Didumos69

The caster angle is a good idea, but there are a few other things that I would design differently: - The track rods (links) are very angled. this makes steering sloppy, especially during turns. I would try to place the tooth rack closer to the axles, see also LPEpower's video (at 2:15): - The shock absorbers are attached to the lower suspension arm, which may cause the lower suspension arm to get disconnected from the wheel hub when riding over a bumpy surface. I would try to find a setup with the lower suspension arm placed up-side-down or I would try to apply the shock absorber to the upper suspension arm, for instance in a push rod style (horizontally placed, see for instance: http://www.sheepo.es...hbone-with.html). Good luck!

Agree. Sometimes it's a pitty that the discussion is about legality rather than applicability of an idea. On the other hand I realize that when I put this kind of ideas out in the open, I should be prepared for any kind of reply. In this case, I think JJ2's first reply has put exactly the right degree of relativity to legality.

A very nice idea, although I can't judge the stability of the whole thing. As far as I can judge the photo's, I also see that the ball joints of the hub are still not positioned on the center plane of the tyre. A custom wheel hub might be inserted into the wheel even deeper and could be combined with kingpin inclination, bringing the whole setup even closer to true center point steering. I wonder if this would fit (it does fit the rim for this size tyre): LDD-file

Then luckily the 'illegal' part of the design is hidden behind the rim, so you might just get away with it ;-)

When you have ever built wheel hubs that use an axle to attach the wheel to - typically a 5.5L axle with end stop - then you must be familiar with the substantial slack such a connection is suffering from. If your wheel hubs have a more or less flat surface facing the wheel, like the wheel hub shown below, then it helps to fill the inside of the rim with 3 2L half beams, each attached to 2 3L axles, which are in turn inserted into the 6 pin holes of the rim. When the half beams are lowered deap enough into the wheel - you have to push them slidely away from the center of the rim to get them into place - and the 3L axles are inserted all the way into the half beams, the whole thing does not only make a tight fit, but also makes a nice flat surface together with the outer end of the axle hole of the rim. See images below. Now when you slide a belt wheel over the 3L axles on the other side of the rim, the whole thing is ready to slide over the axle coming out of the wheel hub. While doing so, make sure the 6 3L axles are not inserted further into the rim, as that would disturb the flat surface on the inside of the wheel. Slide the rim over the axle all the way. Finally, slide two extra half bushes to avoid the rim from sliding off the axle. Now the slack of the rim-axle-connection should be reduced by about 50%, while the rim rotates as smoothly as before. EDIT: I found out that using half bushes on the inside of the wheel makes an even better surface and reduces the chances on stuttering even further (I haven't experienced any stuttering sofar). The edges of the half bushes are slightly more smooth than the edges of the 2L thin liftarms that I used before. To anchor the setup I placed the three 2L liftarms on the outiside of the wheel. To finish the whole thing there are 2 options: Option 1 - For the ones living on the edge: Before sliding the rim onto the 5.5L axle, place a half bush right between the 3 short liftarms. You can't just push it into place; use an auxiliary axle to align the half bush with the rim and make sure the last part you put in place is one of the 6 3L axles. That should do the trick. This makes a tight finish (2nd image below). Option 2 - For the LEGO purists: After sliding the rim onto the 5.5L axle, place a half bush on the axle to lock up the 3 short lift arms. This makes a legal finish (3rd image below).

Moving the engine from front to rear module: The parts needed to connect the engine:

I haven't seen these in this collection yet: Double wishbone suspension with longitudinal torsion bar. From an AWD-platform I'm building. Front module Main characteristics: + Driven axles with differential + 4 stud suspension travel + 5 stud clearance (with 94.8 x 44 R balloon tire) + Progressive camber angle + Caster angle + Kingpin inclination + Ackermann steering + Tweakable torsion tension + Prepared for carrying a V12 engine Rear module Main characteristics: + Driven axles with differential + 4 stud suspension travel + 5 stud clearance (with 94.8 x 44 R balloon tire) + Progressive camber angle + Tweakable torsion tension + Prepared for carrying a V12 engine In action: For LDD-files, see: http://bricksafe.com...ding-directions

Okay, here we go. LDD-files with building directions for the front and rear modules are now online. Please follow the instructions on this page: http://bricksafe.com/pages/Didumos/steppenwolf/building-directions. I also submitted the modules as MOC with parts list on Rebrickable, but I'm still awaiting approval. Cheers!

