[WIP] Pagani Huayra

[Jeroen Ottens]

Hi,

As mentioned already in the topic of @langko's fantastic version of the Pagani Huayra, I will be building a 1:8 version as well. I still owe you all the final photos of the Ford and Valkyrie and in the meantime there is another car that needs to be finished, but I am very excited to build this one, so I couldn't help myself starting already.

The design started with thinking about the gearshift module. In the real car the gearshift is used both for D-N-R switching and for up-down switching. I've made a couple of iterations and thought it might be interesting to show them:

The iterations go clockwise, starting from the bottom left. The whole idea is that moving the gearstick left to right controls the D-N-R switch. In the right most position the shift can move forward/backward to shift up/down. So three things are needed:
1) A way to get two signals to the back (D-N-R and up-down)
2) A way to get those two signals out of one stick
3) A way to block the movement of the stick when in N or R

I started with rebuilding the stepper mechanism of the Porsche, that was perfected later by @Didumos69, as I hadn't used such a mechanism for a while, but I think this mechanism is easier to combine with a stick shifter than the Sian one, which works better for paddles.
Then I thought it would be a good idea to use a small turntable to attach the gearstick to as that would make a very easy separation between the two movements of the stick, using a 9L link with balljoints (upper left version). However, this meant that the stepper mechanism gets quite close to the back of the chairs as the link is only 9 studs long. So I experimented a bit with the placement of the stepper mechanism (sideways, vertical, small width config), but none of them gave me the feeling that there would be enough space for the seats.

Then I got a jolt of inspiration when I looked more closely to the real mechanism. I couldn't get a truly good picture, but the idea I got was that the back and forth movement should be somehow decoupled from the sideways movement, so that I wouldn't need the 9L link, but could use a regular beam instead. I started with two togglejoints, but that quickly evolved to the construction at the bottomright. Here a CV-joint is used to decouple the two rotations (if that description makes any sense still).

I then added a structure on top to guide the gearstick, such that it only can go back and forth when it is all the way to the right. Proportion wise it is a bit too wide at 5 studs, but for a LEGO mechanism I don't think it can be made much smaller, so I am happy for now. I even managed to add the handbrake. For now that is decorational only.

Quaestion, critique and comments are welcome as usual. I'll try to give updates a bit more regular as this car is so full of details there is always something interesting going on, whatever is developed.

[suffocation]

Took me a while - not the sharpest pencil in the box - but I think I finally figured out how the mechanism works. That's an ingenious solution you've come up with!

Looking forward to seeing more - your builds are always full of cool, ground-breaking ideas.

Edited May 25, 2022 by suffocation

[Alex Ilea]

Looking promising, waiting for those promised photos 

[Zerobricks]

Brilliant idea with the shifter!

[SNIPE]

If it also has a flappy paddle shifter (like the real car), I recon the new 1x2 curved technic panels from set 42141 will work with the knob wheels. I've made soo many versions but it either does not shift, shifts but then backshifts, or it shifts but its not strong/reliable enough and it only worked if I used two hands on the paddles else it jams 'foward'. In any case that still does not replace the stepper mechanism which I belive those parts could well do. I used a #2 connector and two 2L  beams tied together by rubber bands.

Hopefully someone might crack it soon, in the meantime ill keep trying. I actually needed a small paddle shift mechanism for my ultimate 42142 MOD.

Regards, Snipe

Edited May 25, 2022 by SNIPE

[Thirdwigg]

Very cool designs, and it's neat to see all the iterations in one photo. Hopefully the rest of the car can have more of these creative little nuggets of technical mastery.

[Jeroen Ottens]

Thanks for all the comments.
@SNIPE: Success with the flappy pedal shifter, my version won't have this, plus I don't have these new comma parts.

Here is the next design iteration photo:

This is the rear suspension. I am planning to use the new hard shocks of the BMW/Ferrari Daytona as I would like to stick to one spring per wheel and these springs have only one stud travel.

I started with a version where I tried to replicate the A-frames on both the upper and lower wishbones. LEGO really doesn't have proper A-frames, which makes the suspension setup quite wobbly (forcing you to use friction pins to minimize the play in the suspension). However, as the horizontal part of the wishbone is rather long (7 studs), while the vertical part (where the spring is connected to) is only 2 studs, the vertical travel of the wheel is ~3.5 studs, which of course is way too much for this car. I also don't like the cluttered look of all these horizontally mounted ellipses.
So in the next iteration I dropped those, moved the inner wishbone rotationpoint further outwards, so that the wishbone is only 3 studs, whereas the vertical (or slanted) part is ~4.5 studs. This would give a less than 1 stud travel if the spring was mounted vertically, but as the spring is mounted at an angle the travel is actually much more. Also, because the spring is 9 studs long and it needs to give some space for the drive axle below it, it has to be mounted more horizontal than vertical. And then it still has to fit in the width of the car with a differential squeezed in as well.
Long story short, the last iteration does meet most requirements I think. The wishbone is 3 studs, as is the vertical part. The differential is pushed very low, but there will still be some space below it to fit a flat panel. I may still add some diagonal parts, but that will be more for looks than structural integrity.

