Is there any need for a new differential design?

[Richard Dower]

just wondering if anyone see a need for a new type of differential?...we have had 3 types over the years but nothing of a major redesign, save for some minor mould updates.

what would a new design look like or what attributes would you like to see?

[Alasdair Ryan]

I do not see a need myself,if you need a stronger diff you can build a custom one.

Remember that Lego Technic parts are not meant to be "abused" by the way some builders use them in some of there creations.

[allanp]

Well, I'de like one like this:

Basing the crown wheel on a 36t double bevel gear gives a much better 3:1 reduction and allows it to be driven by a bevel or by a spur gear. The design of the 20 tooth bevel gears that goes onto the axle drive shafts has a full 1M thickness for strength and really helps to eliminate the issue with the axle sliding out the gear causing loss of drive. Also, by having 4 inner gears as opposed to 3, and by having them all have a full 1M thickness, this greatly increases the torque capacity to over three times that of the current differential, by my guesstimation. Flagship sized cars having large diameter wheels and no reduction after the differential place lots of stress on the differential. This differential would allow for motorised flagship sized supercars and offroaders. I would also like to see a new larger 8880 style low friction CV joint to go with it.

Edited August 7, 2015 by allanp

[Alasdair Ryan]

Well, I'de like one like this:

Efferman has a design very similar on shapeways.

http://www.shapeways...signer/efferman

I cant see lego making a new style diff like this.

Edited August 7, 2015 by Alasdair Ryan

[Anio]

we have had 3 types over the years but nothing of a major redesign

Even width to odd width, a minor redesign ? Oo

It is a major and welcome change for studless construction.

[kolbjha]

Basing the crown wheel on a 36t double bevel gear gives a much better 3:1 reduction and allows it to be driven by a bevel or by a spur gear. The design of the 20 tooth bevel gears that goes onto the axle drive shafts has a full 1M thickness for strength and really helps to eliminate the issue with the axle sliding out the gear causing loss of drive. Also, by having 4 inner gears as opposed to 3, and by having them all have a full 1M thickness, this greatly increases the torque capacity to over three times that of the current differential, by my guesstimation. Flagship sized cars having large diameter wheels and no reduction after the differential place lots of stress on the differential. This differential would allow for motorised flagship sized supercars and offroaders. I would also like to see a new larger 8880 style low friction CV joint to go with it.

I like your design, certainly much more robust than those available today. But I am not sure if cross axles will be able to handle the same amount of torque.

[miguev]

I'd super-love to see LEGO making a torsen or limited-slip diff.

[PacmanRacing]

Huh...I don't know if we need a new one... :/

[JJ2]

Well, I'de like one like this:

+1

[LennyRhys]

I agree with kolbjha re. allanp's proposed design - it's really nice, but if you want a differential to handle significantly more torque than existing differentials you'd almost need to redesign the entire transmission system from the ground up, because axles themselves don't handle torque particularly well... certainly not on large scale models. I was taking a model apart just the other week and a 6L axle was twisted by several degrees because of the torque in the gear train. The axle is now useless and needs to go in the bin. Let's not forget that Lego is, first and foremost, a toy!

I definitely prefer the original style diff that can be driven edge-to-edge or at 90 degrees, however a bigger sprocket on the outside has its own limitations and I've been snookered by this in the past, which is why I often used the newer diffs in my MOCs. 42030 is my very first experience of the newest style of diff with the external bevel gear, so I can't really comment on that as I have yet to try it in an MOC.

[aeh5040]

Even though it may not be the best for vehicle transmissions, I'm a big fan of this one:

- the spur gears on the housing are great for add subtract mechanisms and their many variants...

Edited August 8, 2015 by aeh5040

[kolbjha]

I mentioned above concerns about torque with the cross axles of today, if used with new and more sturdy diff, but another significant advantage IMO with allanp's design is less backlash, thus more precise mechanics.

[CP5670]

Even though it may not be the best for vehicle transmissions, I'm a big fan of this one:

- the spur gears on the housing are great for add subtract mechanisms and their many variants...

Yes, this version is certainly the most versatile. The current 3-wide one is good as an actual differential but much harder to use for other purposes.

[Nazgarot]

I think the designs we have are good enough, but I would like to see them with 4 rather than 3 bevels as that would make them much stronger. I guess the reason they only come with 3 is the difficulty of mounting a 4th bevel... That probably also is the reason we never will see one with 4, after all it's made for kids... Luckily it's quite easy to modify the existing 4 l design to have 4 bevels.

-ED-