Leif

Today I caved in and choosed the portal hubs.... At least I know the reason why I have to do this. Making the steering and the hub powerful enough, I could at the most save ½ stud compared to just mount it all on a portal hub....too much bracing and brick next to brick to get the results (ackermann, no bump, sturdy!) Yeah, pivots for steering are not optimal but I have to avoid those dreaded CV joints...at least for this crawler/monster! So now I got strong setup, good gear down after differential which should mean no/less grinding. But first, London and Bricks 2014 for some days now

thanks, I got the 42000 hubs, 8466 hubs and some more, but CV = breakage! there is no way you could build a strong crawler with huge tyres and CV joints... My build has to be with UV joints and centre point steering must be "as good as possible" due to the build around thoise joints. The race hubs with CV are always the best solution for steering geometry but they wont last when it comes to forces being applied...

of course but that would mean wider chassi and/or the dreaded portal hubs...

Thanks, btw I apologize for posting half done things in the axle thread, this thread should, I think, mostly consist of finished, proven, designs. not ideas! I have done some redesign now and I risk getting into "half stud galore" with the setup. Got some ideas still to build and test with wheels and tyres, and I think this is one of the best, when finished, when it comes to geometry, which I aim for really hard.

This is something I been cooking up the last days. It is also one of my first creations in LDD so bear with me LXF file is included at the bottom, link to my dropbox. please let me know if troubles or if something can be made easier. Fully independent and driven. strong - no CV joints! Ackermann geometry. No bump steering, all geometry aligned. Ideas stolen with pride from several posts here at the forum, SNIPE among others, thanks! Still, some ideas I think are my own Room for improvent, steering links are unnessacary high and wobbly but I had to move away from differential, can be redone and maybe will be! Steering geometry can be placed really near wheel hubs, even PP wheels and tires. This was a mandatory demand from me. I have build it as well and I am in progress of the second, duplicate (mirrored) in order to build a crawler so we will see outcome of real life build quite soon I hope. https://www.dropbox....ering3.lxf?dl=0 Edit: Improved it right away (in theory) and added some missing axles!

Snipe, your setup has really inspired me and I have learned some new techniques. Finally! But I gotta ask, the setting above, is it final? as I see the pic, the inner UV joint does not align with the pivot of wishbones, right? Also, the 4L width setup of wishbones is great but the inner connection of wishbone are they really 4L? I cant do the math from the pic...

This is a trial build I did. It maxes out some things I wanted to finish. For example 5 studs is more or less maximum inside a wheel hub (aiming for 8466 PP wheels!) some hinges are too weak so this is probably not the best solution, but at least it is now in print.. Some smaller improvements can of course be done in this example, reorder or replace some thin beams, also one or two reinforcements would require 2.5 axles... but my building knowledge would not stretch so far so I would be able to build anything sturdier given the area restrictions. If you settle with building most of the construction outside the wheel hub then of course you are not restricted to 5 studs or anything. steering geometry will not be the best.. well maybe that is not priority one when building a crawler or monstertruck so I may have to do some small compromises in this area. Still, thank's a lot for all tips and I got some real good examples to study tonight!

I've been searching high and low for examples of a 4x4 truck with: 4x4 strong (2x XL as power or similar) big tyres, crawler or unimog size Independent suspension, not live axles this time! and not Tatra this time either.. usable! good steering geometry and pivot points (not portal hubs..) So far all the examples always feature the (dreaded?) CV joint and it is not hard to find info about them and at the same time find info about how easy they break... Building something with the (dreaded?) portal hubs could be a solution but then we are back to hopeless steering geometry! I have looked through all the LPEPowers excellent, really excellent(!) youtube videos of different solutions. Did I mention they are excellent? Episode01 and youtube will more or less guide you through the followups: Still, as far as I can tell, I have not been able to find that really good example of something with a really strong drivetrain? cardan joints are more or less mandatory and suspension/steering may demand CV instead, is the project a dead end? or maybe some small compromises would take me forward? I would really dislike to build that cool 4x4 with big fat tyres and 5 minutes later have to disassemble and take to the garage for CV joints replacements... any ideas anyone? A lot of thanks in advance

yep, downloaded. thanks a lot! now study..

you can share quite easy using dropbox/onedrive and similar services. If you don't have any of those storage solutions you might just as well sign up, always good to have!

Yes please, if it is not a problem for you.

snipe + 42029 at google :) http://www.eurobricks.com/forum/index.php?showtopic=99726

not at the moment but if it's handy I would love to look into your ideas! Sounds like something really good. Do you have an url in the right direction to give me?

