[WIP] Greyhound - 4WD RC Buggy with BuWizz 2 - Redesigned wheel hubs

[agrof]

Is buildability against of this simple solution? I took 5M beam in order to give support in steered positions too.

[Didumos69]

1 hour ago, Lipko said:

Could you block the steering rods with the chassis instead? I know it would cause sum rubbing but maybe it would be acceptable. You could then replace the blue half-pins with a pin with pinhole and place a 180° axle connector between them with the center hole pointing upwards. I guess the movement of the rack is +- 1 stud, so the tiny edges wouldn't mean a problem. Or something like that... Or maybe the pin with a pinhole parts' pinholes should point upwards? You have some place in the chassis to fix their orientation.

Thanks! That's a good idea. The only thing is that this looses its blocking function for one steering rod in turns. Another thing I was affraid of is that the steering rods would trouble the steering rods too much in turns, as the hub ends of the steering rods move quite a lot forward in turns, but eventually this didn't turn out to be a problem at all.

41 minutes ago, agrof said:

Is buildability against of this simple solution? I took 5M beam in order to give support in steered positions too.

I tried something similar with a second pin with pinhole next to the one suggested by Lipko, but that did obstruct the steering rods in turns.

So this is what I did: Two pins with pinhole connected with a 3L pin (there is only one stud space between them) and two tow balls next to them.

And now it can climb a slope:

Thanks guys! Problem solved

[sirslayer]

wow, your creation climb up that ramp like it was going downhill!!! How come no one else have made a machine like yours?? Is there any special parts or custom made bricks.??? I think you may have redefined RC Lego standards and expectations!!  Three cheers to you!!!   

[ifilin]

Time to buy 2 Buwizzes? I've got 3 sbriks already. :)

Edited February 17, 2018 by ifilin

[Didumos69]

2 hours ago, sirslayer said:

wow, your creation climb up that ramp like it was going downhill!!! How come no one else have made a machine like yours?? Is there any special parts or custom made bricks.??? I think you may have redefined RC Lego standards and expectations!!  Three cheers to you!!!   

Thanks! A lot has to do with the BuWizzes that I'm using. And the fact that each motor drives a wheel directly. The hard part was to get the front axles strong enough to handle the power without getting a lot of toe-in. I pulled some tricks to reduce slack here and there, but nothing illegal and only LEGO pieces. I will show pictures tomorrow.

1 hour ago, ifilin said:

Time to buy 2 Buwizzes? I've got 3 sbriks already. :)

Yes you should! 

[Leonardo da Bricki]

That uphill... Incredible work. Cannot wait to more of this buggy! Speaking of which, mine is sitting around here somewhere...

[Didumos69]

9 hours ago, Leonardo da Bricki said:

That uphill... Incredible work. Cannot wait to more of this buggy! Speaking of which, mine is sitting around here somewhere...

Thanks! You mean your Nomad?

11 hours ago, Didumos69 said:

I pulled some tricks to reduce slack here and there, but nothing illegal and only LEGO pieces. I will show pictures tomorrow.

To put so much power to the front wheels only works if there is minimal slack in the front axles. Here are a few things I changed:

1.) The steering rods still had some play in them, because of the use of half pins and 2L axles that don't sit tight. So I used studded parts to connect the parts instead:

2.) The turn-table based wheel hubs work best (have the least slack) when the turn-table is integrated with pins rather than axles on each side of the turn-table. In the rear hubs I have that already, but for the font hubs I had to use axles on the chassis side of the turn-table. This gave some play between the turn-table and the chassis side of the hub. But with a belt wheel tire filling the space between the turn-table teeth and the chassis side of the hub, I could remove slack completely.

3.) The wheels are attached to the hubs with two axles sticking out of the hubs. Sofar I used 4L axles with end-stop and put half bushes and 3L levers (yellow) on them to prevent the wheels from sliding off. This worked quite well, but after a rough ride, I allways had to tighten these parts again. To solve this I used a trick with rubber connectors attached to the axles sticking out of the hubs, 5L axles with end-stop in.this case. The rubber connectors are squeezed to secure them to the axles. I have shared this trick before and was criticized that I could obtain the same with half bushes, but reality proves different: I made several rough rides with this trick installed and nothing needed to be tightened or readjusted. It simply works.

4.) Finally, I added some constructs to better square and reinforce the A-arms in the front axles. When the lower A-arms hit something, they got easily disconnected. And because the legs of each A-arm are wide apart, they didn't square well and introduced some sloppyness. So I added some constructs with crankshaft pieces that connect the legs of the A-arms. This squares the A-arms better and make them strong enough to absorb frontal impact without disconnecting.

Now it's time to take it outside again

Edited February 18, 2018 by Didumos69

[Leonardo da Bricki]

@Didumos69 Yes, I'll have an update on my Nomad in a day or two. Nice reinforcements using the system bricks, I have done that once or twice, it really works well.

[Didumos69]

This afternoon my kids and I had an outdoor RC buggy session . Kids with their toy RC buggy's and me with my Technic buggy. Here's a compilation of the video's we shot of my model. We shot video's of theirs too of course . My son did most of the filming (I had to beg him ) and even presented himself as 'live commentator' (Dutch only, sorry). The entire session passed without any problems or displacements in the build . Also the U-joints survived, thanks for the hint @nerdsforprez!