[Jonfensu]

That gearshift module is brilliant!. I like how the result is a compact and clean lever system at the bottom, in comparison to the version that uses the 9L link.

I am building a Manual 6 speed gearbox, with a remote gearshift and this suits me perfectly and clearly in that case it brings many advantages over the regular method that uses a 9L Link. For example the force will be constant on every gear and you will not have the bottom ball joint sticking out to the sides when you move the stick sideways

Thank you for sharing it!

[Jeroen Ottens]

The next phase is to make a chassis that is stiff and has room for a gearbox. Here are a couple of the iterations:

I started with mounting the suspension assemblies to a crude frame (upper left). I also added the gearstick to get an idea of where the cockpit is located. One of the challenges of this model will be the stiffness of the chassis. As the car doesn't have a central column the longitudinal stiffness has to come from the two tubes at the sides. In my first iteration I used 3x11 panels with 10 holes to form a tube with a 3x4 stud cross section. But once it was completed I feared that that didn't provide enough stiffness for such a big model. So I built a new tube with a 5x4 stud cross section. But to be honest I think these are a bit too high or wide (depending on the orientation), so I might revert back to the 3x4 tube, but then positioned with the 4 stud side upwards.

The next thing to do was to position the engine. As this model uses the LEGO cilinders the whole engine is disproportionally long, so I wanted to push it as close to the cockpit as possible. Even so, there is very little room left to the rear suspension. The height is determined by the stepper mechanism below. That does give some good space for the gearbox. I also added the 7x11 frames (upper right) to get some more stiffness in the chassis. Putting these in early gives some good guidance how the gearbox should be fit in.

I started with a nomal, longitudinal oriented gearbox (middle), but I quickly ran into all kind of space issues. Especially the connection to the transversal placed D-N-R switch proved difficult in the small space. So I changed the orientation of the gearbox to a transversal one. Then it was a bit of a dance between the 7x11 frames, the gearbox subassy's and the connection between the two, but in the end I got something that at least theoretically works (lower right). The bracing is non-existent at the moment and I also still have to check whether all gear ratios are correct. There is also still quite some space below the engine, so I might be tempted to add a blocking mechanism to convert this to a 7 speed gearbox.

 

Edited May 29, 2022 by Jeroen Ottens

[astyanax]

Love the peek into the kitchen! Many thanks for taking the effort to write this up! 

[LvdH]

Looks great and also nice to see some different iterations. The transverse gearbox is definitely cool. Any idea on the color? I’m guessing red, using many of the new parts in the Ferrari? Those new shocks are also perfect for this car, but I can tell you’re already planning on using those. 

[Erik Leppen]

Getting stiffness in a flat chassis will be a challenge. Especially if you're not going through the center. Studless builds are very prone to torsion, so that will be hard. Have you considered creating a box using those new 19x3 frames? I could imagine those could help a bit. Also, have you considered studded bricks? It's rather easy to get longitudinal stiffness just by using brick-plate-plate-brick over the entire length. Such a beam would really get in the way of everything else, but I wanted to mention it anyway, because I used this technique once or twice.

[Alex Ilea]

Looking good so far. I would suggest you double the tickness of the floor or at least add some support beams  very colse to the seats. It might help with the stiffness.

[Jeroen Ottens]

On 5/29/2022 at 12:25 PM, astyanax said:

Love the peek into the kitchen! Many thanks for taking the effort to write this up! 

You're welcome. Nice to hear it is appreciated

On 5/29/2022 at 2:00 PM, LvdH said:

Looks great and also nice to see some different iterations. The transverse gearbox is definitely cool. Any idea on the color? I’m guessing red, using many of the new parts in the Ferrari? Those new shocks are also perfect for this car, but I can tell you’re already planning on using those. 

The colour will not be red, even though that would have been a much easier colour...

