42099 - 4x4 X-treme Off-Roader

[JackBloomer5]

Does the 42099 release in July or in August? I wasn’t planning to buy it but crazy new parts and grad money changed my mind. Also, do we know if there is a 28 tooth gear in the model?

[AVCampos]

45 minutes ago, JackBloomer5 said:

Does the 42099 release in July or in August?

August. 42100 will be in October.

[nerdsforprez]

2 hours ago, Didumos69 said:

 

I wonder how the rotation speed of the new XL motors compares to the rotation speed of the PF medium (405rpm) and PF XL motors (220rpm). Given the 5:1 gear reduction, I suppose/hope it's closer to 405rpm than to 220rpm.

Pure speculation, but based in the speed of the model in the video, i think it is closer to the 405. If around the pf xl motor, at 220 rpm and 1/5 gear reduction, it would move slower. 

[Zerobricks]

56 minutes ago, nerdsforprez said:

Pure speculation, but based in the speed of the model in the video, i think it is closer to the 405. If around the pf xl motor, at 220 rpm and 1/5 gear reduction, it would move slower. 

The XL motor is geard up two times by 20:12 gear ratio, than it goes to a diff, 28:20 and than to the hubs. Total gear ratio should be around 1:2,52

[1gor]

3 minutes ago, Zerobricks said:

The XL motor is geard up two times by 20:12 gear ratio, than it goes to a diff, 28:20 and than to the hubs. Total gear ratio should be around 1:2,52

Sounds reasonable (if we ignore reduction in wheels hub itself). I'm curiously awaiting first review and impressions.

BTW you were right about hub reduction. 

Edited June 16, 2019 by I_Igor

[Didumos69]

12 minutes ago, Zerobricks said:

The XL motor is geard up two times by 20:12 gear ratio, than it goes to a diff, 28:20 and than to the hubs. Total gear ratio should be around 1:2,52

In that case I think the new XL motor has about the same rpm as the PF XL motor.

Altogether the gearing up of the motor and gearing down in the wheel hub fits exactly my theory on how to avoid slipping gears and twisted axles in the drive train / differentials: high rpm / low torque instead of low rpm / high torque.

[TeamThrifty]

you have some time away and come back to new parts! I'm unreasonably excited about the planetary's.. i've got some plans for those.

What the best guesses for prices for this and 42100? I've some numbers mentioned but not sure how reliable they were.. seemed pretty strong money.

[Snorrowitz]

On 6/15/2019 at 4:50 PM, Jim said:

On 6/15/2019 at 7:27 AM, Ngoc Nguyen said:

It is a new color.

Yup, it is. And I stand corrected. Dark Yellow is what they called it, if I am not mistaken.

Is it? I happen to be building the 42096 Porsche today an I noticed that the yellow of the cilinder heads an crank shaft end pieces are a darker yellow than normally. Might it be the same as the "new" technic color?

[HorcikDesigns]

I am not sure, whether this question was asked and answered before, in case that they were, please delete this post.
Are the gears inside the planetary wheel HUB made from plastic, or metal?

[nerdsforprez]

7 hours ago, Didumos69 said:

In that case I think the new XL motor has about the same rpm as the PF XL motor.

Altogether the gearing up of the motor and gearing down in the wheel hub fits exactly my theory on how to avoid slipping gears and twisted axles in the drive train / differentials: high rpm / low torque instead of low rpm / high torque.

Agreed.  I forgot to account for the gear train prior to the hubs. 

Which, if we are right, is unfortunate.  I won't complain too much, I think AFOLs are getting quite a bit from these two sets in terms of new parts/motors/control system.  However, a faster XL would have been nice and a quite obvious choice to anyone that has paid attention to AFOLs voice over the past few years. 

[Attika]

2 hours ago, HorcikDesigns said:

I am not sure, whether this question was asked and answered before, in case that they were, please delete this post.
Are the gears inside the planetary wheel HUB made from plastic, or metal?

I'm not sure anyone knows yet. My take on it, that TLG already have a well prooven planetary system in the PF motors, despite being plastic, it seems to hold up quite allright. So my bet is on plastic. 

[Anio]

Full plastic, I think.

Plastic might be damaged with metal parts.

[z3_2drive]

Nice parts! Progress like this almost makes me want to come back to Lego and snag this set just to test the possibilities. Do those new CV joints snap together so the pins are captured tightly or....

I wonder if Lego considered a dogbone design, they seem to handle a lot of torque but axles sliding out of the differential and friction wear might be too problematic.

Edited June 17, 2019 by z3_2drive

[andythenorth]

7 hours ago, Attika said:

My take on it, that TLG already have a well prooven planetary system in the PF motors, despite being plastic, it seems to hold up quite allright.

Aside: the planetary also isn't restricted to being used as a wheel hub   We now have a compact inline gearbox for any purpose.   

[TeamThrifty]

4 minutes ago, andythenorth said:

We now have a compact inline gearbox for any purpose.

An excellent point, there's also the linear clutch..  very compact main reduction. I love building tractors which use planetary's on the axles, so this is new 'realism' part. I often down gear more than 5:1, so being able to add one at the motor in such a small space will be awesome.. Lets also see how the clutch performs, maybe better than the old white 24 version?

Can't wait for the new parts to appear on brinklink or similar. 

[Cumulonimbus]

Perhaps this is obvious for experienced crawler builders here, but I'm curious what the advantage is of a planetary gear reduction in the hubs in a Lego model? Why would you want to do the final reduction in the hubs instead of in a gearbox? Is there a mechanical advantage or is it just fun to copy real world machines?