Yes, I will release the LDD-files, at least for the front and rear modules. However, they still need some rework. As soon as they are ready I will post download directions here. The slack is slightly better than a nomal axle through a single 1 stud hole due to the end-stop on the 5.5L axle. Front suspension and rear suspension both have a positive camber (with an angle )of about 4 degrees) when the suspension is fully expanded. This makes the wheels stand up perfectly straight under the cars own weight, regardless of the present slack. Slack also depends on how tight the wheel is attached to the axle. I use a little trick - although others are convinced that two extra half bushes on the same axle will perform equally well - with a rubber connector, see image links below. My experience is that this works especially well with the 6-pin-hole rims. I'm even afraid to break parts when I try to slide this over the axle by hand. That's why I postponed installing this trick untill the build is completely finished. I'd say you have to try to know if this will be useful. http://bricksafe.com...jpg/800x600.jpg http://bricksafe.com...jpg/800x600.jpg http://bricksafe.com...jpg/800x600.jpg http://bricksafe.com...jpg/800x600.jpg Alternatively you could replace the double cross block that holds the axle with LPEPower's turntable wheel hubs: http://www.lpepower....table-wheel-hub. For a video see: . My guess is that the LT cardan ball will fit in the wheel hubs just like the U-joints do. However, it would bring the wheel one more stud away from the virtual kingpin, which does not improve the steering characteristics.

Here are some cut-outs showing the basic setup of the front and rear suspensions: And finally the wheel hubs. Note the yellow half bush that helps tighten the tilted setup:

I'm planning to share buillding directions in terms of groups in an lxf-file for the front and rear modules. I will have to finish those first though. For the center module probably not because it includes Boratko's 5+R AWD gearbox and he is selling instructions for that gearbox himself. But maybe I could leave the gears out.

I don't know if this suspension setup will fit the smaller scaled 42043. But if you would want to use the tilted wheel hubs shown above than you should know that the position of the pivot points probably requires a tooth rack that is an even number of studs long. In my build I had to place an 8 stud tooth rack between the track rods. It looks like this: Once I have updated my LDD-files with the real life build I will place some images that show the complete suspension setup while leaving the rest of the design out.

Thanks! I said it before, your video's on youtube have been of great help!

And one more short preview video:

Thanks! I just posted a new topic about the build in the image: http://www.eurobricks.com/forum/index.php?showtopic=123304

UPDATE: Thanks to an amazing effort by Thorsten Spelz full-blown building instructions are now available on Rebrickable! UPDATE: I updated building directions to reflect some improvements to the front suspension. See entry #30 of this topic. Hello, I started a topic on my 'Steppenwolf'-project before, but that post feels a little bit like a false start by now. At that stage I only had digital ideas and there where some correct critiques about the designs I showed, especially about the custom wheel hubs. Since than I thoroughly redesigned the front and rear suspension and about a month ago I started building my 'Steppenwolf'-chassis. Now I have come to a point to show the first 'real life' results and I would like to use this topic to show progress and to elaborate further on specific parts of the concept. First of all it was a real sensation to start building with real bricks after 25 years of not 'playing' with lego. To show a little bit of where I come from when it comes to Lego Technic: this is my last build from about 25 years ago: https://bricksafe.co...jpg/800x600.jpg https://bricksafe.co...jpg/800x600.jpg With the 'Steppenwolf'-project I aim for an AWD platform that can serve as the base of a push-along car. It is meant to fit 'ordinary' AWD cars rather than Baya truck-like vehicles. The platform combines all-wheel-drive with Ackermann steering, progressive camber angle, caster angle, kingpin inclination, 4 stud suspension travel and 5 stud clearance (with 94.8 x 44 R balloon tire). As suspension and drive characteristics have the main focus in this design, I prefer not to see these characteristics being affected by a too flexible chassis. I want a rigid chassis that does not twist too much while riding on an uneven surface. All these ideas resulted in a platform that has been built up from three main modules; the front module, the center module and the rear module. These main modules incorporate the complete drive train, including front axles, rear axles and (5+R) gearbox. The gearbox is based on Boratko's 5+R AWD gearbox and has been extended with a center differential lock. The platform has been completed with three secondary modules; a v12 engine, a steering console and finally two car seats that can move and tilt. The engine can be placed at the front or at the back of the chassis. The seats have been inspired by the car seats as can be found in Nathanaël Kuipers' Concept 4x4 and have been extended with the ability to move back and forth. Both front and rear suspension are independent and based on the double wishbone concept with a longitudinal torsion bar attached to the lower wishbone, see the image below. This weekend I have been able to actually combine the various modules of my build and I'm quite happy with the results. Here are some pictures and a short preview video. Ackermann steering: For the front suspension the shock absorber is directly attached to the lower suspension arm which has been placed up-side-down to avoid it from getting detached from the wheel hub: At the bottom of this picture you can see how the outer end of the longitudinal torsion bar has been fixed to the chassis: Once more a front suspension close-up: The rear suspension is also a double wishbone suspension with longitudinal torsion bars. Instead of using cusps and balls it uses normal axles and liftarms. Each wheel hub is stabalized firmly with two stabilizing links: Both front and rear wheel hubs are based on a setup that allows the lower suspension liftarm to be placed upside down while leaving enough space for the U-joint attached to the wheel axle (5.5 with end stop) to support 4 stud suspension travel: 5 stud clearance: More photo's can be found here: https://bricksafe.co...progress-images And finally here is a short preview video showing the suspension: I'm very curious what you all think of this. My next step will be to build the body work and I will report on that in this topic. I also plan to post some extra details on the front and rear modules of this design - if there is any interest. I might even share lxf-files containing construction directions for these modules (sofar I didn't plan to make real building instructions, but when the whole thing is finished and when there is enough interest, I might decide to put in the effort). Thanks so far! Diederik EDIT: Building directions for the complete chassis may now be found here: http://bricksafe.com...ding-directions