15 hours ago, Erik Leppen said:

Getting stiffness in a flat chassis will be a challenge. Especially if you're not going through the center. Studless builds are very prone to torsion, so that will be hard. Have you considered creating a box using those new 19x3 frames? I could imagine those could help a bit. Also, have you considered studded bricks? It's rather easy to get longitudinal stiffness just by using brick-plate-plate-brick over the entire length. Such a beam would really get in the way of everything else, but I wanted to mention it anyway, because I used this technique once or twice.

 

6 hours ago, IA creations said:

Looking good so far. I would suggest you double the tickness of the floor or at least add some support beams  very colse to the seats. It might help with the stiffness.

Thanks for thinking along. I am hoping that using thick torsion tubes at the side of the chassis will help both bending stiffness and torsion stiffness when I can connect them form-locked to the rest of the chassis. I still don't have any 3x19 frames due to the clusterfuck that LEGO made of the B&P ordering, so for the moment I'll refrain from using them. I know that studded beams do offer superior stiffness over studless beams, but I don't like the complications you get when integrating them with the rest of the studless structure.

 

 

 

 

[Jeroen Ottens]

Oops... I intended to add a progress report as well, but I totally forgot.

Here is the latest stage of the design. I spent most time on digitizing the progress so far (including stepping to ensure that it is actually buildable). But I also did a bit of real-life building to work on the distinctive framework around the engine:

I am not sure whether the dimensions fit inside the overall shape (I think they do), so there might be some redesigns necessary later in the process.

The disadvantage of the position of the gearbox is that it completely blocks any longitudinal axles running from the front to the back at the floor level. This will complicate the aeroflap mechanism a bit and, most importantly, introduce some play in that mechanism. So that will be something to keep an eye on. It also means that it will be nigh impossible to implement working fans in the front like @langko's version.

The engine currently sits a bit high, I already found a way to lower it by half a stud. This will give more room for the detailing.

[langko]

I've enjoyed seeing the WIP so far, I think even more so as I can compare the differences in building style to my own version. Its always cool to see how different 2 people approach the same model! The shifter design is very clever and unique, as well as the transverse gearbox. I had played around with a transverse gearbox in mine to, but only briefly as I ditched it due to the problems you've mentioned with routing axles. It'll be interesting to see how you approach the flaps with such a design! I like the idea with the new shocks, I think they are perfect for cars with these type of suspension setups compared to your more traditional layout. Only thing I'm not sure is the colour... Those shocks only come in blue or red at the moment and I personally think both would look a bit out of place with the yellow wishbones. There are some Huayra's with a more neutral theme (see below). Not suggesting you go all black, but I think some combination of LBG, DBG, Black and Metallic Silver along with the new shocks could look quite cool. 

Details in the engine bay look cool so far! The LBG 'X' shape is really well done. The detail between the suspension is really accurate as well, I had something similar in mine but I had to get rid of it in the end because it was clashing with the clamshell... May I ask what the reference material is for the black flex axle in the rear above the "X"? I noticed you did the same thing is your 10:1 model, but I'm yet to see a photo of a Huayra or another MOC for that matter that has that detail. (See above photo)

Anyway, great progress so far, if you keep up at this rate you'll finish is less than half the time I spent on mine haha. Good luck with the next steps. Looking forward to see what colour you end up choosing for the bodywork too.

[Jeroen Ottens]

On 6/6/2022 at 1:47 PM, langko said:

I've enjoyed seeing the WIP so far, I think even more so as I can compare the differences in building style to my own version. Its always cool to see how different 2 people approach the same model! The shifter design is very clever and unique, as well as the transverse gearbox. I had played around with a transverse gearbox in mine to, but only briefly as I ditched it due to the problems you've mentioned with routing axles. It'll be interesting to see how you approach the flaps with such a design! I like the idea with the new shocks, I think they are perfect for cars with these type of suspension setups compared to your more traditional layout. Only thing I'm not sure is the colour... Those shocks only come in blue or red at the moment and I personally think both would look a bit out of place with the yellow wishbones. There are some Huayra's with a more neutral theme (see below). Not suggesting you go all black, but I think some combination of LBG, DBG, Black and Metallic Silver along with the new shocks could look quite cool. 

 

Details in the engine bay look cool so far! The LBG 'X' shape is really well done. The detail between the suspension is really accurate as well, I had something similar in mine but I had to get rid of it in the end because it was clashing with the clamshell... May I ask what the reference material is for the black flex axle in the rear above the "X"? I noticed you did the same thing is your 10:1 model, but I'm yet to see a photo of a Huayra or another MOC for that matter that has that detail. (See above photo)

Anyway, great progress so far, if you keep up at this rate you'll finish is less than half the time I spent on mine haha. Good luck with the next steps. Looking forward to see what colour you end up choosing for the bodywork too.