That is sturdy! I "only" have 7 turntables so I guess I cannot finish yet. I will follow your thread and build with interest!

well, that would be a quite proprietary solution and the 8880 has some friction issues .not a bad idea though and I just read up on the 8880 on the techniopedia. excellent machine and to think it is 20 years old!

I am a computer guy, Freudian slip you know

not too bad! I guess the doohickey on top is a replica of a PF server motor

I asked the same question but got moved, no worries, the few answers we got you can find in my thread. http://www.eurobricks.com/forum/index.php?showtopic=101362

Gents, bear with me. this is my first MOC in 30 years Cranes then and cranes now, but for the time being just the sub structure. My plan is to add the nowadays more or less standard Ultimate 42009 superstructure together with afol1969 boom, modified by myself some time ago, making third part of the boom stronger, described here http://www.eurobrick...00#entry1996084 This is an 8x8x8 all wheel driven, all wheel steered. I skipped suspension this time, got my hands full with the build anyway and it would take some time to figure out a sturdy suspended structure. I stayed with the portal hubs although they have some issues concerning steering geometry. The machine is driven by 1 XL PF and it seems powerful enough as well as modest speed, good for a crane. steering is PGA technic - Pretty Good Ackerman and as a matter of fact, the machine passes the carpet test I had a different gear ratio to 2nd and 3rd axle and that one did not pass the carpet test so I've been there and back. I also had a weak drive train in first version, grinding where I fed first diff from engine from time to time, but still it passed the carpet test without any grinding so I would like to call it flying colors - so far! adding weight may prove something else.. this is a ver 1.0 and the build is already improved right after pics taken so please share any insights or recommendations but I am might be on some of them Wheel colors are of course temporary, If I finish I may invest in some to get get color matching! Overview: backend frontend Steering! Belly shot old and bad version of drive train and engine new and improved drive train!

Well a pic says more than a 1000 words But apparantly I had a brain fart on axle 1 and 4 since they have not compensated for this on axle 1 and 4. only on axle 2 and 3. I know why, I took a last minute decision to change the width of the vehicle and for some reason forgot to rebuild steering rack! oh well, not in production yet so no recall needs to be done

Well, you could say I',m bumping an old thread but it is my own so I figure it's ok New and improved version of this 8x8x8 chassi. Steering has been simplified using one single train of axles across the entire structure and racked gears with different distance instead of different gearing. Steering motor is temporarily installed though. Motors have been better integrated into the chassi. 2x XL hard coupled geared down 8:24 - 12:20 -12:20 (diff) and finally 20:28 (portal hub) Colors have been sorted out! The machine is strong as a horse! Steering has been upgraded to RGA - Really Good Ackermann and passes the carpet test, with load, with flying colors! and having the Unimog Tyres along with portal hubs and still have decent Ackermann - I'm proud! Still - this is probably the end of the line for this machine. I have learned a lot and, being a quite new AFOL, I am still in the learning curve. My next project might be some kind of crawler and I will probably build 1 or 2 of Madoca's excellent MOCs in order to pick up some ideas and insights I have analyzed and taken notes of my building technique compared to proper MOCs and I know, and have concluded that I still build the old way - bottom and up, instead of the new no studded technique - from inside to out. That is, I build a chassi and try to cram in the motors rather than building a drivetraing and get a good chassi surrounding this. However, I know that my machines are quite sturdy and with good bracing, but I have to rebuild so darn many times due to not being able to foresee needs in the structure! need to change tactics sooner or later! Oh well, some closing pics of the machine. As said, 8x8x8, Ackermann, Portal hubs. 2 x XL driving. strong as a horse!

thanks! While we are one the subject of booms, what would this be called? the boom can be "knuckled" as you can see. It is called "city boom" in Germany I've heard, due to shorter total length while transporting. Anyone up for a MOC with this construction..?..

The 8455 is quite generic but the stabilizers are definitely JCB. The stabilizers are actually something where you can spot the difference between models, since the digging rack is quite generic even in real life. Then of course you have the Danish Hydrema and Swedish Huddig with actuated steering and the more rare models where the entire digging rack can be located sideways... What would really make a cool replica is to incorporate the tilting mechanism that some diggers have between boom and stick. i have no idea what is is called, except in Swedish...

I actually have 1 or 2 gray 8 tooth that slip off axles just like the unique red 8 tooth from the 42009. I'm mighty proud of them because they are rare...but in the wrong context, they are way wrong for their purpouse..

you are most welcome and good luck with your project!