Streak Buggy with 3rd party parts (Video Finished!)

[JJ2]

Hello everyone,

   This is my newest creation, it is my forth MOC using non-Lego parts in its construction. I started this project when I bought some rear and front hubs from the Traxxas Rustler to try to fit them with Lego, it turns out that the rear hubs are almost exactly two studs wide and the front ones are about 1.5 studs. I also am using 2.2" wheels with the hubs, they are really grippy and are much better then Lego ones. Unlike my last MOC that had a full body with almost no gaps which ended up weighing about 1/4 the cars weight I went with a more simple design to save weight. 

IMG_1453 by JJ2Sam, on Flickr

IMG_1454 by JJ2Sam, on Flickr

It uses Traxxas 550 12T motor for drive, Hitec HS-322HD servo for steering, a hobbywing quicrun ESC 1060, a FLYSKY FS-GT3B remote, and a 7.2v 2000mah battery.

IMG_1455 by JJ2Sam, on Flickr

IMG_1457 by JJ2Sam, on Flickr

It has full independent suspension on the rear and the back but the back uses Lego dampening springs to stop it from bouncing around during high speeds.

Unlike my older MOC's this uses bearings for all of the drivechain components to stop friction, in fact without the motor mounted I could free-spin the wheels because of the low friction. With no surface to rub against no parts were damaged on the drivechain except early versions of the parts to adapt the Traxxas universal joint to Lego.

IMG_1467 by JJ2Sam, on Flickr

IMG_1468 by JJ2Sam, on Flickr

The total drive ratio is 9:1 with the 12T gear on the motor going to a 36T that goes to another 12T to the 36T differential, this gives it a lot of torque and acceleration.

When I designed the chassis I wanted to place the heavy components as low as possible and the motor ended up the same level as the bottom plate with the battery just 1 stud above it. Because of this I can turn at high speeds an it no flip over, there were a few times I would hit a large bump or rock in the road and it would simply skid around not flip.

 IMG_1458 by JJ2Sam, on Flickr

IMG_1459 by JJ2Sam, on Flickr

The steering on this is much better then my last ones and has a pretty good radios for its size, I am using a rack and pinion setup with turnbuckle steering links that allow me to adjust the toe-in or out, I set it to have a small amount of toe-in and with that it can stay going strait for a long time at high speeds.

I have used a GPS app on my phone and it says the top speed is 24.9mph or 40kph

 

Edited April 13, 2017 by JJ2

[Sylvian]

interesting,.. Defenitely not for the purists,. Must be a blast to drive though!

Funny, i ordered a Tamiya Pajero cc01 a week ago.. bcuz everytime i build a lego chassis it has me like 'meh' peformance wise. 

 

[Attika]

Ohh, why are you tempting me? I don't wanna do this, I don't wanna do this....  Those susp arms look so much more fit for the purpose... 

[Rooneypower]

Looks sweet i really like why you are going with this build! I always enjoy seeing lego used outside the box great work!

[z3_2drive]

Another great project, glad to see it turned out successful. I only have two questions, the screws holding the front wishbones to the chassis, they screw directly into Lego pins? Seems quite snug. My second question is what size bearings did you use? Do they just fit between a width of two studs? I know you have a 3D printed differential frame piece that can hold bearings, but what about the other parts of the drivetrain, how are they braced if you use bearings on every contact point?

[JJ2]

14 hours ago, Sylvian said:

interesting,.. Definitely not for the purists,. Must be a blast to drive though!

Funny, i ordered a Tamiya Pajero cc01 a week ago.. bcuz every time i build a Lego chassis it has me like 'meh' performance wise.

Thanks, that's exactly why I am using 3rd party parts, I was sick of putting a lot of time into a build for it to be sluggish when driving

14 hours ago, Attika said:

Ohh, why are you tempting me? I don't wanna do this, I don't wanna do this....  Those susp arms look so much more fit for the purpose... 

You don't know the power of the dark side

8 hours ago, z3_2drive said:

Another great project, glad to see it turned out successful. I only have two questions, the screws holding the front wishbones to the chassis, they screw directly into Lego pins? Seems quite snug. My second question is what size bearings did you use? Do they just fit between a width of two studs? I know you have a 3D printed differential frame piece that can hold bearings, but what about the other parts of the drivetrain, how are they braced if you use bearings on every contact point?

The screws go through some pins with studs with the stud cut off and it is a nice fit, there is some play though. The pins are exactly the same size and the inside of Lego pins so the fit really good. The bearings are 3/16x3/8x1/8" size, the motor has the gear on it going to a 36T gear mounted on my bearing 5x7 frame that goes to the two differentials outputs that are also on bearings that then go to the hubs which also have bearings. The model totals 14 total bearings, 8 for the 4 wheels (2-per wheel) and 6 for the differential brace.

