, and the second the second section of the arm. On the first cylinder, you can note the base of the pneumatic cylinder is attached to the chassis and not mounted on the turntable. It enables me to make a compact building despite the length of the cylinder and as it is located in the center of the turntable, it can rotate. Therefore, this is the pneumatic rod which rotates inside the cylinder when operating the turntable. Lastly, the second part of the arm is equipped with a linkage mechanism which gives a high range of angular movement, enabling to have a good working area (not like the official B model and its simple arm).

lego-technic-42080-model-c-forwarder-8.j

On the extremity of the arm, there is a manually operated grabber, thanks to a knob knob mechanism on a friction pin, and equipped with rubber claws. As I had not enough gearing with standard Lego unit building (like 16t/16t), I have used two 20 teeth gears with a half stud assembly for the grabber. To finish, you can note that the cabin can be rotated in order that the operator is in front of the working area. It makes the cabin easy removable because only attached to a pin but add a nice value. 

Design

The model is packed with nice details, such as the cabin interior, opening doors and hood, lights, and some displayed tools. But the interesting part was the compromise on the design. The model was based on a John Deere Forwarder for the main proportion and colour. but use the part of only one Lego set. The main problem was the lack of parts in only one colour, like the green or the white. The white for instance determined the way the arm was built and its length. The green for instance determined the possibilities of building for the chassis, hood and cabin. The idea was to build and place the colour in order the model looks green even if it is not totally green. Of course the fact there are two green (regular and lime) is a big limitation. 

lego-technic-42080-model-c-forwarder-10.

Even with that, I am very satisfied of the design and the functions. This is a recognisable forest machine, with non-bulky and colourful design and nice functions. The steering is not very easy reachable and the cabin can be removed easily, but the model is really playable and built only with one single official set which makes the building interesting. The model can be also enhanced by replacing the lime green by regular green, change black parts on the arm by white one,  and add a turntable underneath the cabin to secure it.

Pictures and Video

More picture at https://www.nico71.fr/42080-model-c-forwarder/

Building Instructions

42080_model_D_instructions_preview_1.jpg

Making a model C without building instructions is a non-sense for me. So I have made building instructions ! This is a 187 pages step by step PDF instructions generated by computer, including the list of parts at each step in Lego style instructions. Regarding the quality, I have enhanced again, with a new presentation and background, white edge on black parts, and better pneumatic hose representation and placement. You can see the list of parts in pictures from the instructions : 

42080_model_D_instructions_preview_10 42080_model_D_instructions_preview_11 42080_model_D_instructions_preview_12

But you can also checked it on Rebrickable and export in whatever format you want :

rebrickable_logo.png Want to know if you can build the 42080 Model C Forwarder ? The 42080 Model C has been indexed to rebrickable, check it !

You can buy the instructions for 10€ on my blog : https://www.nico71.fr/42080-model-c-forwarder/

42080_model_D_instructions_preview_1 42080_model_D_instructions_preview_2 42080_model_D_instructions_preview_3 42080_model_D_instructions_preview_4 42080_model_D_instructions_preview_5  42080_model_D_instructions_preview_7
 
42080_model_D_instructions_preview_8 42080_model_D_instructions_preview_9
 
(I have put the image in the post in low resolution for people seen this post on email).
 
Do you like it ? Do you have any questions ? Fell free to comment :)
Edited by nico71

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Could you recommend good tutorials for instructions?, I appreciate the difficulty of making C models but I limit myself enough being a purist :laugh: .

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I advise followwing the tutorial for Lcad (3D model) and Lpub3D 

http://www.melkert.net/LDCad

https://sites.google.com/view/workingwithlpub3d/

Then If you have problem on lpub (maybe you will have), you can ask questions (and read before) topics on ldraw communities https://forums.ldraw.org/forum-22.html

It is some hours to take to have a skill but it worth it ! I try to enhance the quality of my instructions each time and re-use previous content to increase the quality.

 

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Thanks, I already have done this but I suppose that I am the problem not the tutorials, one of my worst issues plus the englis is when I do not have the piece yet in the program it is too much for me... thank you again.

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On 12/21/2019 at 4:41 PM, letsbuild54 said:

LEGO just tweeted out your Christmas Santa Sleigh. Great work as always. 

https://mobile.twitter.com/LEGO_Group/status/1208402109634363393

I have seen this on facebook too, I give them my permission :)

 

On 12/22/2019 at 8:49 PM, Metagross555 said:

That forwarder is a great redesign, but that color scheme chosen by lego is putrid.

Thanks ! In deed, it was not easy to deals with the dual green color ! I think it is easy to make an enhanced version in all green (chassis, cabin and hood) and all white arm to have a neater look !

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After month of works, here is my new creations, you can read the full story below.

