Jato Tries to Define Rock Rey

[furadi]

3000+ KV seems really high to me. These rigs are not designed to go fast. I run the 1512 2650kv castle motor and on 3s it's just kind of silly. Thing will not go in a straight line under hard acceleration.

[JatoTheRipper]

The kit shows that it's out for delivery today which is a day early! The parts from RPP are still on schedule for delivery tomorrow.

[mond]

Originally Posted by furadi

3000+ KV seems really high to me. These rigs are not designed to go fast. I run the 1512 2650kv castle motor and on 3s it's just kind of silly. Thing will not go in a straight line under hard acceleration.

I run the 2400kv on mine and it's pretty quick on 3S so geared it down allot. It's still super twitchy and needs the curve changed. The RR does do fast but would do properly fast if that rear diff could be unlocked.

[JatoTheRipper]

Well the USPS is screwing around and my parts from RPP and AsiaTees were delayed. So now I wait impatiently.

[JatoTheRipper]

Well, thankfully, my large order o' parts from RPP showed before the holiday. Look at dis goodness!



The first thing I wanted to tear into was the shiny, Vanquish Currie axle. Eye candy!

Let's weigh the housings.

Stock:


Vanquish:


Significant weight increase, but also a significant increase in strength and prettiness.

I didn't have much time to wrench last night and I wasn't in the picture taking mood so I didn't get many in between steps.

I did drill out the four holes in the ring gear so I could use the larger, Traxxas screws. It's the diff screw mod that all the cool kids are doing these days. And I can see why because the stock screws are not only course, but they are tiny - maybe 1.5mm to 2mm max in diameter. Too spindly for something that is, in all reality, an 1/8th scale rig. My only concern is that the screws end up being very close to the edge of the diff cup. I'm not sure how much of the plastic wall is left. We'll find out I guess.

My cheap ass drill bits had a tough time chewing through the hardened gear. I still have do to this mod to the center and front diff gears so those pictures will follow at some point.

Now, magically, onto the completed rear axle.

Damn, that is beautiful! The machining is great. The third member fits on perfectly. It's snug which is a good thing. And the internals are just as good. Everything fits perfectly and lines up where it should. Damn, I should have taken photos of the internals! I actually had to take it back apart because I added shims to both the ring gear and pinion. Plus, I forgot Loctite since I'm not used to aluminum axles.

Did you guys with the VP axles use both diff and pinion shims?

I used to be one of the most vocal Vanquish dectractors, but they have won me over. I'm a fan.



And the final weight on this assembled tank. 10.45 ounces...that's .65 pounds!

[Achilles Fender]

That Vanquish axle looks quality and the build looks like it will be super sweet!

I considered the same Vanquish axle but opted for the less expensive SSD third member for the moment for my Baja Rey. I'm little gun-shy about putting big dollars into the vehicle for two reasons.

1) It is my go-fast abuse vehicle
2) I am slightly concerned Losi will discontinue the Rey model line and I will be stuck with shelf jewelry if I break a part that is no longer available.

After reading about your experience drilling out the stock ring gear/diff cups I am wondering if I should try the Exotek aluminum diff cups. Anyone have experience with those?

[soze]

Saw the Super Rock Rey in person yesterday at the lhs. It's huge. Not sure where I'd be able to store or drive something like that.

[JatoTheRipper]

Originally Posted by Achilles Fender

That Vanquish axle looks quality and the build looks like it will be super sweet!

I considered the same Vanquish axle but opted for the less expensive SSD third member for the moment for my Baja Rey. I'm little gun-shy about putting big dollars into the vehicle for two reasons.

1) It is my go-fast abuse vehicle
2) I am slightly concerned Losi will discontinue the Rey model line and I will be stuck with shelf jewelry if I break a part that is no longer available.

After reading about your experience drilling out the stock ring gear/diff cups I am wondering if I should try the Exotek aluminum diff cups. Anyone have experience with those?

Mine will be a crawler with go-fast moments in between so much less abuse.

If you get the aluminum diff cups then you will have to drill and tap them out to use larger screws.

Originally Posted by soze

Saw the Super Rock Rey in person yesterday at the lhs. It's huge. Not sure where I'd be able to store or drive something like that.

I'm sure it is. I have a 1/5th scale HPI Baja and that is a beast. Even this Rock Rey looks like it's going to be huge. The axle dwarfs AR60 axles.

[Achilles Fender]

Originally Posted by JatoTheRipper

Mine will be a crawler with go-fast moments in between so much less abuse.

If you get the aluminum diff cups then you will have to drill and tap them out to use larger screws.

Part of the description for The Exotek Rock/Baja Rey Alloy Differential Gear Case on AMain's page says the following:

"The cup uses bigger than stock, steel screws to help prevent blowing out the gear diff under heavy loads. Screws require a quality 1.5 hobby grade hex wrench (do not use allen keys)."

Seems like it would be an easy drop-in upgrade to the stock diff cups if the screws are 2.5mm or larger.

[JatoTheRipper]

Originally Posted by Achilles Fender

Part of the description for The Exotek Rock/Baja Rey Alloy Differential Gear Case on AMain's page says the following:

"The cup uses bigger than stock, steel screws to help prevent blowing out the gear diff under heavy loads. Screws require a quality 1.5 hobby grade hex wrench (do not use allen keys)."

Seems like it would be an easy drop-in upgrade to the stock diff cups if the screws are 2.5mm or larger.

Oh very cool! I wonder what size screws they use. The Traxxas screws are 2.5mm. Good to know for the future if I have issues with the cups, but I don't foresee that.

Heavier cups does add rotational mass though so there is that drawback.

I emailed Exotek about the screw size. I will let you know what they say.

