The Bug 6x6, Rough Sand Trials

[vliet]

Some time later the pictures where the right size. I am almost done building, not completely happy with the colours, but that is not difficult to change.

[Kamil]

All pics in order:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

[vliet]

Please Help,

Because I am using XL motors the offical app with the protocol for the 42129 doesn't recognize de drive motors, after a lot of ugly words which I shall not repeat here. I can't make a test-drive after I thought I was finished.

Greets,

Sander

 

[Kamil]

29 minutes ago, vliet said:

Please Help,

Because I am using XL motors the offical app with the protocol for the 42129 doesn't recognize de drive motors, after a lot of ugly words which I shall not repeat here. I can't make a test-drive after I thought I was finished.

Greets,

Sander

 

Hi @vliet

Have you tried to select 42099 x-treme off-roader from your phone app? Or, if you have the 42099 set, than maybe you can use its hub and motors. I would also be grateful to hear more solutions, if any.  

Edited December 10, 2025 by Kamil

[vliet]

I know I can also use the brickcontroller app, but maybe there are different optioneel

 

[gyenesvi]

29 minutes ago, vliet said:

I know I can also use the brickcontroller app, but maybe there are different optioneel

The profile for 42099 won't work because of the additional gearbox motor..

So you are left with BrickController app or programming with Pybricks (in Python). I guess BrickController is the easier one. I know PU can be irritating when you build it and can't control it..

 

Edited December 10, 2025 by gyenesvi

[vliet]

I have several hubs, I don't know which one is from the 42099 set. In the control+ app the profile of the 42099 won't load. So I will have to try the brickcontroller app, or try to make an program in the poweredUp app. Whis me luck I will keep you updated.

[Kamil]

18 hours ago, gyenesvi said:

The profile for 42099 won't work because of the additional gearbox motor..

High gear is working good in 4x4, but not effective in 6x6 due to high friction. I tried high gear, vehicle cracked and stopped. I thought I have broken red differential case part. However it was the beams (near the front axle) separated sideways under high load. I have re-squeezed the beams into place, and high gear worked again. But this issue is easily repeated. I would prefer to take out the servo motor and connect low gear directly. So, 42099 hub could be used. Otherwise reinforcement may be necessary to hold the beams in place.  

[gyenesvi]

18 minutes ago, Kamil said:

High gear is working good in 4x4, but not effective in 6x6 due to high friction.

Indeed, it's true that as the model becomes heavier, with larger wheels, the high gear becomes impractical, so it might be easier to just get rid of it and then use the 42099 profile (if the steering direction is the right one, the drive direction can be flipped at the diffs if necessary).

@vliet you can test the profile quickly just by disconnecting the gearbox motor!

[vliet]

Thanks for the tips, I will try the brickcontroller app first

 

[vliet]

I am having problems connecting by Switch controller to the brickcontroller app, it has been working before. I have to be more patient to get it to work. I have posted pictures on Gyesenvi rebrickable page. Hopefully the links work. The model is on display during the christmas vacation (from dec 19) at BramsBouwstenen in Breda (NL).

[Kamil]

 Really cool, I like it. A spaceship on the road. Good job 

[gyenesvi]

Looks massive indeed, cool color scheme! I like those snakes on the top :)

What is that Switch controller for? I haven't yet used it I think.

[vliet]

Most people use a PS4 controller with the brickcontroller app, I use a 3 rd party nintendo switch controller. It worked before, I have asked my son how yo connect it. I will try again monday, have to work this weekend.

Edited December 15, 2025 by vliet

[Aurorasaurus]

4 hours ago, vliet said:

Most people use a PS4 controller woth the brickcontroller app, I use a 3 rd party nintendo switch controller. It worked before, I have asked my son how yo connect it. I will try again monday, have to work this weekend.

I recommend ps5 controller over ps4 controller because then you can connect to your phone over a normal usb c to c cable. The ps4 controller uses micro usb which is prone to breaking.

[vliet]

I have made a "program" in the Powerup app, so no need for an controller and the brickcontroller app. One major problem, the motors works like I wanted to, but the car IS NOT DRIVING. The only thing I did different is the differential placed in step 10 of the instructions is an older DBG one not the newer red one. I hope that is not the problem, because I have to take apart a lot. Please Viktor/Kamil can you help me??

When I rotate the driving axle all the wheels rotate an the differential is also rotating so I don't expect it so be a problem.

It looks like the blue and/or tan 20 tooth gear doesn't mesh with the black 12 tooth gear :(  After some puzzling and arguing with myself, I replaced the black 12 tooth gear with a 16 tooth gear and everthing works, it drives, it only makes a weird clicking noise when I start driving in second gear. I am not sure what is changed because the gear ratio is slightly changed 12/20 to 16/20. But is drives well, I will try some "off-roading" / obstacle course later today.