Edited February 18, 2018 by Didumos69

[agrof]

Nice and clean solution with the new steering links, like it! 

Also the performance is great, I am really curious what kind of bodywork will be dropped on. I suggest a rather minimalistic, easy to remove (modular) panel solution.

[nerdsforprez]

2 hours ago, Didumos69 said:

This afternoon my kids and I had an outdoor RC buggy session . Kids with their toy RC buggy's and me with my Technic buggy. Here's a compilation of the video's we shot of my model. We shot video's of theirs too of course . My son did most of the filming (I had to beg him ) and even presented himself as 'live commentator' (Dutch only, sorry). The entire session passed without any problems or displacements in the build . Also the U-joints survived, thanks for the hint @nerdsforprez!

glad the tip could be useful for such an awesome vehicle!

Edited February 18, 2018 by nerdsforprez

[u118224]

Just curious, what is the battery life on this? 

[AFOLegofan66]

Awesome video dude!!

[Didumos69]

15 hours ago, agrof said:

I am really curious what kind of bodywork will be dropped on. I suggest a rather minimalistic, easy to remove (modular) panel solution.

I will certainly try to keep it minimalistic. I will also skip things like a working steering wheel or a fake engine. I tend to see this build as a model of an RC buggy.

13 hours ago, u118224 said:

Just curious, what is the battery life on this? 

I don't know, actually. I only charged the BuWizzes twice since I have them installed (about 10 days ago) and I exercised alot (half an hour a day), but not always in ludicrous mode. Last time I charged them was last Saturday and they are certainly not empty yet.

13 hours ago, AFOLegofan66 said:

Awesome video dude!!

Thanks!

[Didumos69]

Now that the framework feels good enough, I thought I might share the LXF-file. Feel free to comment. Please note that this is still work in progress and please don't share it with others.

Edited February 21, 2018 by Didumos69

[Isamudyson]

the frame looks awesome. I can imagine a body similar to the rugged supercar on this.

[technic_addict]

Excellent torque and speed!  I am quite surprised at the performance thus far; hopefully the additional weight of a body won't impede its excellent performance.

Having built the Deadly nightshade and class1 by agrof, this actually may be the best one yet in terms of overall performance.  I haven't had time to change the class1 to buggy motors yet, so I don't know how that one performs.

 

 

[Didumos69]

23 hours ago, Isamudyson said:

the frame looks awesome. I can imagine a body similar to the rugged supercar on this.

Thanks!

22 hours ago, technic_addict said:

Excellent torque and speed!  I am quite surprised at the performance thus far; hopefully the additional weight of a body won't impede its excellent performance.

Having built the Deadly nightshade and class1 by agrof, this actually may be the best one yet in terms of overall performance.  I haven't had time to change the class1 to buggy motors yet, so I don't know how that one performs.

Thanks! I'm very happy with the power / speed balance it currently has. It can take a steep slope and ride an uneven surface with very acceptable speed. I will certainly do my best to make sure the performance won't be affected much by the additional weight of a body.

I'm thinking of naming it "Greyhound".

[Permo]

This thing is amazing !

Actually this build attracked me to eurobricks, solid engineering and high end performance, well done, chapeau !

Personally I want to stay away from software and computers as I find most joy in the freehand artistic hands on experience of building, but at this level I guess the software is really a usefull tool to work things out without breaking your fingers.

Edited February 26, 2018 by Permo
typo

[Didumos69]

Progress is slow, but I'm thinking of continuing the reuse of 42056 parts, which means an orange/black body. This is what I have sofar.

[Rudivdk]

Looks mean and clean.

[Alex Ilea]

Kinda looks like an insect ?

[Didumos69]

23 hours ago, Rudivdk said:

Looks mean and clean.

Thanks!

16 hours ago, IA creations said:

Kinda looks like an insect ?

Haha, yes it does. The 6L links sticking out will be part of the front window. I might also migrate to dark azure, which seems to be more trending anyway .

Edited March 8, 2018 by Didumos69

[Didumos69]

On 2/26/2018 at 1:30 PM, Permo said:

Personally I want to stay away from software and computers as I find most joy in the freehand artistic hands on experience of building, but at this level I guess the software is really a usefull tool to work things out without breaking your fingers.

For me using software speeds up the process. I can quickly check certain solutions I have in mind, much faster than when I would have to try every idea manually. But only after building it in real life I know for sure whether a solution works out fine or not. Also, when I change something digitally which makes a lot of sense, then I will never hesitate to actually do it, not even when it means I have to take the whole model apart again. For instance, recently I decided to move the lengthwise 5x7 frames at the heart of the main structure one stud forward to make space for an improved mounting point for the rear suspension arms. You can imagine I had to take everything apart to implement that.

[Permo]

Yes I see and I agree...

I like the hood with the black stripes, and I suggest to continue the black stripes over the rooftop and back of the car.

Still very impressed by the framework, don't hide all of it.