My next project will use these https://www.shapeways.com/product/B9JJB2UAP/bearing-mount-3lx3l?optionId=61981868&key=19385873447ca56a6028d59c7088ed70&li=shop-inventory

[z3_2drive]

Ok, so there is only one reduction before the differential. Is the gear on the motor a plastic Lego gear (12t double-bevel), or metal with unique tooth count? And the gear driving the differential is a plastic 12t? or some custom stronger piece? One more thing , are those 'shocks' on the front fluid filled or just sprung? I can't wait to see the video, I'm trying to absorb as much detail as I can because I want to attempt a similar project 

[JJ2]

7 hours ago, z3_2drive said:

Ok, so there is only one reduction before the differential. Is the gear on the motor a plastic Lego gear (12t double-bevel), or metal with unique tooth count? And the gear driving the differential is a plastic 12t? or some custom stronger piece? One more thing , are those 'shocks' on the front fluid filled or just sprung? I can't wait to see the video, I'm trying to absorb as much detail as I can because I want to attempt a similar project 

The gear on the motor is a plastic double-bevel 12T from Lego, it has held up marvelously and does not show any type of wear, I put grease on it every once and I while to keep it running smoothly. On the original prototype the gear driving the diff was a Lego 12T and since they are so weak they ended up breaking every 5mins so I went to a cad program and designed this, I have it in plastic because I'm not sure if metal printing tolerances are good enough for a small gear, but I have done doughnuts with the car and it has worked perfectly. The shocks on the front are actually from a cheap toy-grade RC car from a garage sale that I picked up, they are not fluid filled so still bounce around a lot.

[Lox Lego]

Awww man!! Cool build. I'd really like to build an offroader like this in the future. 

[JJ2]

On 4/11/2017 at 9:21 AM, Lox Lego said:

Awww man!! Cool build. I'd really like to build an offroader like this in the future. 

Thanks

The video is finished

 

[mocbuild101]

COOL! , this is similar to what I was thinking of making when my cheap WLToys buggy breaks (which I know it will!).

[Attika]

That part when it is drifting in the dust is really badass  Cool. I've just realized from the street view that I've seen some of your crazy motorised sets before but didn't connect the dots. All deserves a 

[Boxerlego]

Excellent Work, Look at that buggy fly. Nice job on building the Hybrid RC. It's interesting to so see how much you put into this, But once you start looking at everything that is involved your pretty much building a Lego chassis around standard RC parts along with some 3D Printed parts here and there to make it work. Its Interesting to watch but I see the perception deception when it  come to builds like this sure you want to build a RC car out of LEGO but the question still remains how much Lego will you need to Sacrifice to get the performance that you desire in the RC Buggy.

[PorkyMonster]

I'm no purist for sure, but I have mixed feelings .

I agree with @Boxerlego in that in the end, are we going to end up with just Lego body/shell, and everything else 3rd party? Replacing the PF components is one thing, but replacing other pure Lego parts like suspension arms and differential would be quite a different thing altogether.

Perhaps it'll be more fun for us to take this as a baseline, and endeavor to build our future models with LESS non-Lego parts while retaining or even improving on performance .

PS. Perhaps I'm a HALF-BAKED PURIST

[JJ2]

11 hours ago, mocbuild101 said:

COOL! , this is similar to what I was thinking of making when my cheap WLToys buggy breaks (which I know it will!).

I look forward to seeing it

11 hours ago, Attika said:

That part when it is drifting in the dust is really badass  Cool. I've just realized from the street view that I've seen some of your crazy motorised sets before but didn't connect the dots. All deserves a 

Drifting in the dust was really fun, If you have a smooth surface like cement and its a little dirty you can drift everywhere.

6 hours ago, Boxerlego said:

Excellent Work, Look at that buggy fly. Nice job on building the Hybrid RC. It's interesting to so see how much you put into this, But once you start looking at everything that is involved your pretty much building a Lego chassis around standard RC parts along with some 3D Printed parts here and there to make it work. Its Interesting to watch but I see the perception deception when it come to builds like this sure you want to build a RC car out of LEGO but the question still remains how much Lego will you need to Sacrifice to get the performance that you desire in the RC Buggy.

I agree with what your saying, there is a lot of non-Lego in this, I think this is the limit of how much RC I will be using in Lego build's I think any more would feel like I'm building a lego body for a RC car.

10 minutes ago, PorkyMonster said:

I'm no purist for sure, but I have mixed feelings .

I agree with @Boxerlego in that in the end, are we going to end up with just Lego body/shell, and everything else 3rd party? Replacing the PF components is one thing, but replacing other pure Lego parts like suspension arms and differential would be quite a different thing altogether.

Perhaps it'll be more fun for us to take this as a baseline, and endeavor to build our future models with LESS non-Lego parts while retaining or even improving on performance .

PS. Perhaps I'm a HALF-BAKED PURIST

The reason I used non-Lego suspension arms is because the top links are about 6 1/2 studds long or more and the 1/2 stud meant I would have to make a very sturdy suspension are with a half stud offset and I could not figure out how to do that at that time so I just went with it, I am not happy with the front suspension arms either, they had slack in the way I mounted them which meant it would deform making the car drift left or right.

I plan for my next build to only contain bearings and a few printed parts (Like bearing holders) , and most likely a PF battery box.