@langkoThanks for the feedback & comments. I have found a way to route two axles from front to back, but ideally it should be three, to also get the spinning fans in the front (I really like that feature on your version), so still some work to do :).

For now I will keep the yellow wishbones with the red shocks. I just got my copy of the Daytona, so I can see how the physics work with these stiff springs.
The flex axle at the bottom of the X is based on this photo:

There is an extra window above the X. I always assumed that that window is not fixed to the clamshell, but maybe I am mistaken here. I'll see if I can find a good picture of the opened clamshell.

And time for an update as well:

First of all I rebuild the model from the ground up based on the digitized version. Just to see whether all the steps are possible and whether the tweaks added to the digital design also work in real life. Then I started working on the front axle. Front axles are always a pain to design because the LEGO wheels are too wide (especially in the front), thereby limiting the space for the steering axle. The rotation points of the wishbones need proper bracing, which quickly results in bulky frames connecting them. The connection from the tubes on the outside of the chassis to the frame around the axle is difficult to make. And in this case I also wanted to add a driveheight adjustment mechanism and a mechanism to transfer the steering input to the two aeroflap axles.

Here is a photo of three of the iterations:

On the left is an early version. The steering rack is at the front (teeth upward) and a second steering rack (teeth upward) is behind the axle. That second steeringrack drives two 12T gears on the two aeroflap axles. Because the second rack is on the opposite side of the axle it has to move in the opposite way as well to avoid colliding with the wheels. I put two 16T gears inside to revert the rotation. Of course this does give a slight misalignment of 360/16/2 = 11.25 degrees. Small enough given all the play in the LEGO, but still annoying.
The ride height adjustment mechanism consists of a small crank (the yellow crank from a fake engine) that can rotate 180 degrees. The lower mounting point of the spring is attached to that crank. Rotating the crank will move the attachment point 1 stud closer to the outside, which results in a 1 stud higher rideheight. With these big springs, plus the movement they have due to the rideheight adjustment there is not much room to route the steeringaxle back to the cockpit. To brace the mounting points of the upper wishbones I had to add this black 15L beam on top, which sort of ruins the look of the whole setup.

So on to iteration two in the middle. First of all I realized that I could reverse the direction of the two gearracks by mounting one of them upside down. This way no 16T-16T gearing is needed in between them. I also use some angles 3-7 beams to strengthen the upper mounting points. This gave a much cleaner and tidier frame already. But the gearing for the drive height adjustment system all comes in front of the axle, which leaves then no space for the fans.

Which brings me to the final iteration on the right. Here the gearing for the drive height adjustment is behind the axle, while the aeroflap gearrack is now in front. It took me a while to realize that I actually don't need a gearrack anymore, as the movement of the aero gearrack now has the same direction as the steering gearrack as they are on the same side of the axle (for the eagle eyed that still spot a 13L gearrack: that one is only used because of the perpendicular axleholes it provides). The bracing is minimized and there is enough room for the fans in front. But because of the limited space behind the axle the ride height adjustment will be operated with a lever instead of a knob.

Comments, questions and critique are welcome as always

 

[Alex Ilea]

This is gonna be a crazy good model! It kinda motivates me to work on my own stuff as I am building a 1:8 car right now.

[langko]

13 hours ago, Jeroen Ottens said:

Thanks for the feedback & comments. I have found a way to route two axles from front to back, but ideally it should be three, to also get the spinning fans in the front (I really like that feature on your version), so still some work to do :).

Glad to hear! Good luck with the fans, I'd like to see that in your version as well.

13 hours ago, Jeroen Ottens said:

There is an extra window above the X. I always assumed that that window is not fixed to the clamshell, but maybe I am mistaken here. I'll see if I can find a good picture of the opened clamshell.

I had always assumed that the window was fixed to the clamshell, mainly because I'd never seen it sitting above the 'X' is photos of the engine bay. (like photo I posted above). I did some research and here's a photo that shows it well.

13 hours ago, Jeroen Ottens said:

Which brings me to the final iteration on the right. Here the gearing for the drive height adjustment is behind the axle, while the aeroflap gearrack is now in front.

This is pretty much what I ended up with too haha. Here's my layout if your interested (without all the bracing and everything else). This is with the suspension in the lower position. The yellow axles with the 24 tooth gears rotate 90 degrees changing the position where the springs are mounted at the bottom. In the higher position the bottom of the springs are a stud above the yellow axles instead of a stud to the side. There is proper bracing to support the 2x1 liftarm (60483) when it is in both positions to take the stresses off the yellow axle. With the steering rack the horizontal grey 11L axle is fixed in place allowing the gear rack to slide left/right along it. Again, there is more bracing everywhere but this is just to explain the mechanics. It's all quite dense but works well.

