SNIPE

nice design, how tight would the bio'nicle parts be in the sockets? wouldn't the outer '+' hub be better if it didn't have the bit sticking out in the middle center as I like having the hub practically inside of the wheel so it is closer to the pivot of the CV joint

I also agree that the 8880 is the best, back then there was few studless parts and they still managed t add lots of gears and mechanisms to it, back when I didn't know better I thought the 8448 was better and more complex but I was wrong. I prefer the studded technic era because you can have any gear combination and the beams can be attached normal or offset without needing connectors.

Perhaps something like this can be used as an automatic switch to drive the other wheel, when the diff kicks in as a closed diff the change in direction can drive the worm gear which goes to another gear that drives the opposite wheel Here is a mock-up of the idea: If this doesnt work try the older diff and put the worm gear onto the gears on the diff. I recon this has massive implementations not just for diffs. Regards, Snipe

Hi, Thanks for the replies, yes its a tri-star wheel I'm after, After trying each idea I think Darsedz' idea is the best as it is the strongest and is fairly centered, so it will either be my original idea or his up to now. I think axles supporting this will be too weak as axles bend easily under load and I couldn't seem to fit a bracket with a hole in-between because the gaps on each point of the triangle is less than 1L. Philos idea looked good but it didnt line up on the last hole needed, it was simular to my original but was less offset. I heard a triangle is the strongest shape which is why girders have that pattern and for a square you'd need more motors, more wheels, more gears/chains

This is for an off roader, each triangle has 3 wheels and there are 4 of them.

interesting idea here I think i'll use it.

Tthat is exactually how I had it prior, maybe I should stick with this and not have it centered perfectly.

Not sure I understand, isnt that the same as this

I'll try that, thanks.

Those don't work either as they are the same as the technic pulley, the three pictures abode line up the same as the pulley maybe I need to change the lift arms

Having something like this or something with the same pin/hole spacing does not work unfortunately my first model used a technic 0.5L thick pulley but that made the model taller than wider by a little bit.

HI How can I connect these three lift-arms in the middle by either the first or second hole? now the triangle shape is a perfect triangle unlike how it was a few days ago but I need to find something that lines up with how the holes are now. Regards, S

My stairs are too high slightly, it could go down them fine but I want it to go over other stuff too (indoors) I think the torque will be too much for gears but I only got some 24 tooth gears and secured them 'lightly' so ill try again soon.

Hi I am making an extreme off roader, the idea is to use a triangular frame connected at the ends by 3x3 T lift arms and connected in the middle by pulleys or a wheel with the right hole arrangement, or this, the triangle frame has a wheel on each point, hopefully Ill get some third party tires when its almost finished however I am not sure how to drive the wheels, now I could use motors connected to 1 wheel for each side as you can just rotate it if you want the driving/driven wheel on the ground but the motor might just spin itself silly instead of spinning the wheel, as in-wheel motors don't connect to the chassis I think gears are a bit odd for this and might get caught on the driving surface, maybe pulleys could work or chains but I'm not sure if its strong enough or the right size. he gears had loads of play in them when I tried with them, it was like they were in a lift arm with holes that were too big! Also the problem with gears is the axle in the middle spins relative to the frame because of the pulleys, this is good as it can rotate the wheels by connecting that axle to a strong motor and hooking that up to the IR receiver. it would have been a little better to have each three wheels spinning but it adds weight and if you did it would change the direction the car moves in if the frame for the wheels rotated. When the whole frame rotates it acts like one big wheel , might be a bit bumpy but still.

Sounds hard to do with lego but I'm sure somebody will do it, there's over 65,000 videos on lego so somebody has probably did it I did see a video on somebody using pins connected to lift arms with pins or you can use the pinholes of a 24 tooth gear, there is not much give here to drive one wheel with the other, maybe a work gear can be used where when it rotates a spur gear so far it connects one wheel's drive to the other but I couldn't put this idea down into lego myself. http://www.youtube.com/watch?v=EtJtRCvUjaE

Check this out: uses band connected to a arm that adjusts the strength of the band which changes how much slip there is

when you get an email from eurobricks from say a forum reply it lists the username in the same email as always, same goes for PM's so maybe there is a way to use this but in reverse but in such a way that unregistered users cannot rend registered users pm's the email already uses some sort of stamp or other way to tell which user replied or pm'd. Ill try flickr. im on virgin instead of BT.

Ah ok, I tried with an M motor a few hours ago, it was terrible, ill try and think of something else :P

reminds me of the Nike one car, definetley a lego first. maybe using the halfire droid wheels would work better as they have teeth on the inside

Hi can I email photos of a MOC or something else to do with lego from my phone to some sort of eurobricks email address such as snipe@eurobricks.com? This would make things a lot easier than having to email it to myself then download it from the email then upload and re size it to tiny-pic then upload it to euro-bricks. Unless theres an easier way? Live/hotmail lets me select 4 sizes before emailing it but eurobricks may have a way to re-size the image after its been added to the post/reply

its hard to say how it will behave without trying it, I only have an M motor and one turntable but the clutch feels fairly strong but not super strong, the driving surface also makes a difference. to put it simply: the motor drives the clutch gear from the center which drives the wheel because the clutch is meshed to the turntable inside, if the car is moving and the wheel is becoming hard to rotate then the clutch might help give it some traction. the turntable is connected to the wheel , edit: sorry, you cant have the axle going through the wheel and the clutch, the wheel is attached to the turntable only.on half with the clutch meshed

The clutch gear is meant to increase torque not slip pointlessly, thats how the clutch drives the wheels, the diff lets them counter rotate, the Tires also help the clutch to stop slipping. Lego is more about trying stuff out and then you can then see what works and what doesnt work, something you cant do in a forum. Im still not sure what on 'demand means', a differential lock? Im not sure how on depand this idea is until it is tried, it may slip too much or not at all, there are a lot of factors involved. I guess you can add gears between the axle for clutch gear and the axle for the motor to give a portal axle., up to 20 tooth wll fit in unless you take the unused half of the turntable away

Wouldnt you be better off hooking the clutch gear to the diff from the inside, its easy to unclip the diff so its in two parts. also I would just have a direct drive system instead of putting a gear on top of the differental as I think the gear will get damaged due to the torque but maybe not, im too scared to try and see :P Instead, I have used a high torque NXT 3 motor in either example, you dont have to add the transparent half of the turntable in the first example with one motor. but the other half of the turntable can just connect to the chassis and doesnt need to rotate for this. The second example should be exxelant for off roading. the motor spins the clutch which spins the turntable however if the wheel gets stuck or whatever the clutch inside of the gear will start to work, you can either attach the wheel to the clutch or to the turntable or both depending on how much strengh you want. You can use other motors if you need more speed but I think torque is more important in lego as the speed is fairly limited.

Won't the 8 tooth gear get destryed? you can easily seperate the turntable so just put the clutch gear inside of that,, close it back up then you can attach the wheel to the turn table mount holes for the black half of the turntable and still use the clutch by putting the axle through it tat goes to the wheel too.you may need to desighn some hub so it can connect to the turntable and the clutch gear, the grey part of the turntable Does Not rotate, it goes to the chassis directly :)

Can't you just use a 1 or 2 24 tooth clutch gear connected to a crown gear which is driven by a motor or is the clutch to strong? I'm not sure what on demand means here.