[keymaker]

22 minutes ago, Cumulonimbus said:

Perhaps this is obvious for experienced crawler builders here, but I'm curious what the advantage is of a planetary gear reduction in the hubs in a Lego model? Why would you want to do the final reduction in the hubs instead of in a gearbox? Is there a mechanical advantage or is it just fun to copy real world machines?

 

Maybe I am not so experienced builder like others here but as far as I know you try to keep high speed - low torque as long as possible to protect any vulnerable parts like for example cardans and CV jonts. Such a big reduction located basicly into the wheel gives you a great posibility to follow this rule.

[Bartybum]

I imagine that’s precisely it. The stronger the torque load path, the more stressed all the components are.

[Didumos69]

1 hour ago, keymaker said:

Maybe I am not so experienced builder like others here but as far as I know you try to keep high speed - low torque as long as possible to protect any vulnerable parts like for example cardans and CV jonts. Such a big reduction located basicly into the wheel gives you a great posibility to follow this rule.

This is exactly the point! 

2 hours ago, andythenorth said:

Aside: the planetary also isn't restricted to being used as a wheel hub   We now have a compact inline gearbox for any purpose.   

I don't entirely agree. Because of the tentacles of the static part of the hub, it won't be possible to make it very compact. You cannot make a simple single gear mesh gearbox, the driving ring would collide with the static part of the hub.

10 hours ago, nerdsforprez said:

Which, if we are right, is unfortunate.  I won't complain too much, I think AFOLs are getting quite a bit from these two sets in terms of new parts/motors/control system.  However, a faster XL would have been nice and a quite obvious choice to anyone that has paid attention to AFOLs voice over the past few years.

Exactly.

Edited June 17, 2019 by Didumos69

[Seasider]

I’m liking this set more and more. Definitely interested in how the clutch piece works

[allanp]

1 hour ago, andythenorth said:

We now have a compact inline gearbox for any purpose.  

Which is great. This also makes me think that there is even less need for the motors to come with so much internal gear reduction. In the case of 42099 I believe the XL motor is geared up before going to the differential then geared down again in the wheel hubs. So essentially there is the XL internal motor>internal gearing down>gearing back up again>gearing back down again. Not only is this unrealistic and incredibly inefficient wasting a lot of power but is also means that all of the gearing down is done in pre-built assemblies, which is very not Lego, and feels very overly simplified and childlike for a set aimed at teen builders. Having a motor with very little to no internal gearing solves these problems while still having those lovely new planetary reduction hubs. You might say that this reduces wear, but when you are gearing up after the motor that becomes a moot point. So while we have a selection of motors surely there is room for just one very fast and quite powerful motor in the lineup. Must they all have so much internal gear reduction?

[Cumulonimbus]

2 hours ago, keymaker said:

Maybe I am not so experienced builder like others here but as far as I know you try to keep high speed - low torque as long as possible to protect any vulnerable parts like for example cardans and CV jonts. Such a big reduction located basicly into the wheel gives you a great posibility to follow this rule.

Sounds logical, is it also true that the impact of the inevitable backlash in a Technic drivetrain is smaller in a high speed system?  This could mean that for example the amount of roll-back after stopping on a hill is limited? I understand why you would want a low torque high speed drive train, but I imagine that the drawback is increased wear on axles and gears (the dreaded white powder)?

[keymaker]

16 minutes ago, Cumulonimbus said:

Sounds logical, is it also true that the impact of the inevitable backlash in a Technic drivetrain is smaller in a high speed system?  This could mean that for example the amount of roll-back after stopping on a hill is limited? I understand why you would want a low torque high speed drive train, but I imagine that the drawback is increased wear on axles and gears (the dreaded white powder)?

Yes, the minus of such solution is bigger backlash, also of course the wearing of axles and gears is slightly bigger. But this two things are much less impactful than possibility of broke CV joints/cardans, gears slipping or axles twisted due to too much torque. You also should remember, that decreasing of torque by the half is a big thing and it has a huge impact on parts, when increasing the speed by two - basically no impact on parts.

 

To sum up, you gain a lot with very low cost.

 

Edited June 17, 2019 by keymaker

[Bricktrain]

1 hour ago, allanp said:

Which is great. This also makes me think that there is even less need for the motors to come with so much internal gear reduction. In the case of 42099 I believe the XL motor is geared up before going to the differential then geared down again in the wheel hubs. So essentially there is the XL internal motor>internal gearing down>gearing back up again>gearing back down again. Not only is this unrealistic and incredibly inefficient wasting a lot of power but is also means that all of the gearing down is done in pre-built assemblies, which is very not Lego, and feels very overly simplified and childlike for a set aimed at teen builders. Having a motor with very little to no internal gearing solves these problems while still having those lovely new planetary reduction hubs. You might say that this reduces wear, but when you are gearing up after the motor that becomes a moot point. So while we have a selection of motors surely there is room for just one very fast and quite powerful motor in the lineup. Must they all have so much internal gear reduction?

Funny how many complain about not enough gears in a set, now we have unnecessary gears too. LOL.

[Didumos69]

Just now, keymaker said:

Yes, the minus of such solution is bigger backlash, also of course the wearing of axles and gears is slightly bigger. But this two things are much less impactful than possibility of broke CV joints/cardans, gears slipping or axles twisten due to to much torque. You als should remember, that decreasing of torque by the half is a big thing and it has a huge impact on parts, when increasing the speed by two - basically no impact on parts.

 

To sum up, you gain a lot by very low cost.

Again,  for this reply.

9 minutes ago, Cumulonimbus said:

This could mean that for example the amount of roll-back after stopping on a hill is limited?

Roll-back is more evident on a flat surface when you switch directions. In your example the drive-train is already wound-up while climbing the hill and will remain wound-up when you stop.