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Jato Tries to Define Rock Rey

As promised I violated my Venture and stole the Savox 2290 servo. I also assaulted my SCX10 II and stole the Mamba X ESC. The Mamba Monster X won't fit in the stock spot without cutting off the servo mount standoffs so I checked to see if the Mamba X will fit and it does. I contacted Robert from Castle to ensure the X was up to the task and he said it should be fine. So the Monster X will be saved for another build or maybe sold. It seems the Mamba X is plenty for the RCs that I have. I don't have 1/8th scale monster trucks, buggies or truggies.



I installed the Rock Rey servo horn from Exotek. I have to say this is the first time I installed a servo horn on a servo and it was in the correct location. I wouldn't need to use much trim at all! I was giddy, but I should have known it's never this easy.



The Exotek servo horn has a lot of meat around it for a clamping, or pinch, screw. This extra meat causes it to hit the aluminum servo mount. The Exotek instructions tell you to hack away some of the plastic on the stock mount. Since I went with the aluminum mount I'm not going to cut anything unless I absolutely have to.



Back to the drawing board. I ordered the Losi version of the aluminum servo horn for the Rock Rey. It does not have a clamping screw and appears to be much thinner. I'm hoping it clears the aluminum servo mount.

The drag link from the servo to bellcrank is freaking plastic. Another hokey engineering decision especially since it has a servo saver built into the bellcrank! WTF? If the Rock Rey had been designed after the acquisition of Axial I would blame them, but that happened after the Rock Rey so Losi is entirely to blame here. I will need to source rod ends and a link to beef up the drag link. I place an order last night on eBay and I also ordered some wires and stuff on RPP this morning. Now I wait as do you guys.
 
I've got the HR aluminum bell crank set up on my Baja Rey Jato. It has worked flawlessly and between that, the Savox servo upgrade and the aluminum upper and lower control arms, TLR turnbuckles, my steering and responsiveness improved night and day.

BTW - I saw you lubed up the trans gears. I totally get the logic, but I would highly recommend a dry lube. That thing gets more debris and particulate in it than you could ever imagine - even when doing the "seal" around the motor plate. I'm afraid a grease will simply attract even more.
 
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I've got the HR aluminum bell crank set up on my Baja Rey Jato. It has worked flawlessly and between that, the Savox servo upgrade and the aluminum upper and lower control arms, TLR turnbuckles, my steering and responsiveness improved night and day.

BTW - I saw you lubed up the trans gears. I totally get the logic, but I would highly recommend a dry lube. That thing gets more debris and particulate in it than you could ever imagine - even when doing the "seal" around the motor plate. I'm afraid a grease will simply attract even more.

I'm glad you had good luck with HR.

That thought crossed my mind more than once. But these are pretty beefy gears and I think they'll crush most particles that get inside the transmission. If I'm wrong I'll pay for it with a set of new gears. :mrgreen:

What lube did you use?

I had a few minutes last night to work on the RR. I decided to design and print a mount to hold the Mamba X ESC. I didn't want to cut off the stock mounting posts without at least trying to use them first.

I designed the bottom half of the mount in about 10 minutes or so and then fired up the printer. I was worried because I haven't even turned that thing on in maybe 6 months or more. Amazingly, the first print stuck and it was a success. Quality isn't that great because I was more interested in speed. And it fit like a glove!



Then I designed and printed the top. That worked nicely as well. Ah - success...nothing like it! "thumbsup"

Now I have a feeling this mount will interfere with the interior so it may go the way of the dodo bird. TBD



Then I installed the front bumper. The tiny screws going into the front of the bulkhead is a very odd choice. I don't understand it. It seems like they would pull right out of the plastic bulkhead, had I used stock, and now I'm kinda worried about them snapping off in the SSD bulkhead. I think those fears are unfounded though because the bumper is also held on with chunky screws on the bottom and something will go in the top of the bumper. The more that screws to the bulkhead, though, the more I'm glad I went with the aluminum SSD unit.



Now let's install the links on the rear axles. The more astute among you will notice I'm not following the manual step by step. Ohhhh I'm telling!

Jato, why you gots a paperclip hanging from dat there axle thangy? Well, after dropping the front pinion bearing out about 10 times while moving or just fondling and oogling the axle I decided it was time to keep it in before I lost it. I had paperclips handy and it worked like a charm! So, Pro Tip, use paperclips to keep your bearings from hiding!

