Building my JKU for Brushless Power

[k7zpj]

I am helping a couple friends with building the JKU kit and decided to get one to build along with them. To add something new and more interesting for me, I decided to go with a brushless motor. Since I try to give my rigs more rock time than shelf time, this build is going to be more about hardening the drive train for brushless power than adding lots of eye candy to the jeep. I am also trying to incorporate the experience I have gained by breaking parts on my Honcho and Wraith. This build will probably be slow one since I don't want to get too far ahead of the people I am helping. I will be updating as I make progress.

Here is the parts list.
Kit: AX90027 2012 Jeep Wrangler Unlimited Rubicon

Electronics:
Tekin ROC 412 2300 kV Crawler Motor
Castle Creations Mamba Max Pro
Hitec HS7954SH servo
CC BEC 10A
HeyOk Brake light Controller -- HeyOK's RC Electronics items (all in one place)

Front Axle:
Axial HD Bevel Gear Set 36T/14T AX30401 (Over Drive)
Vanquish Products Full floating heavy duty locker
Vanquish Products VVD Heavy Duty Axle Shafts
STRC Precision CNC Machined Aluminum Steering Knuckles
STRC Precision CNC Machined Aluminum Hub Carriers
Axial Aluminum Servo Horn 24T (Hard Anodized) AX30835 --
Axial SCX10 TR Links Parts Tree AX80043 (4-link Truss)


Rear Axle:
Axial HD Bevel Gear Set 38T/13T AX30395 (Stock) -
Vanquish Products Full floating heavy duty locker

Transmission:
Supershafty AX10 "ULTIMATE" Motor Plate -- Supershafty AX10 "ULTIMATE" Motor Plate
Supershafty WRAITH & AX-10 BEEFY Top Shaft -- WRAITH & AX-10 BEEFY Top Shaft - Super Shafty
Vanquish Products Axial AX-10 CNC Machined Aluminum Transmision Housing
ROBINSON RACING PRODUCTS #1540 AX10 Scorpion Hardened Aluminum Machined Locker Diff. Gear
ROBINSON RACING PRODUCTS #1541 AX10 Scorpion Hardened Steel Idler Gear
ROBINSON RACING PRODUCTS #7856 Traxxas Slash 2WD High Performance GEN3 Slipper Unit

Chassis and Suspension:
R2J Kustoms Stainless Steel Link Kits for SCX-10 -- http://www.rccrawler.com/forum/chass...-scx-10-a.html

Body:
DinkyRc JK HeadN'Tail Light Kit JK HeadN'Tail Light Kit


The parts are on order and the delivery truck is dropping parts off almost daily.


The kit has come in and I have opened it to take a peek.


Now I have to wait until more of the parts arrive and hope that not too many get lost in the mail. Updates to follow as the build progresses.

[cazper51]

Very cool. Can't wait to see it come together.

[k7zpj]

Most of the parts have arrived. Here is the mandatory “bling pile” snapshot.



Let the build begin.


1: The parts for the front axle make a up a good share of the bling pile.
2: I have decided to use the overdrive gear set for the front axle along with VP lockers.
3: The o-rings go on the inner part of the lock to allow some movement to help protect the axles bearings.
4: Inner and outer locker parts.





5: The inner part of the locker needs to be positioned so that the set screws line up with the holes in the outer part of the locker
6&7: These are the side views of the locker attached to the bevel gear.
8: You can see that the set screws are accessible through the hole in the locker.






9: I decided to try out the VP VVD front axle shafts to see if they are more resistant to breaking pins and axle stubs than the Axial Universal shafts.
10: Here is one of the VVDs disassembled before putting a light coat of grease per the instructions.
11: This shows the VVDs and locker placed in the axle housing. The set screws for the locker need to be tightened down after the C-HUBs and knuckles have been installed. On the Wraith this is easy since there is a removable diff cover. With the SCX10 you need to drill two 4mm holes in the axle housing and then plug the holes with set screws. Since the use of the set screws is optional and that there is almost no slop without the set screws, I decide not to use the set screws.
12 : Due to not having an unlimited budget for the build, I decide to use STRC C-HUBS and Knuckles which fall into the mid-range of cost and quality.




13: The VP VVDs are larger in diameter than the Axial universals which reduces the clearance between the Axle joint and the C-HUB. I checked the clearance between the VVD and the C-HUB to be 0.4mm.
14: The fit of the STRC knuckles is as good as the Axial aluminum knuckles. The bearings fit in snugly but are not overly tight and they can be removed without too much pressure.
15: With the flange pipe bushings installed there is no slop between the knuckles and C-HUBS. You need to check to make sure that the screws attaching the knuckles to the C-HUBS don’t extend through the C-HUB and cause the VVD to bind up.
16: The front axle is together now and I have added the 4-link truss from the AX80043 Axial SCX10 TR Links Parts Tree.