Kumihimo Braiding Machine

An automated Lego braiding machine, based on traditional Japanese 7 reels Kumihimo braiding to create a braid, with building instructions.

lego-technic-kumihimo-braiding-machine-1

 

Context

After discover the traditional Japanese Kumihimo braiding, I wanted to create an automated braiding machine to do it. The basic principle is that you have a disc with many reel holders, and by moving the reel, you create a braid. There are many possible variations about the number of reels and movements that you can do but I have chosen one of the simplest : 7 reels for 8 holder space. The idea is that you have always an empty space, and you move the third reel counter-clockwise to this position, then you rotate the disc to the new empty space and you repeat the sequence.

lego-technic-kumihimo-braiding-machine-3

Functions

Instead of making rotate the whole disc, I have decided to have a fixed disc but with a rotating ring with the hook. The principle of having a hook to catch the reel has been inspired by this video which is an electronic programmed Kumihimo machine made with Meccano. I wanted to add some improvements, for instance, a main winder, a system to control the unwinding of the reel and of course make it mechanically programmed by creating a mechanical “brain”.

lego-technic-kumihimo-braiding-machine-10

The “brain” of the machine is composed of two tracks with pins on it and output gearboxes powered by a L Motor. Each track operates a gearbox, and each pin on each track enables to control the way of rotation of the functions. This idea has been taken from my previous mechanical loom. I used the new gear shifter, combining with the knob wheel which enabled to create 1/4 turn to control easily the functions, in run / standby / back. You can see the whole mechanism below :

kumihimo-drivetrain.jpg

The first gearbox operates the hook, by moving a rack which is mounted on a small turntable to enable the rotation of the main ring. The hook can be lifted or lowered independently of the position of the main ring.  The hook assembly is built with two diagonal ramps to allow a combination of horizontal and vertical displacements of the hook when the whole assembly is moved. It enables to catch the reel in the centre, and then lift and go away to prevent jamming with the other reels.  A clutch in the drive train enables to come against the end stops and force a little to be sure to be in position.

lego-technic-kumihimo-braiding-machine-8

The second gearbox is connected to a rotating lever which makes oscillate a fork to make rotate the main ring. The whole assembly of the fork is connected to this ring, enables the positioning around the circle to catch and release the different reels. This part was the most difficult to create, because it had to be very precise in order to move the main ring on the correct position. I have tested many solutions with motor and servo motor, and/or switch and movable end-stop. But each time the result was not enough precise or reliable which make jamming the machine after some time.

The trick I used is rather simple : I have synchronised the speed of the actuator with the brain’s tracks. In order that during the displacement of 2 links of the tracks, the lever of the oscillating fork make 2 turns.

lego-technic-kumihimo-braiding-machine-7

This trick was a good start but not enough to have a reliable and repeating position for the long time. In fact due to the play in the gearing and the shifting mechanism (because it is Lego), the shifting moment when the function is operated is not exactly the same each time. That, combining with the fact that the main ring always rotates in the same direction, make the main ring tends to have an increasing rotation shift. I have figure out this problem with the same trick used in many other machine with cancelling the play by going in the opposite direction each time the assembly go in one direction. That is why, you can see on the video that the main ring rotates, stops, and goes backward a little, this is for cancelling the play to have a reliable and precise functioning.

Last device is the black ring which encircles the reels, as shown in the video, this device has been designed to push down the reels when they unwind naturally because of the main winder. It enables to have a reliable functioning until the reel are empty.

Performance

Even if the machine is big and fully automated, the global speed of braiding is not very fast ! It is explained by the Kumihimo principle which is to move each reel after each other which makes a real rope but takes more time than a classic rope maker. But also because the movements of the machine are rather slow, especially rotating the ring. I have tried to increase the speed but the inertia of the main ring make it rotate too much, that is also why you can see a small friction wheel on the ring.

lego-technic-kumihimo-braiding-machine-16

The Lego solutions I have chosen are also an answer to the slow speed. As I use gearboxes and tracks, I have to have some time between two movements because of the building with pins and knobs, by passing to a neutral position (I can’t go back and forth without passing through neutral). This point, combining with the back movement to cancel the play make the rotation of the ring the critical slowest movement of the machine. That is why I have reworked many time the tracks-pin-layout to make it running faster by combining the movements when it is possible (start rotating when the hook is lifted, etc.). But I will also test with the new Control+ hub and servo motor in direct drive functions when I have, in order to test the maximum speed with programmable servo motor.

The result is a real braid that the tightness can be adjusted by replacing the gear ratio in the main winder.

Pictures and Video

 

Building Instructions

kumihimo_150_DPI_page_1

As usual, I have made building instructions, but I had no idea how long and difficult it will be, because of the rendering of the flexible parts and the many sub assembly. Therefore I present you the biggest instructions I have ever done, with 487 pages ! This instructions reach the standard of quality of pro-instructions with detailed step by step assembly with list of parts and important note during the building (you can check the sample below).  I have also made a “how to set up” video for the machine (see at the end of the article).

You can see the list of parts in pictures from the instructions : 

kumihimo_150_DPI_page_485kumihimo_150_DPI_page_486kumihimo_150_DPI_page_487

But you can also checked it on Rebrickable and export in whatever format you want :

rebrickable_logo.png Want to know if you can build the Kumihimo Braiding Machine ? The model has been indexed to rebrickable, check it !

You can buy the instructions on my blog for 10€ of on rebrickable.

sample of the instructions (more sample on my website)

kumihimo_sample_instructions_SD.jpg

Video of the set up of the machine on my website https://www.nico71.fr/kumihimo-braiding-machine/

I hope you like ! This creations required months of work, with serious headache, I am happy to publish it and go back to a more "wheely" creations ! Fell free to comment :)

 

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Wow, this is absolutely amazing, congratulations!  I LOVE this kind of machine.  Not really that interested in "wheely" creations :laugh:

I am not sure I understand how you keep the blue "oscillating fork" in sync over the long term.  Even if each movement gets reversed, if it is controlled just by timing via the orange clutch parts, won't the errors build up over time?  Are the errors just small enough that in practice you can run it for hours without needing to recalibrate?  Or do you have some way of keeping it in sync that I am not seeing?

Edited by aeh5040

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