Next to the VP axle you will see the stock, upper links that are included with the kit and the Losi aluminum trailing arm upgrades that I purchased separately.

I wanted JEC trailing arms, but he sold out like the day I decided to purchase them. They were in stock the day before, but they were the HEAVY SS version which is what I was leaning towards anyway. I contacted JEC and he said he'd get back to me. He never did. I find him to be very flaky at best. I even paid him money to make me a sway bar setup for my SMT10 and after months of not hearing anything I contacted him and asked for my money back.

We'll see how these Losi trailing arms hold up.



Unlike the rest of the links included with the kit, these upper links didn't have thread lock on them. I pulled them apart, added Loctite and started the tedious task of trying to get the link ends tight, but also in alignment.



Upper links, trailing arms, and driveshaft half have now found their permanent home on the VP axle. That's all until next time...

 
I have the Pro Modeler aluminum servo arm on my Bomber and Yeti. It's a very basic arm, but it gets the job done just fine. The only issue is that it's threaded for an M2 screw. I drilled and tapped the one on my Bomber for an M3. On my Yeti I drilled it large enough to pass an M3 through. Based on drilling 2 of them, they don't feel like that super soft junk that most aluminum arms are made of.

http://www.promodeler.com/PDRS201
 
I used Honda chain wax. Quieted the gear set way down, and does not seem to attract much, if any additional mess.
 
The bottom loaded motor is great for easy access to gear changes and such, but for day to day use I'm not a fan. You can see relatively large gaps around the motor cover. Those gaps, coupled with the foam, means I see a lot of dirt and water getting through these gaps and into the chassis and transmission. What were they thinking?

Would the T-Bone Delrin skid help keep the dirt out (assuming correct hole placement and subsequent installation)?

The front screw goes into the aluminum servo mount on the other side. This is a good thing and an added bonus of the aluminum servo mount.

Thanks for sharing this detail about the servo mount - along with other threads, helped me appreciate the structural role played by the servo mount. So I have an aluminum one on the way too!
 
I have the Pro Modeler aluminum servo arm on my Bomber and Yeti. It's a very basic arm, but it gets the job done just fine. The only issue is that it's threaded for an M2 screw. I drilled and tapped the one on my Bomber for an M3. On my Yeti I drilled it large enough to pass an M3 through. Based on drilling 2 of them, they don't feel like that super soft junk that most aluminum arms are made of.

- Arm, servo, 10-20mm #PDRS201

The Losi servo horn is even thinner around the servo splines. Odd that this photo from AMain shows a cracked arm. :ror:

los331007.jpg


I used Honda chain wax. Quieted the gear set way down, and does not seem to attract much, if any additional mess.

That's a good idea. I should have remembered that from my dirt riding days!

Would the T-Bone Delrin skid help keep the dirt out (assuming correct hole placement and subsequent installation)?

Thanks for sharing this detail about the servo mount - along with other threads, helped me appreciate the structural role played by the servo mount. So I have an aluminum one on the way too!

That's a good point! It just may help keep dirt out.

You're welcome! Always glad to help.
 
As promised I violated my Venture and stole the Savox 2290 servo. I also assaulted my SCX10 II and stole the Mamba X ESC. The Mamba Monster X won't fit in the stock spot without cutting off the servo mount standoffs so I checked to see if the Mamba X will fit and it does. I contacted Robert from Castle to ensure the X was up to the task and he said it should be fine. So the Monster X will be saved for another build or maybe sold. It seems the Mamba X is plenty for the RCs that I have. I don't have 1/8th scale monster trucks, buggies or truggies.



I installed the Rock Rey servo horn from Exotek. I have to say this is the first time I installed a servo horn on a servo and it was in the correct location. I wouldn't need to use much trim at all! I was giddy, but I should have known it's never this easy.



The Exotek servo horn has a lot of meat around it for a clamping, or pinch, screw. This extra meat causes it to hit the aluminum servo mount. The Exotek instructions tell you to hack away some of the plastic on the stock mount. Since I went with the aluminum mount I'm not going to cut anything unless I absolutely have to.



Back to the drawing board. I ordered the Losi version of the aluminum servo horn for the Rock Rey. It does not have a clamping screw and appears to be much thinner. I'm hoping it clears the aluminum servo mount.

