25 replies to this topic

[Sicil]

Hello. I want to present you a model to Technic Rally. In it, I tried to combine the speed, patency and low weight. Initially, the model looked different and many times being finalized. I present to you the final version of the model.
Datasheet:
- 2 M-motor to the drive  with gear 3:5
- Servo motor on the steering
- IR receiver  a new type, BB


















That's all. Thank you for your attention. Your Sicil. Sorry for my bad english

Attached Files

•  Rally car Blacked.lxf   44.56K   61 downloads

Edited by Sicil, 17 November 2012 - 06:26 PM.

[DLuders]

This is a great little Lego Power Functions rally car!  It is quite fast, and your pictures are detailed enough that people could probably build one just like it.  I like how you used the Lego Technic Seat and the Technic Figure.

[timslegos]

That is one fast car!  Nice job.

tim

[Gear)]

Really nice car, i like it)

But, it a little bit not in scale with technic figure (last foto)

[Azzepa]

Looks pretty awesome,  I like that it is small, compact and fast, quite a speedy little thing, and as David seems to have pointed out, it does somewhat resemble a Range Rover.

Good job

[rm8]

DLuders, on 03 November 2012 - 05:26 PM, said:

This is a great little Lego Power Functions rally car!  It is quite fast, and your pictures are detailed enough that people could probably build one just like it.  I like how you used the Lego Technic Seat and the Technic Figure.

David can always find real analog:) dont know what to build that David cant google...:D


I have only one question: if you have 9398, why dont you use more torquey L- motors for drive? You can change gears for faster speed with L's. cccc

Edited by rm8, 03 November 2012 - 09:32 PM.

[Azzepa]

rm8, on 03 November 2012 - 09:31 PM, said:

I have only one question: if you have 9398, why dont you use more torquey L- motors for drive? You can change gears for faster speed with L's. cccc

But Sicil used 2 M motors for drive, and as 9398 comes with only one L motor (I think, don't own it yet myself. On the wish list though ), that would pose a problem, and then there would be a need to get another L motor. Probably not as convenient as using what you already have.

Correct me if I'm wrong though. And it depends how much you want to stick to the original design as well I suppose...

[Phoxtane]

Azzepa, on 03 November 2012 - 09:38 PM, said:

But Sicil used 2 M motors for drive, and as 9398 comes with only one L motor (I think, don't own it yet myself. On the wish list though ), that would pose a problem, and then there would be a need to get another L motor. Probably not as convenient as using what you already have.

It's got two, one for each axle. I think the problem is that the L-Motors are longer than the M-Motors, so the frame would have to be widened to get them to fit.

[Sicil]

Thank you all for your good comments.  I started to build this car before I bought 9398, so there 2 M-motors.
Now I'm building a rally offroader on L-motors with gear 3:5. This will be the successor to my old rally offroader - http://lego-tech.16m...lly-jeep-storaq

Edited by Sicil, 04 November 2012 - 08:43 AM.

[legomuppet9]

Your cars are so fast, keep up the good work

[TimH]

Very nice small and fast car.

[Sicil]

Thank you very much

[Tomik]

I like your car very much - it is small, fast and simple. I think I will try to build something similar...

[Tadej]

Nice car, maybe you would achieve the same performance with one L motor instead of two M motors.

[Sicil]

 Rally car Blacked.lxf 44.56K 60 downloads
I make instruction

[DLuders]

@ Sicil:  I liked your car so much, I built it from your original photos (before you created your LDD .lxf file).  "Imitation is the greatest form of flattery" -- thanks for sharing it!     See this Flickr photoset for detailed descriptions on the 16 pictures I took.  I had some problems "reverse-engineering" some things, so I came up with slightly different solutions than you did.  I did not have the same colored parts as you, so I used a red-and-yellow color scheme.



I added some parts to the front grille and underside of the hood (bonnet) to fill in the gaps.  The hood/bonnet pivots upwards; I used a temporary axle prop for the photo below.  The windscreen frame has been simplified.  Two white rally lights have been added to the roofline.  The car retains the original's "dog running" stance (where the rear axle is longer than the front axle).