17&18: Not as many option parts for the rear axle. Just the VP locker and the Axial HD Stock gear set. I decided to run stock in the rear based. I have over/under on my Wraith and I am seeing the rear wheels hopping when running on dirt trails at higher speeds. I will give the stock gears a try for a while to see how they run.
19: The tang on the stock axle shafts are not long enough to full engage with the locker’s set screw. The red line indicates how much longer the axle needs to be able to use the set screw. The tolerances of the locker are tight enough that there isn’t much slop even without the set screw. The upside to this is that you don’t need to drill the holes in the axle housing for the set screw access.
20: The rear axle is now all together and I can move on to the drive shafts.

[k7zpj]

The WB8 Wild Boar 8 drive shafts are a big improvement over the original Ax10/Scx10 drive shafts. However the hollow plastic drive shaft has the problem of crushing and twisting if in a bind under a lot of power. A common mod is to thread in a 6mm bolt in the drive shaft to keep it from crushing. Works great but getting the bolt out can be a major pain if you need to repair the shaft’s joints.
This mod uses an old Honcho link instead of a bolt so that you can insert a cap screw into the link to put the link out of the drive shaft when you need to remove the joint or replace the shaft.


Picture 1
1) The WB8 drive shaft is hollow. The inside diameter of the drive shaft is 5.8mm which slightly smaller than the 6mm Axial links.
2) I used an old 6mm x 106mm Honcho link. I sanded the link to remove the coating and to reduce the outside diameter so that the link can be inserted in the drive shaft without expanding it and so that it can be remove. Be careful not to sand too much off since the link needs to fit tight in the drive shaft.
3) I inserted the sanded link into the drive shaft and marked it so that I could cut it off flush. When trimming for the second shaft make you don’t trim off the treaded end.
4) The length of the trimmed links was 45.2mm. A 6mmx91mm link is the perfect size to mod both drive shafts.








Picture 2
1) Here is the inner drive shaft with the link inserted into it. The shaft won’t crush and bend with the link in it.
2) To remove the link, thread a cap screw into the link and give a pull with a pair of pliers.
3) I have completed the mods to both drive shafts and I am ready to proceed with the next steps.

[buddamonk]

Cant wait to see more...i was thinking about getting a 2nd JK kit and put wraith axles on with a brushless setup to mod it up to a JK rock racer...here is my current JK

[cox308]

Awesome start and I really like how you're making this thread. Very well thought out.

I have the same motor/esc combo. You will need 32 pitch pinion and spur and you'll probably be needing metal driveshafts shortly.

Looking forward to seeing how you like it once its up and running.

If you're going to stick with the plastics axle housing's I'd highly recommend some beef tubes!

[jsu101]

What wheels are on the red one?

[buddamonk]

RC4WD Terantula 1.9

[k7zpj]

Originally Posted by cazper51

Very cool. Can't wait to see it come together.

Originally Posted by 79SCX10

Can't wait to see more!

Thank you. I been trying to get time to work on it, but the day job that pays for it seems to get in the way.

Originally Posted by buddamonk

Cant wait to see more...i was thinking about getting a 2nd JK kit and put wraith axles on with a brushless setup to mod it up to a JK rock racer...here is my current JK

Thank you and nice JK. I like the details.

Originally Posted by cox308

Awesome start and I really like how you're making this thread. Very well thought out.

I have the same motor/esc combo. You will need 32 pitch pinion and spur and you'll probably be needing metal driveshafts shortly.

Looking forward to seeing how you like it once its up and running.

If you're going to stick with the plastics axle housing's I'd highly recommend some beef tubes!

Thank you. This thread is a bit of experiment on how to show the difference from the stock build in an interesting way with out overloading the thread with lots of pictures. The 32p spur and pinion is in the bling pile awaiting assembly of the transmission. I exceeded the bling budget by quite a bit so the MIPs and beef tubes will have to wait a little while. The more bling I buy, the more I have to work and the less time I have to build.

Originally Posted by jsu101

What wheels are on the red one?

Nice Hijack !!!!

[k7zpj]

On my first SCX10 Honcho build I made sure to use lots of Loctite to make sure the set screw came. Work great until I had to take the drive shaft out. I am now using heavy duty shrink tube along with a very small amount of Loctite so that I can remove the drive shafts without a lot of work and broken tools.

Picture 1
1) I used a piece of shrink tube that is approximately ¼ inch long.
2) I placed the shrink tube over the drive shaft and put the drive shaft on the axle and tightened down the pin. I then put on a very small amount of Loctite on the exposed threads.
3) I then take a heat gun and shrink the tube down so that it is tight and will keep the pin in place.




Picture 2
4) I am using R2J Kustoms Stainless Steel links for the build with four links on both the front and back axles. The stainless steel links are strong and hang up a lot less on the rocks than the stock aluminum links. The links weren’t much more than what the Axial aluminum link set costs.
5) The shocks are completely stock with no mods. I want to see how they perform with the aluminum shock body and upgraded piston. I suspect that shocks will be on the upgrade list once the old bank account recovers from this build
6) Front axle with drive shaft, shocks and links installed.
7) Rear axle with drive shaft, shocks and links installed.

[k7zpj]

With the long week end I finally got enough time to assemble the transmission.