Greets Sander.

I am very glad this magnificient build is finished on time so it can be in the museum this christmas vacation (from december 20th) at Brams Bouwstenen in Breda (NL), many thanks to Gyesenvi and Kamil. I will post some more pictures soon.

 

Edited December 15, 2025 by vliet

[gyenesvi]

1 hour ago, vliet said:

The only thing I did different is the differential placed in step 10 of the instructions is an older DBG one not the newer red one. I hope that is not the problem, because I have to take apart a lot. Please Viktor/Kamil can you help me??

I think that should be fine, the old grey and the newer red ones are identical I think. Does the clutch piece engage it properly? Did you check the orientation of the orange wave selector, with respect to the limiter connector piece, and wrt the sliding shifting piece? When the connector in the front is pointing upwards, it should be in neutral gear.

1 hour ago, vliet said:

It looks like the blue and/or tan 20 tooth gear doesn't mesh with the black 12 tooth gear :( 

Now that's weird, that is a very standard gear mesh, it should work. In fact, replacing the 12T with a (thin?) 14T should not work. Something seems off there.

[Kamil]

2 hours ago, vliet said:

I have made a "program" in the Powerup app, so no need for an controller and the brickcontroller app. One major problem, the motors works like I wanted to, but the car IS NOT DRIVING. The only thing I did different is the differential placed in step 10 of the instructions is an older DBG one not the newer red one. I hope that is not the problem, because I have to take apart a lot. Please Viktor/Kamil can you help me??

When I rotate the driving axle all the wheels rotate an the differential is also rotating so I don't expect it so be a problem.

It looks like the blue and/or tan 20 tooth gear doesn't mesh with the black 12 tooth gear :(  After some puzzling and arguing with myself, I replaced the black 12 tooth gear with a 14 tooth gear and everthing works, it drives, it only makes a weird clicking noise when I start driving in second gear. I am not sure what is changed because the gear ratio is slightly changed 12/20 to 14/20. But is drives well, I will try some "off-roading" / obstacle course later today.

Greets Sander.

I am very glad this magnificient build is finished on time so it can be in the museum this christmas vacation (from december 20th) at Brams Bouwstenen in Breda (NL), many thanks to Gyesenvi and Kamil. I will post some more pictures soon.

 

First issue: All differentials in opposite directions? When looking from the bottom side (front is up), front axle first differential main gear is at the left side. Mid axle differential is at the right side. Rear axle diff. main gear is at the left side again. 

Second issue: It is the mentioned issue before. Check bottom beams between the two L motors and the front axle. Squeeze them if you find them separated apart. This gear can only be used when the surface is flat, and vehicle is at complete stop. Start giving low throttle while on start.

Happy you have applied (or trying to aply) new gear ratio. 

All the best 

Edited December 15, 2025 by Kamil

[vliet]

Viktor and Kamil,

Thank you both for the Quick reply, maybe because I used the XL motors I had to change the gears and because of that there is a small gap between the gear. I tested it and it looked ok. I know it is not optimal to mesh a bevel gear with the 24 tooth gear, but is seams to work fine now.

I had checked the orientation of the diffs, that was ok. I have made and error like that before on another build. The 6x6 drove nice this morning, with all wheels in the same direction, it was a short drive, because it was on my desk.

Greeting and thank you,

Sander

 

 

[vliet]

I just tried to drive over some obstacles and my gear ratio did not work. I now replaced both (tan and blue) double bevel gears with the newer dark azure 20 tooth gear and driving is something better, when driving over and obstacle like my fist I hear some clickling/rattling noises coming form the gears so some improved is needed.

 

[Kamil]

Inspired by your work, I had a chance to re-work on this vehicle at the weekend. As I have limited choice on colors, I asked a Ferrari designer to create a road version of the bug 

 

 

 

 

 

 

 

This vehicle has nearly same dimensions as Lego 8448 Super Street Sensation:

 

 

 

 

Edited December 15, 2025 by Kamil

[vliet]

In Red it also looks very nice, I really like the small panels in the front, unfortunately I don't have those in lime green.

I solved the problem with the driving gears, since the axles gears are all in the same height, the solution was easier than I thought this morning. I now used 5 16 tooth gears in one row. The overall gear ratio remains the same and the weird clicking noise in 2nd gear is also gone, and no problem when driving over obstacles in 1st gear. I used an extra beam between the motors and the gears and I had to change the axles off the gearbox because the construction is now 1 stud/beam longer than it was.

 

[Kamil]

13 minutes ago, vliet said:

In Red it also looks very nice, I really like the small panels in the front, unfortunately I don't have those in lime green.

Thank you, White may be? I am looking forward to see how it goes with XL motors. 

All the best

[Kamil]

Front windscreen area of the 6x6 Bug is redesigned, an openable windscreen is added:

 

 

All the best