I added a yellow brace under the rear window, a black rear spoiler, and a black rear bumper:



It is possible to replace your two Power Functions (PF) Medium motors with one PF Large motor (to save weight and increase speed a tad). The rear axle's gear ratio has been changed from 3:5 (0.6) to 1:3 (0.33) (by using a 36-tooth bevel gear instead of a 24-tooth bevel gear), since there was a lot of space above the axle. I had to "prop up" the PF battery box a bit so that it would not interfere wih that black 36-tooth gear (see photo above).Here you can see the single PF L-motor driving the solid white rear axle.  Additional photos of the L-motor's bracing is shown in the Flickr photoset.  Your car is now 45% faster than before!  





  

  

Edited by DLuders, 25 November 2012 - 01:56 PM.

[Sicil]

Ooo.... That's very cool.

Quote

The rear axle's gear ratio has been increased from 2:1 to 3:1 (by using a 36-tooth bevel gear instead of a 24-tooth bevel gear), since there was a lot of space above the axle.

You make a mistake.
The rear axle's gear ratio has been 3:5, not 2:1. Unfortunately, there is no way remake car, so I would like to see your video.

[DLuders]

@ Sicil:  Yes, you're right.  From Sariel's Gears Tutorial, "...a gear ratio is simply:
  number of follower’s gear teeth : number of driver’s gear teeth".  So, in the car I have, the gear ratio is 12:36, or 1:3.  I corrected my post above to read, "The rear axle's gear ratio has been changed from 3:5 (0.6) to 1:3 (0.33).... Your car is now 45% faster than before!"   [(0.33)-(0.6)] /0.6 = 0.45.

I'll make a video of it driving in a large room with 9V alkaline batteries, and post it here.

Edited by DLuders, 25 November 2012 - 02:05 PM.

[DLuders]

OK, here's a YouTube video showing Sicil's Lego Technic Rally Car "Blacked" with a 1:3 gear ratio:

[bmollema]

I like these 2 versions, I build it also a version and like driving around with it. 1 question are the wheels from the 8070 (I had clearance problems with the wheels....)?
I did not take pictures since it is not different form these 2. Thanks for the design....

[Tazmaniac]

What a great little car! well done, it'd be cool with-out rubber on the wheels (for drift action).
One tiny nit-pick , I think the doors should be rotated 180 degrees, I think it'd flow much better, but that's just me.
Top stuff.

[DLuders]

@ bmollema:  Both versions of Sicil's Rally Car "Blacked" use 41896 "Wheel 43.2mm D. x 26mm Technic Racing Small, 3 Pinholes"    .  They come in different colors, with these sets (not the 8070 Supercar).  Low-profile 41897 "Tire 56 x 28 ZR Street" are mounted on the wheels.  It should be noted that there is no room for a differential on the rear axle; only solid axles are used.

  

[Sicil]

DLuder, it's very fast and very cool, but unfortunately it isn't suitable for the rally, only for racing on flat surfaces. I didn't expect that my model will cause a lot of interest.

[DLuders]

@ Sicil:  Although a ultra-fast "Rally Car" may be difficult to drive using the basic Power Functions controller, one could use the 8879 / 64227  "Electric, Power Functions IR Speed Remote Control Unit with Dark Bluish Gray Base" unit for more precise control:

[DLuders]

@ Sicil:  When you built your original Rally Car "Blacked" MOC (with two Power Functions M-motors connected to a single terminal on the new v2 PF Receiver), did you happen to notice the phenomenon discussed in this TechnicBRICKS article by Conchas?  He summarized:

"The issue can be put shortly like this - When two or more Medium motors are connected to a single output of the V2 Receiver (no matter which one), they often make a squeaking sound instead of starting, and only start after some time, or if forced by hand. Even after they finally start and then stop, the problem occurs again."

Edited by DLuders, 28 November 2012 - 03:12 PM.