[JatoTheRipper]

Originally Posted by Achilles Fender

Part of the description for The Exotek Rock/Baja Rey Alloy Differential Gear Case on AMain's page says the following:

"The cup uses bigger than stock, steel screws to help prevent blowing out the gear diff under heavy loads. Screws require a quality 1.5 hobby grade hex wrench (do not use allen keys)."

Seems like it would be an easy drop-in upgrade to the stock diff cups if the screws are 2.5mm or larger.

Exotek got back to me already! Their diff cup comes with 2.5mm screws. Wish I had known this. They seem like a great upgrade.

[TheLetterJ]

I put the Exotek diff cup in my front diff a month or so ago... so far, so good! I've previously killed a couple gear sets (before aluminum front bulkheads were available), the stock diff cup, sheared the included screws in the HR TH aluminum diff cup, sheared the 12.9 screws in another HR TH diff cup, and I'm really hoping the M2.5 grade 12.9 screws solve my 'Rey's diff problems once and for all!

[Achilles Fender]

Nice! Good to know about the Exotek diff cups. I may just buy a couple since I'm going to be disassembling the front end and replacing the front bulkhead with the SSD bulkhead I have on hand now.

[JatoTheRipper]

Night 2 of wrenching.

First up is the SSD bulkhead diff housing. As always is the case with SSD products, it's pretty. This moron was working in light that was too dim for his old eyes and therefore he didn't see the single screw holding the bulkhead halves together. I was wondering why I couldn't pull it apart. Luckily I didn't use any force.



In a previous post I mentioned en-biggening the holes in the ring gears to install larger, mo-better diff screws. Here's a comparison of the Traxxas screw on the left (2.5mm, fine thread) to the stock screw on the left (2mm, coarse thread).

Dem lil' 2mm screwz iz two small for dat there darn 1/8th scale rig!



Ring gear holes enbiggened and mo-betta screws installed. As you can see the screws don't sit flash with the ring gear because the larger heads won't fit in the countersunk holes, but it doesn't cause any clearance issues like this.



Here's the diff installed in the SSD housing. I think it's crazy how the stock diff halves are held together by two, spindly screws and nuts, but the SSD housing only has 1 screw holding it together. I'm guessing other parts will hold the bulkhead halves together, but I guess I'll find out.



I'm used to removing plastic parts from sprues, which I haven't had to do for this build (Awesome!), but I did run into these odd, plastic barrels in some of the plastic parts.

The front suspension link mount has two of these plastic spacer barrels - one on either side. They have to be removed, but I just found them oddly interesting. It's something I've personally never seen with plastic parts.



I won't be using the stock part anyway as I purchased the Boom Racing piece. I choose Boom because it was cheaper that the Losi aluminum option part, it has an extra set of holes for more adjustability and it is black and looks much better than the clear anodized or grey aluminum. Boom Racing part on the left and stock on the right. The bottom two sets of holes are in the same location as the stock part with an additional row of holes above those.



Here is the Boom suspension link mount installed on the SSD bulkhead with the chassis top plate sandwiched in between.



In the photo above you can see the hinge pins captured on this side by tiny C-clips. These terrified me just looking at them. I was sure I'd lose at least one of them as it went shooting across the room at 100MPH. Thankfully, that didn't happen and they installed without much effort. But C-clips suck and these hinge pins should be captured in a more modern way with a plate or screws.

[JatoTheRipper]

In the photo above you will also see the driveshafts and suspension arms. The driveshafts and links actually come pre-assembled which is odd for an assembly kit. I was going to disassemble the driveshafts and put Loctite on the screws, but they must have done that at the factory because the screws were very snug so I decided to leave them as-is. Nice assembly which you don't always find from the factory.



More of the plastic "sprue" barrels in the knuckles. Yes, I am intrigued by them.



The front suspension arms are two-pieces and very sturdy. I would have preferred one, solid piece because I can see dirt and water getting under this cover, but they are nice regardless.

http://i.imgur.com/ORIhvXzh.jpg[/img]

Here are the front suspension arm assemblies with the very cool, very scale brake discs and calipers. You are just seeing these now, but they were the first things I assembled when I received my kit because the rest of the steps required aftermarket parts that had not yet arrived at that time. Don't hate me for hiding things from you, my adoring fans!



And here is the whole "front clip" assembly. The left side arm moves freely. It's exactly the way I'd want. The right side (your left) has a lot of stiction. I might disassemble it and sand down the arm to get it to move more freely.

In this photo you can also see the preassembled links which appear to be turnbuckles. That is a great thing! They were a little longer than the illustration in the manual, but I did not shorten them at this time.



Last thing for today is the center diff gear. This is much thicker than the front and rear ring gears. My cheap drill bits simply would not go through this hardened steel gear. Hopefully my LHS (Local Hardware Store) will have a hardened 3/32" drill bit so I can ream out these holes for the larger, Traxxas screws. To be continued...

[Jim85IROC]

Those front arms sure are an odd design. It seems like a normal, open 1-piece arm would have been cheaper to manufacture & assemble, lighter in weight, and just as strong.

[JDM74]

the Traxxas UDR arms are the same as are the Baja Rey's. Not sure why manufacturers have gone to this method.

[smog]

That's gonna be a hot lookin' rig Jato!

Couldnt agree with you more on the c-clips. They should be reserved for transmissions and shock pistons. There is nothing worse than having to search for a clip that has taken for a high velocity spit at some obtuse angle

[JatoTheRipper]

I'm still trying to decide on the paint color(s).

[smog]

Originally Posted by JatoTheRipper

I'm still trying to decide on the paint color(s).

Using Tamiya rattle cans?