Picture 1
1) The parts include SuperShafty Beefy Top Shaft, SuperShafty AX10 "ULTIMATE" Motor Plate, Vanquish SCX10 Aluminum Transmission Housing, Robinson Racing Products Locker Diff. Gear, RRP Hardened Steel Idler Gear and RRP 56T/32P Steel Slipper.
2) I am using the stock output shafts with the RRP hardened diff gear.
3) The tolerances on the Vanquish transmission case are spot on. The bearings go in without a lot of force but will not fall out when shaken.
4) I am using the RRP hardened steel idler gear. Time will tell how well the aluminum diff gear will hold up against the steel idler gear. This was one of those budget tradeoffs that may turn out more expensive over time.



Picture 2
5) The SuperShafty Beefy topshaft (left) is longer than the stock top shaft to be able to mount the RRP 56T/32 Gen3 slipper. The holes drilled in the shaft have tighter tolerances than the stock shaft.
6) It takes some effort to insert the pin for the top gear on the shaft. The top gear slides on but there is no extra slop at all. The gear won’t fall off the Beefy shaft like when using the stock shaft. You have to pull it off to remove it.
7) All of the gears are in the transmission and it is greased with Lucas Red and Tacky grease.
8) The fit of the Vanquish transmission case is incredible. Once it is snapped together you really have to work at it to get it back apart.



Picture 3
9) I used the SuperShafty AX10 "ULTIMATE" Motor Plate (right) due to having more metal for better thermal mass for cooling, and longer screw slots for mounting/adjusting the motor while still being able to use the stock spur gear cover.
10) The motor plate comes with the screws and spacers to allow mounting to a stock sized transmission plate.
11) From the side view you can get a better idea of the thickness of the motor plate.
12) It is all clean and pretty for now, but this summer it will be out there crawling on the rocks.



Picture 4
13) The RRP slipper (left) has a larger disk and the slipper pad is on the outside edge of the disk instead of completely covering the disk like the stock slipper on the right.
14) The RPP spur gear is also the front metal surface for the slipper instead of being a gear that attaches the front slipper disk. The holes in the spur gear exposes some of the slipper disk material.
15) The bearing that comes with the Beefy Shaft is used as an additional spacer. It goes on the top shaft first. The stock metal transmission spacer goes on the shaft next.
16) The bearing and spacer are slide on the shaft until they clear the hole in the top shaft for the rear slipper plate.




Picture 5
17) Apply pressure to the spacers while inserting the pin for the rear slipper plate.
18) The tolerances for the holes in the top shaft are tight. The pin goes in but it takes a little bit of pressure to get it to go in. It takes a little work to get the pin but once the pin is in place there is very little forward-backward slop of the top shaft.
19) Next you slide the rear slipper plate on and make sure that is fully seated on the pin. Notice that the slipper pad is much thicker than the stock slipper pad.
20) The spur gear is put on the top shaft and slid backwards until it comes in contact with the rear slipper plate and pad. Notice that the spur gear covers the slipper pad and most of the rear slipper plate




Picture 5
21) The aluminum spacer is put on the shaft followed by the spring and spring retainer cup.
22) Screw the nut on to the top shaft and tighten it all the way. Back it off about 1 turn for the initial setup.
23) Front view of the transmission with the Spur/slipper clutch installed. Note that you can see the slipper pad through the holes in the spur gear.
24) The transmission is now mounted on the skid. Next step is to get the chassis assembled and power train installed.

[ussprinceton2004]

your build thread seem to be incomplete...any updates to this build?

[Richterat83]

I didn't have any luck with the reinforced stock driveshafts. I have since swapped to T-maxx shafts and they're holding up to the MMP and 13.5 Redline and rc4wd ax2 on 2s thus far. Have yet to try 3s

[2500hdon37s]

I'd go ahead and get MIP drive shafts. You'll never have to worry again.

Everything else looks to be bullet proofed. Only problem I foresee now is the Axial plastic upper 4-link mounts. I could see them breaking with that kind of power if you beat on it, I know even with a 30t hand wound brushed TM pro from Holmes hobbies I could easily flex the upper link mounts if on a high traction area or had a tire bind up.

Also what broke on the stock drive shafts that you reinforced? I'm going to build a new kit with them and would like to know if I should beef them from the start or just get MIP's. my old honcho kit came with the original yolk style shafts.

[k7zpj]

Originally Posted by ussprinceton2004

your build thread seem to be incomplete...any updates to this build?

Not yet. I kind of got distracted when someone gave me the R1 axles for my other build. I plan to start working on this one again once the raining season hits instead of out on the rocks playing with the rigs.

[k7zpj]

Originally Posted by Richterat83

I didn't have any luck with the reinforced stock driveshafts. I have since swapped to T-maxx shafts and they're holding up to the MMP and 13.5 Redline and rc4wd ax2 on 2s thus far. Have yet to try 3s

I tried the shafts I modified in my Wraith and found instead of twisting, they tend to break where the hub mounts to the shaft or the female shaft will split.

I ended up taking them out and using MIPs.

[Richterat83]

that's exactly the experience I had after going to big power