I present to you my next creation.
 It is one of the most popular Tatras, especially popular among LEGO builders, 813 series in the basic military version 8x8 Kolos 
(Kolos is the code name of the project under which the 813 series was originally created as an artillery tractor for the Czechoslovak Army) 
supplemented by a BZD-T 813 dozer blade. Model is powered by 4 PF L motors, steered by 1 PF servomotor, the blade is controlled by one PF M motor. 
The cannon in one of the photos is a Czechoslovak anti-aircraft gun PLK 57mm Čs.

 

Nice idea to increase the wheel size, I would like to see the best part for me, the steering and drive train.

I have been using this method of wheel enlargement for a long time because there are only a few LEGO wheels that would fit proportionally,
if I do not want to change scale of the model, or rather no such LEGO wheels.
But in the future I plan to buy tires for this model that could eliminate this problem,
I will put a link to them here. Unfortunately, this model has been disassembled for several months,
but I'll try to give you some better photos of the chassis.

Tires: (compatible with 43x26 LEGO rims)

https://www.thicon-models.com/thicon-1_14/felgen-und-reifen/1_14-reifen-gelaende-mit-einlagen-schmal-paar

 

I'm adding a version with a two-door cab

 

Edited May 5, 20204 yr by Tatrovak

Nice thank you, from my purist view I preffer your wheels over third party wheels.

 

I understand your purist view of things, by the way, I'm adding a link to my Yotube where is a short demonstration of the driving characteristics of this Tatra

 

 

 

 

A small update to my Tatra 813, now as a ISO 1C container carrier. For drive is now used six PF L motors instead of four as in the previous versions.

 

Edited December 30, 20204 yr by Tatrovak

Very nice work! That tire enlargment with treads - does it not slip?

The custom tires look nice but don't fit that good as it seems.

Thank you MajklSpajkl, if you mean sliping of the tires against the discs, the they are glued together with melting glue. And if you think that the tires do not fit to desing side, then you are unfortunately right, but i have not been able to get anything better then that so far. These would rather be suitable for the 815-7 series.

Edited December 31, 20204 yr by Tatrovak

After a long time, I am adding here an update of my Tatra 813, all this time I have been returning to the construction of Tatra 813 again and again (Because the construction of 813 is the reason why I actually assemble LEGO TECHNIC and it is something like the holy grail for me) and I think that I can modesty and with a clear conscience to say that I have made progress.
One of the catalysts of this progress was the tires (if anyone is interested, they are Fischertechnik tractor tire 80), they were always a problem for me when building Tatra 813, since LEGO does not offer any that would fit proportionally, I experimented for a while with the tires from set 42129 but in the end I also rejected them because of the width. I've had these tires from Fischertechnik at home for almost a year, but it took me a long time to adjust the size of the entire model so that it fits the tires. The drive train consists of six PF L motors that are coupled 1:1 with the drive shaft, so that the only reduction in engine speed is provided by the L-gearing of the differentials and the planetary reductions, and in this configuration it works with 100 percent reliability. The steering is rack-and-pinion controlled by one PF servomotor (or its Chinese replacement). One PF M motor drives the winch and one PF M motor controls the dozer blade. It is designed so that it can be disconnected and connected as easily as possible, it is held on four pins through the middle of which passes the drive shaft that leads the torque from the engine to the blade, and the drive motor remains inside the Tatra even after the blade is disconnected. I also tried to work on the design of the cabin to make it look as realistic as possible, perhaps the use of parts in DBG color also helped, but olive green would be ideal.

 

Looks very nice and detailed!

I think the studless DBG gives it a nice gritty aesthetic

Thank you for the compliment

Have you tried to fit the new tires from the 42160 to it? :-)

no, I don't have them, but anyway, they don't fit on the Tatra 813 in terms of design.

Nice model, it looks good with those tires. As far as I understand, the width difference between 81mm Lego tractor tires and FisherTechnic tires is very important here not just aesthetically but also clearance-wise; the FisherTechnic ones being a bit slimmer allow the longer steering arm to clear. This is a pain point with 81mm Lego tractor tires, some larger steering arms/linkages don't work with it, which is a pity as they are less useful with actual off-roaders. Luckily they work better with Audi tires, though their thread pattern is less aggressive.

@Tatrovak, do you know a way to purchase those FisherTechnic tires separately?

13 minutes ago, Jundis said:

Have you tried to fit the new tires from the 42160 to it? :-)

Those should fit in terms of clearance, but agreed that design-wise not so much.

As for the clearance between the tires and the rest of the model, that is a problem that can be solved, even with certain compromises, the design side of things is worse, from the profile view the 81mm tires from LEGO looked good, but for example when viewed from the front it was evident that the tires are too wide, and it just looked bad.

 

As you can see in the first of these videos, I have completed my Tatra 813 in the trailer tractor version with a double cabin (this is the basic model of the Tatra 813 and all other versions are based on this one, and I tend to assemble my 813s accordingly, whenever I improve something first I will build this version, or better said at least a four-door cab and then derive a two-door cab version from it). I subsequently converted it again into an ISO 1C container carrier from the PMP-79 set (field mechanized laundry model 1979).
 

 

 

Hello Tetrovak! I become here from Youtube for private messages 

I wrote you a private message