The drag link from the servo to bellcrank is freaking plastic. Another hokey engineering decision especially since it has a servo saver built into the bellcrank! WTF? If the Rock Rey had been designed after the acquisition of Axial I would blame them, but that happened after the Rock Rey so Losi is entirely to blame here. I will need to source rod ends and a link to beef up the drag link. I place an order last night on eBay and I also ordered some wires and stuff on RPP this morning. Now I wait as do you guys.

Beautiful servo and thanks for the info about the Mamba X. I should have read your thread before posting a similar question on my thread. Didn’t think to ask Robert from Castle about pairings ...

Sent from my iPhone using Tapatalk Pro
 
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The 4mm bullet plugs and 12AWG wire came in so I soldered up the motor wires. This is about as clean as my wiring jobs get. Take it or leave it. I don't like how the sensor wire hangs at an odd angle though.



Some people tackle the difficult tasks first thing. Me? I'm a procrastinator - always have been. So, for me, this means shocks and paint come way towards the end.

Shocks...building them isn't bad, but bleeding them is messy and can be a royal PITA.

I bought Proline shocks and now, after thinking about it, I'm not sure why. These are go-fast shocks, excellent go-fast shocks, and I'm building a crawler. Oh well. Bad shocks never hurt and I can always make this Rock Rey a go-fast rig in the future. Or I can steal the shocks for other builds. But these are definitely my favorite shocks of the moment. I have some on a monster truck and they are just awesome.



I'm going with the official unofficial crawler default of 35 weight for the shocks. I like the little reg flag stickers that say "Add shock oil." They remind me of the FMF exhaust plug with the "Remove before flight" warning flag attached to it.



That was...to easy. Not even one swear word! What the **** happened? OK now just one swear word. :mrgreen:



The interior is nice. Detail enough for this kind of rig and it's pre-painted or molded in black (I didn't try to verify which). Awesome!



And I built the cage. This build was supposed to be finished today, but I'm awaiting a servo horn...a freaking servo horn! It's been showing as out for delivery since around 9AM and it's now nearly 6PM. Leaving soon to celebrate the birth of 2019 so this build will probably continue next year!

 
Now that the Christmas and New Year's rush is over, sadly, it's back to reality. But it also means I can get back to concentrating on this build.

Happy New Year you bad mama jamas!

Shortly after I posted my last post my servo horn was delivered. I usually get mail around noon and it's very, very rare for the mail to come late, but this time it was a little after 6 PM! :shock: I have no idea what was going on, but at least I got it.

Right here is the bastard that was holding up this build.



Here's the servo horn installed. But don't do like I did and put the ball stud on the wrong side of the servo. I quickly found this out when I tried to install the servo into the chassis. The ball should be facing down in this photo.



Here's the servo installed in the chassis. The manual calls for four (4) M3 x 14mm screws. I found that the two rear screws bottomed out inside the aluminum servo mount before the servo got tight. The front two screws hang through the mount, as you can see in the photo, so 14mm length is fine. The photo makes it appear that they are interfering with the servo horn, but that isn't the case. I had to source two M3 x 12mm screws for the back two holes.



Luckily Losi supplies this rarely seen "Extra hardware" bag. Awesome! "thumbsup" Inside this bag was one M3 x 12mm screw. I found another one that was included with this kit and I have no idea where it's supposed to go. But now it's going to help hold the servo in place.



The servo connects to the bellcrank with this plastic drag link. This is a pretty big oversight by Losi. No way this link survives much abuse on this chassis that is ultimately 1/8th scale. It's even dumber when you consider the fact that the bellcrank has a servo saver build into it.

I bought some Traxxas Revo rod ends to make my own link, but it turns out they are too large. I asked on Facebook, which often leads to a quick response like it did in this case, and was told to order Traxxas 2742X rod ends. So they are on order from eBay.

 
Now that the Christmas and New Year's rush is over, sadly, it's back to reality. But it also means I can get back to concentrating on this build.



Happy New Year you bad mama jamas!



Shortly after I posted my last post my servo horn was delivered. I usually get mail around noon and it's very, very rare for the mail to come late, but this time it was a little after 6 PM! :shock: I have no idea what was going on, but at least I got it.



Right here is the bastard that was holding up this build.







Here's the servo horn installed. But don't do like I did and put the ball stud on the wrong side of the servo. I quickly found this out when I tried to install the servo into the chassis. The ball should be facing down in this photo.