 

[Jeroen Ottens]

It has been a while since the last update, but I finally found time to work on this project again.

I am still iterating on the front suspension setup. I lost count of how many versions I have built, but it must be dozens by now. My idea of using a linkage mechanism to control the height adjustment will not work as it takes half a rotation of the axle instead of a quarter turn which I somehow thought it was. So more iterations to follow . I'll let that lie for a while to get some new inspiration.

So I moved to the back instead. I had some idea to use transpurple minifig heads for the exhaust pipe system. Here you can see them sitting in the back, just behind the rear grille. What do you think of it?

I also started working on the bodywork.

 

I am reasonably happy with the current status. The central section has a good flow I think. Also the new triangular panels in black are just made for this. The only thing is they are a bit too curved and the transition to the front end of the clamshell will be tricky.

 

The rear grille hangs on a single pin per side, so some bracing will need to be added to fix the angles and add sturdiness. There is stupendeously little space though, plus the aeroflap mechanism also needs to be fitted in. And ideally also some meshing will be added to the big ellips gaps. Which will take again a lot of space to fix I'm afraid as nothing is straight in this section. So more nice challenges to work on .

Comments, questions and critique are welcome as usual.

Edited August 6, 2022 by Jeroen Ottens
added bodywork photo

[Scoar Sonander]

Really great as always, I would never have thought to use minifig heads for exhaust pipes. 

[Supercar Enthusiast]

any more updates?

[Alex Ilea]

On 12/11/2022 at 9:53 AM, Supercar Enthusiast said:

any more updates?

I am also interested in this!

[Jeroen Ottens]

Sorry for not posting anything sooner. This build has not been progressing as fast as I had hoped. Before going into that here is a photo of the current state of affairs:

It is not very clear from the photo, but most of the yellow you see is actually bright light orange (basically all, except for the chairs, the flexaxles and the instrument panel). It is one of the cleanest interiors I ever designed I think.

The reason for the long delay in the update has been the gearbox. I started the design with a transversal mounted gearbox (like I had in my 1:10 version as well), but when I tested it in real life the friction was just prohibitive and it was cracking gears in half of the gears.

This set me back big time as I had designed the chassis around the gearbox. So I started the whole process again, but now with a more regular oriented gearbox. However, since the D/N/R switcher is controlled by the gearshift stick I needed to place that part in transversal orientation. Which was a pain the a**, as the engine is longitudinal oriented, so that requiredat least two 90 degree bevel gear connections. The location of that D/N/R switcher was another headache. I first wanted to put it below the engine, but that pushed the whole engine up, which made it interfere with the cross tubing above it. Then I tried to put it behind the engine, but the space there was too tight and blocked even more of the tubing.

In a moment of inspiration I decided to rotate the whole D/N/R switch 90 degrees (to make it longitudinal) and place it between the shocks of the rear suspension just above the diff. This solved all the space issues around the engine (and by rearranging the gears I could even move the engine one stud lower), but as I now had to add a linkage between the driving axle for the D/N/R switch I could no longer use the white axle-connector to keep the switch engaged in D/N/R positions. So I had to make a mechanism to keep the switch locked in three positions (I currently have no photo of this mechanism, I'll post it when I have it).

So I finally thought I was out of the woods with this gearbox, but then I found out that the stepper mechanism doesn't properly engage. It is a variant of the Porsche stepper mechanism, which is a bit more fickly than the Bugatti/Ferrari version. I still have to solve this issue, but once that is done I am pretty far as the bodywork is actually quite far.

All in all, I am quite pleased with the state of the design as it is now. The chassis is incredibly stiff due to the use of two 3x19 frames per side (hidden from view behind the 3x13 curved panels), I am really fond of the interior design and the outer shell is starting to flow as well. The front suspension can be lowered, there are working fans in the front (the eagle eyed reader may have spotted that already) and the aeroflaps are working both in the front and the rear.

Hopefully I'll have some time in the coming weeks to make more photos to show a bit more of the progress.

[langko]

Great looking interior! Definatly agree it’s one of the best you’ve ever done. LEGO needs to take some notes haha, all the interiors on all 4 of there UCS cars look unfinished and low on effort...

Look forward to seeing some more photos. The struggles you’ve had with the model seem well worth it, well done with persevering through the headaches (I know the feeling all to well, I rebuilt the entire chassis multiple times on mine)