Big Rock The Fat Rock

[Rottster]

OK, so chassis mods are complete for the 6s MMX and 1515 motor plus the gap for the spur to spit out pebbles and such.

 

[Rottster]

I took the front suspension off as an assembly and it makes reassembly much easier.

Don't forget your front suspension post screws! man, you'll hate life after the first jump, lol.
If you're just running 3s or don't run as hard as I do, you'll wreck your drive shafts. Just to keep things in perspective, I'm talking about the shafts that drive each wheel... That pin in plastic doesn't live for long. I found some aluminum ones that have put up with a ton of abuse, but they're not cheap (70 bucks a set) and they are heavy.... I lube them with 3m dry lube... so far, so good.

 

[Rottster]

The front steering is smooth as silk and almost zero play. The HR hubs and bellcrank really work well plus the titanium turnbuckles are a joy to work with, too bad they closed the shop. I should've bought another set to have on hand in case of a future tragedy, but they've been holding up just perfect so far as well as the team associated turnbuckle balls.

 

[RCbuzz]

This is such a great thread. It really embraces some of my favorite parts of the hobby!

Nice work, you are really testing/enhancing the 3S line's capabilities.

 

[Rottster]

This is such a great thread. It really embraces some of my favorite parts of the hobby!

Nice work, you are really testing/enhancing the 3S line's capabilities.

Thanks Brother, you seem more literate than most on here, are you from Europe or Asia?

 

[Rottster]

Well, this how you stuff a 1515 6s capable motor in a 3s Big Rock. You do it like this..

But where do you put the MMX6S?

 

[Rottster]

So, way, way one year eatler i made a custom MMX6s ESC mounting plate.... Looks like this...

Now, you all may understand the holes I drilled in the new chassis.
So what the heck is point of having a 250 buck ESC hanging on velcro! Yikes! So I made a bottom plate...

Bottom plate is counter sunk for FHCS, 14.9 grade and sandwiched double plane. Overkill... Yeah, buddy...
No better way to kill than over kill!

 

[Rottster]

So how you do this to fit the MMX6s in the Fat Rock?... But wait, how do I mount the servo? Is there room?

Is there room for a servo? Hmmm...... Maybe if I just cut the box, it drops right in.

 

[Rottster]

The answer is.... No, there is no room... Yes, there is. You can do it if you keep your drilling to a .5 mm tolerance. Same goes for the servo box.... You can, but can you? Everything on a Big Rock is so tight... I'm Sure someomne else found a easy way, this is just the way I did it.
The cut down servo/receiver box is installed... In stock configuration it's only held in by 3 screws, so.... It is what it is.

 

[Rottster]

Now the servo goes in... E-slay special, but so far I haven't destroyed it. The original puked pretty quick.

Almost ready for wire/receiver management!

 

[Rottster]

Ready to rock the Fat Rock! I'll steal the food scale in a moment, but ready to bust 80 on 6s. Everything is a very, very tight fit.

Ok, weight without wheels but with battery is...

 

[Rottster]

Ready to bust that 80 mph barrier.... Hopefully the weather holds out and the blacktop parking lot I use is nice and hot tomorrow for traction. With the 108mm diameter Hoons I should get about 88 mph according to my algorithm. I have softer tires, but they're 97 mm and I'd need to bump up to a 27 tooth pinion.

 

[Rottster]

Just in case I don't hit what I want, I have an idea....

This probably won't end well, but someone has to give it a shot. Calculated Top Speed is 133 or so, but I only have 1000 feet so.....