Here's the servo installed in the chassis. The manual calls for four (4) M3 x 14mm screws. I found that the two rear screws bottomed out inside the aluminum servo mount before the servo got tight. The front two screws hang through the mount, as you can see in the photo, so 14mm length is fine. The photo makes it appear that they are interfering with the servo horn, but that isn't the case. I had to source two M3 x 12mm screws for the back two holes.







Luckily Losi supplies this rarely seen "Extra hardware" bag. Awesome! "thumbsup" Inside this bag was one M3 x 12mm screw. I found another one that was included with this kit and I have no idea where it's supposed to go. But now it's going to help hold the servo in place.







The servo connects to the bellcrank with this plastic drag link. This is a pretty big oversight by Losi. No way this link survives much abuse on this chassis that is ultimately 1/8th scale. It's even dumber when you consider the fact that the bellcrank has a servo saver build into it.



I bought some Traxxas Revo rod ends to make my own link, but it turns out they are too large. I asked on Facebook, which often leads to a quick response like it did in this case, and was told to order Traxxas 2742X rod ends. So they are on order from eBay.





How do you like the servo horn? I’m trying to decide between the Losi and HR versions and they both look thin to me. What length link did you buy to replace the plastic drag link between the servo horn and the bellcrank? Thank you for the trailblazing, Jato, I’m definitely using the lessons you’re learning!

Oh, and for reference, Robert at Castle didn’t object to a Mamba X with a 3600 kV brushless in the Rock Rey - although I don’t mean to speak for him and he didn’t give a sign-off, just said it was likely ok.


Sent from my iPhone using Tapatalk Pro
 
How do you like the servo horn? I’m trying to decide between the Losi and HR versions and they both look thin to me. What length link did you buy to replace the plastic drag link between the servo horn and the bellcrank? Thank you for the trailblazing, Jato, I’m definitely using the lessons you’re learning!

Oh, and for reference, Robert at Castle didn’t object to a Mamba X with a 3600 kV brushless in the Rock Rey - although I don’t mean to speak for him and he didn’t give a sign-off, just said it was likely ok.


Sent from my iPhone using Tapatalk Pro

I'd go with the Losi version just because Hot Racing doesn't make the best horns in my experience. The servo horn has to be thin around the servo splines in order to clear the Losi aluminum servo mount. I can tell you that the Losi servo horn clears it just fine and works so I see no reason to not recommend it.

So far I only bought the rod ends to replace the drag link. I think I'm going to cut a piece of all-thread or a long screw to use as a link. I'll let you know what I do and pictures will surely follow after I receive the rod ends.

Thanks for the kind words! I'm watching your build as well.

I will say I think 3600kv is going to be fast!
 
Small update.

The Rock Rey has an interesting feature in that it captures the ESC's battery plug into the chassis. The problem is that it is only designed to hold EC3 connectors. I don't know of a single person that uses those stupid connectors. I use XT60 connectors and those won't fit into the EC3 holder. What do you do when need a part and you have a 3D printer? Well you design and print it of course.

Here it is hot off the press...err hot off the printer.



I like when a plan comes together. It seems to work well.




So now my ESC mount and battery plug mount are both 3D printed. So cool. 3D printers are awesome and every hobbyist should have one.

Now, again, we wait for parts...
 
Curious as to why you didn't print it with the holes for the screws? Worried about getting them aligned right?
 
Curious as to why you didn't print it with the holes for the screws? Worried about getting them aligned right?

I did design it with holes for the mounting screws. They are on the other side. I didn't realize the holes were supposed to be through all. :oops: A drill quickly made the blind holes into through holes. :mrgreen:
 
I did design it with holes for the mounting screws. They are on the other side. I didn't realize the holes were supposed to be through all. :oops: A drill quickly made the blind holes into through holes. :mrgreen:

Haha, that occurred to me after I posted.
 
I'd go with the Losi version just because Hot Racing doesn't make the best horns in my experience. The servo horn has to be thin around the servo splines in order to clear the Losi aluminum servo mount. I can tell you that the Losi servo horn clears it just fine and works so I see no reason to not recommend it.

So far I only bought the rod ends to replace the drag link. I think I'm going to cut a piece of all-thread or a long screw to use as a link. I'll let you know what I do and pictures will surely follow after I receive the rod ends.

Thanks for the kind words! I'm watching your build as well.

I will say I think 3600kv is going to be fast!


Thank you! I hope it’s fast and that it holds together!


Sent from my iPhone using Tapatalk Pro
 
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