This is all I have and all I need sofar...

Very interesting. The nice thing about this suspension type is that it offers a relatively subtle variable camber angle - especially when the beams surpass one another substantially - with less moving parts than for instance double wishbone suspension. Many rigid axle suspension types typically have an extremely varying camber angle which is not very good for road holding. Tatra suspension is another example of such exaggerated camber angle variation. Less rigid suspension types such as McPherson strut suspension and double wishbone suspension usually have a variable camber angle with a virtual rotation point way beyond the center of the car to confine the camber angle variation. Twin beam axles accomplish this with long parallel beams and less moving parts, which is what I like about it. When it comes to building lego suspensions I still prefer the double wishbone setup because it is strong and can be easily adjusted to specific handling characteristics. Thanks for putting in the effort and sharing this with us. Diederik

I re-examined the whole thing. The problem was that not all gears with cluth had enough space to rotate freely. This actually troubled gears 1 to 5 too, but not as much as reverse, Once I made sure all gears could rotate freely, the gearbox perfomed as a I had hoped; perfect in all gears! The only problem that remains is that after shifting gears several times, some of the gears with clutch again get closed in and slowed down by neighbouring gears on the same axle. This is probably because some of the gears I used - especially the grey 12 tooth double bevel gear - tend to slide along their axle quite easily, causing them to gradually move towards the gears with clutch when shifting gears. I replaced them with black ones, which in my case are more tight. Hope that will keep this probelm away.

Thanks! I did see that one, didn't know it was a replacement.

Someone did the Mercedes G63 AMG: http://www.moc-pages.com/moc.php/378114

Okay thanks, I will re-examine or even rebuild the whole thing. I already had a problem with an axle being not straight which screwed the behaviour of the entire gearbox. What is the difference between old style and new style 8 tooth gear?

When applying the images of Zblj I would argue that the wheels closest to the pair of non-steering wheels need more pivot point offset then the more distant pair of wheels. But this is only the theoratical part of course:

Obviously the example you are mentioning does not have steering on the second line of wheels: http://cdn.blessthis...3-amg-6x6-2.jpg If the vehicle will only ride sand then I don't think there's a benefit. If it should be suitable for tarmac as well, then there would be. In that case the practical benefit would be a reduction of wear on all 4 rear tyres and probably better handling.

Hi, In a push-along car that I'm building, I'm using Boratko's 5+R AWD gearbox and I'm running into problems when putting the gearbox into reverse. I have an AWD setup with three differentials, the center differential is part of the AWD gearbox. The front and rear differentials each drive a 20 tooth double bevel gear which in turns drives a 12 tooth double bevel gear attached to the gearbox output axle. So the overall output-wheel ratio is 28:12. I can push the car without problems in all forward gears, but when I put the gearbox into reverse, the 20 tooth double bevel gears and differentials start slipping. When I separate the gearbox from the rest of the car and drive it by hand, I can also feal much more resistance in reverse. In gears 1 to 5 everything feels very smooth. As far as I understand, the different resistance between forward gears and reverse is mainly because of the fact that in reverse 5 of the 6 gears with clutch turn against their axles and in gears 1-5 only one gear with clutch turns against its axle. Now my question is: Is this normal behaviour or am I doing something wrong? And what can I do to make the gears with clutch turn against their axles with less resistance? And a separate question: Appearantly the transfer between the differential and the 20 tooth double bevel gear is the weakest point in my drive train. They are placed in a static transfer box and in a normal arrangement with the double bevel gear placed orthogonal to the differential. Still the differential can move quite a lot. So my question is: Is there a better way to transfer drive to the differential? Hope someone can give me some directions. Thanks! Diederik