mescalinum

also the worm it is not efficient as spur gears, due to greater friction

thanks! finally I have my whole collection in the database (except for spare parts i bought on BL) one another question: does it handle "counterpart" relations? i.e. when a wheel in a set is mentioned as 1 piece (complete assembly), and in another is mentioned as 2 piece (inner wheel and tyre) for example when trying to build Lamborghini Gallardo it says I miss 4x 32495 and 4x 32496, but of course I have the 8070 set, and bricklink reports has 4x x873c01 which should be the same, isn't it?

yep I use leJOS NXJ so I can write my programs in Java, but there are also firmwares that allow you to write in C if you prefer it

welcome to the forum! hmm, maybe it is inefficient -but I'm not 100% sure- as there will be a motor which is slightly slower, and one which is slightly faster, which will be limited by the slower one. making an adder -using a differential gear- is the proper way of adding the power of two motors (although it introduces the friction of differential gears) you should try both, and don't forget to report your findings once you've done

thanks! I believed it was some rare part, instead there are tons of them

I received it two days ago. it has been quite fun to build (built time approx 3 hours and a half) now I'm planning on removing the motorized functions (useless to me), maybe putting in a real gearbox, change the chassis, and perhaps make it black! (but are there black panels around, like 17 18 13 14?)

hi all, I've got this piece can't find it on the bricklink catalog. any help? if I remember correct, should be something really old (80s or even 70s)

I love those multi-sized compartment boxes, very space effective!

about torsen differential, when used between wheels, does it suffer of the problem pointed out by tripletschiee ? I have not much understanding on how it works, but it seems the answer is yes... but for a rally car would be reasonable

good point, in fact, considering those corner cases, you cannot make such a autonomous differential lock. in my system, the only guarantee that it will work correctly (that is: the treshold that activates the diff-lock) is the amount of slip VS time: * slipping (due to a real slip condition, or simply a curve) makes the pneumatic pump work, causing the diff-lock to engage at some point * the rubberband makes opposite work, pushing the pneumatic piston back, causing the diff-lock to disengage * the pneumatic hose has a small leak (made on purpose) that allows the air to slowly leave the pneumatic circuit now you can conclude that: if the pump pushes air fast enough (faster than the air leaking due to pressure + rubberband force), the diff-lock engages/stays-engaged; otherwise, it means that is leaking more air than what is "pumping in", so the diff-lock will at some point disengage/stay disengaged. is it clear? so, in the "real" world, in the parking house, the slip detector will slowly pump air in the circuit, and the diff-lock doesn't reach its "activation treshold". in the case your truck gets stuck in the offroad terrain, where one wheel is lift, the truck driver begins hitting on the accelerator, and it happens quite fast that enough air goes in the circuit, causing the difflock to engage, serving its purpose of getting out of that slippery situation :) from a technical point of view, it is all about making equilibrium between 2 forces (pump and rubberband), all dumpened by a certain factor, determined by the dimension of the leak (that is probably the crucial part to calibrate if you want perfect functioning) and of course, this is Technic, so it's hard to get perfectly working stuff small MOCs, yes. check my brichshelf home (I also have something on youtube of which I didn't make cad representation, for various reasons) it's not exactly MOCs in the common sense. I just like robotics, mechanisms, and small ideas.

as Illuwatar pointed out, differential is beneficial for normal driving (you'd rather have problems *without* it). but there are side-effects you can get stuck into, like for example when a wheel begins to slip because has lost contact with terrain. the differential lock is meant to be temporary, and should disengage automatically just after the axle has stopped slipping. (the use of pneumatic is meant to introduce some delay and avoid oscillations between the two states) EDIT: I produced building instructions for it (quick & dirty, there are a couple of inaccuracies but nothing fatal) you can get it here (pdf) or in my brickshelf folder as soon as it becomes public

without pneuumatics you can build a differential that doesn't lock, but offers some resistance to slip, i.e. when an axle is in condition of slipping, some resistance (clutch gear?) on the slip detector still ensures that some force goes to the other (non-slipping) axle. I had to use pneumatics because they introduce a delay which turns to be useful, when exploiting the force of the slip detector to engage the differential lock I hope that was clear.... that's what I can do at 1.30am tomorrow maybe I will make a try for sure, such a design would be simpler than the pneumatic

on the technicbricks blog

those aluminum parts are damn cool! I want so much a machine for drilling my custom aluminum parts (sorry purists )

while I wait for the parts & sets I just bought, I decided to try to implement a self-locking differential (I made a search on the forum, and apart from sariel's "limited slip" differential, I found nothing else). the key point of this is the slip detector, which makes use of a second differential to detect slip (in fact, rotates proportionally to the main differential's slip). on top of that, one could implement various concepts (for example putting friction on the slip detector, would make a limited slip differential -note I've put that in italic, because it would be limited by force means, and not by amount of slip- ) what I implemented instead is a pump+actuator(pneumatic) based design, with a rubberband to disengage the lock when there is no more slip (NOTE: the pneumatic hose has to have a little leak in order to allow that). honestly, I was hoping to make it smaller, by the way this is the very first prototype, and I don't have the small pneumatic cylinder... and I'm posting here to hear some feedback from you, maybe someone could improve over my design (cad file will follow...) c'mon, comment!

thank you all :) heh I was hoping something like 8070... btw I learn on technicopedia that x873c01 is the only recent steering gear, and earlier variants are quite uncommon your yellow supercar looks very nice... let's see if I can get it... nice pick! it has almost everything I need. it seems I can just buy the racing tires separately (Black Tire 68.8 x 36 ZR), as the wheel is the same as 8070 and others yep I'm member of Rebrickable. after I buy the missing set, I'll be able to build some supercar :)

Hi all, I'd like to build a supercar (mainly studless), and I need an advice on which pieces/sets to buy. I've got plenty of studded bricks from 80s/90s (but no supercars), then didn't buy technics for a while, and then I discovered studdless models with 8043 (new), then I bought 8455 and 8547 (used), so now I have a minimal assortment of studless pieces. What I need to get now is the pieces needed for a supercar, that is: wheels, suspension mechanisms + steering + joints, maybe the 3rd version of differential (I have the second version anyways). I could also buy a whole supercar, but I prefer to expand my yellow and black (studless) palette, rather than starting with red pieces as well... didn't TLC make a black/yellow supercar recently? I suppose the 8880 mechanisms would go as well, but here it costs (used) more than it's worth. What's your advice? I see there are different steering/suspension/wheel attachment mechanisms, which one you prefer? Or which supercar you prefer, thinking to the abovementioned mechanisms? TY