My first Trial Truck with 94mm wheels. Features drive, steering, fake engine and independent suspensions with swinging half-axles. Including building instructions.
The aim of this truck was to participated at the contest organized by Freelug at Fana’briques 2010. The main impositions were : powerful, high ground clearance, small turning radius and full independent suspensions. In order to complete the challenge, I have ordered 2 94mm-diameter wheels,then the building process could start. The axle are the most resistant tatra’s axles I have made, because I used this parts to create the bevel gears, reinforced by transverse liftarms to lock the structure. The 94mm-diameter wheels enable to use portal axles with high ground clearance. The final reduction is 12/20, 8/24, 8/24 so 1/15.
In order to have the maximum of stability on slope, I have chosen during the building process that the Battery Box will be in the frame, in the front for 66/33 wheight distribution. As far as I know, the 66/33 weight distribution is very good for clearing abilities with real off-roader vehicles (you can consult this post to understand why). To avoid a complex drive-train to give power on the fake engine, I used a simple drive-shaft as real, built with 2 U-joins. Considering the small place I had near the XL motor, I have chosen to build the U-join with a Ribbed Hose as suggested on the official lego patent.
The steering is operated by a M-motor hidden in the cab, It drives 2 pulley with Rubber Belts, before the 8t/rack pinion. The turning radius is 50cm, that is quite good considering the scale. The real Tatra has a turning radius of 7.5m (15m to 180° turning), with 1/12 scale, the corresponding turning radius I have is 6m, that is really good. To conclude with the clearing abilities, they are really good, much better than my unimog (V2), thanks to the wheels, the ground clearance and the turning radius. The suspensions work great but this type of axles generates a little friction on the bearing axles, that is why it still could be improved. Fortunately, it’s the main purpose of the quest of “holy trial truck”. Nota : on the video the battery box is really tired. You can watch the building instructions here.
Another Youtube’s videos by a member : http://www.youtube.com/watch?v=UYhvfea9Y8s by Legoman104
The building instructions are available. You can watch them by browsing my website or
Download the Zip Archive of the Tatra 4×4’s instructions, 7 mo, ZIP.
Designed in 2010
January 6th, 2013 on 11 h 12 min
Many thanks for your contribution ! Regards.
January 4th, 2013 on 7 h 17 min
I have created this truck in Lego Digital Designer and posted it to my webpage. It will generate a parts list and more detailed instructions.
http://dndbricks.com/digitaldesign.html
January 3rd, 2013 on 2 h 41 min
hi nico! my name is autin fretschel. i love to build lego trial trucks but there are no races ina merica. another thing is that i am building a lego tatra. i need some help with the winch and back bed. thanks
December 6th, 2012 on 20 h 13 min
Sorry, no, this steering is accurate and reliable, what we expected of a Trial Truck steering.
December 3rd, 2012 on 0 h 42 min
could you make a better version of the suspension.
February 18th, 2012 on 15 h 59 min
i’m your fun but in this model the sterring don’t function very well can you help me with this problem? thanks
February 18th, 2012 on 15 h 56 min
really tank for this chassis, I don’t used power+functions but I have used rc unit with old 9v motor from the set 8475 and I add another rc motor…now it’s a very beast
January 30th, 2012 on 23 h 48 min
hellow i am a big fan of your models can you make more detailed with these instructions
Thank You
Devon
December 28th, 2011 on 12 h 19 min
Bien sur, pas de problème / Of course, no problem.
December 27th, 2011 on 14 h 50 min
excuse-moi nico, mes es-que ce serais possible que je prend ta cabine de tatra ? je veux en faire une mais je peux pas réussir.
December 21st, 2011 on 6 h 27 min
I was in the process of building this truck and I tested it when the drive and steering where completed and the differentials crack, I use the small universal joints that Lego has made and I added some parts to make the axles more strong. Can you help?
October 8th, 2011 on 13 h 21 min
and good luck whith your next model i hope it goes well and i hope you put instrucs for it.
October 8th, 2011 on 13 h 20 min
right ok but i have never used it in sand,mud or water.
i guess its just i dont build things good enouth to make them exellant but but i have used it alot and in alot of stress and once overheated so it mussed be that.
October 6th, 2011 on 18 h 29 min
Hello, I don’t think that XL become used after 2 years. Maybe do you have used your motor in agressive environment (dust, rust, sand) ? So you motor should have the same power even if they are two-year old. I hope I have respond correctly. Regards
October 6th, 2011 on 12 h 58 min
hello nicolas but i have a big question when XL motors get old,do they also get weaker? i have had mine for about 2 years now,would it still have the same power as it used to? thanks if you reply correctly.
July 8th, 2011 on 13 h 21 min
This is a great lego replica of a tatra 4×4.
June 23rd, 2011 on 10 h 09 min
I think it is possible. But, I know that the steering is not perfect, les pulleys slip. Regards
June 23rd, 2011 on 6 h 46 min
Hi Nico,
I have just finished this Truck, thanks for the instruction photos! This vechicle looks great, I love the design and the suspension as well. Do you think it’s possible to make the driving system with knob wheels? Because the 12 tooth bevel gears and 20 tooth gears easily slipping in case of high torque.
Thank you,
Peter
May 21st, 2011 on 18 h 10 min
Sorry, I don’t have enought part to sell one copy and keep my own parts. You can go to bricklink.com and purchase all you need, then follow the building instruction and you will have your copy of my tatra ! Regards
May 21st, 2011 on 17 h 44 min
hi, i was wondering if it would be possible to get one built for myself, as i don’t have the access to the types of parts that are need. i don’t need it to be motorized, as its going to be on my work bench and such for display. I’m a huge fan of Tatra’s. I’m willing to pay a reasonable amount if need for parts(including mailing and such)
thank you.
April 15th, 2011 on 14 h 57 min
Hi,
I build up this amazing model, great job!
Have one concern regarding steering, compare to Unimog V3 steering it is too weak and too fast, did you somehow enhance it?
I will try to reduce the M motor RPM and will see if it work.
Again Great work and thank you for sharing your ideas.
Marek
March 4th, 2011 on 23 h 31 min
You can check the Instructions folder on brickshelf to watch all pictures you need.
February 28th, 2011 on 19 h 49 min
If you could make more detailed photos or even building instructions for the basic tatra type chassis that is included in this trucks folder on brickshelf, it would be great
February 17th, 2011 on 11 h 52 min
Yes you can. Regards
February 14th, 2011 on 2 h 31 min
i dont have that ball joint can i use the normal gray one instead in the steering
December 20th, 2010 on 22 h 26 min
grüße nico
gibt es für deinen tatra einen plan würde ihn gerne mal nachbauen
mfg manuel
December 18th, 2010 on 21 h 48 min
This is a very amazing model I finally got most of mine put together with a few substitutions for some of the lifts arms for the truck my only question is how do you keep the drive pulley for the steering from sliding out of the motor did a few test drives an it keeps slipping out.
November 28th, 2010 on 11 h 31 min
Check the post to see the link to the building instructions. Regards
November 20th, 2010 on 17 h 38 min
Wow, realy amazing!
i like the steering, thats not easy!
Good Job!
November 15th, 2010 on 20 h 07 min
I was wondering if it be possible to give a list of which elements an how many were used in this model.