CR01 Custom chassis build

[OSRC]

I guess it was time to update anyway, it's been a while for this rig. Hope this helps Osteo

Overall side view, and a close up of the link area. The link set-up is basically the same as stock - basically I took the side plates and used them as a template and drilled out the holes on both sides. All of the holes in the chassis - upper links mounts, and upper shock mount areas are the same as stock - I did move the lower link holes up 1" in relation to everything else. Gave me more GC at the bottom, though moved the trans up into the chassis quite a bit. Also changed the geometry enough that I could no longer run the stock spring set-up even if I wanted to.

A look at the suspension set-up. The GMade shocks are awesome on this platform. It's not quite a droop set-up as the piston floats between a set of springs, and they can be set up in a long or short fashion. I like the short set-up...basically it gives about 1cm of uptravel to absorb bumps, and gobs of sprung downtravel to allow the axle to drop out/flex down. Took a little tuning, but it's spot on now. Very stable and predictable. Also a shot of the beefy KM steering upgrades. Very nice parts!

View from the top. By moving the trans mount up in relation to the rest of the chassis, it pushed the stock trans up quite a bit, so I replaced the trans with an axial trans as it was much shorter and allowed the battery to sit lower. Plus, the Axial trans has outputs much lower in relation to the stock trans and really helped the driveshaft angle. The battery mount is a leftover transmission mount with an integy battery tray bolted on. Works like a charm!

A little crowded in there, but it all fits. Running a sensored 17.5t BL set-up.

 

[Osteo]

"thumbsup""thumbsup" OSRC - thanks for the pic's, that helps a lot. Now I'm just waiting for my metal blade for my bandsaw to arrive and the cutting will begin! Droop shocks are on order and should arrive this week, tires arrived yesterday.

Hmmm... good point with the Axial Trans, I scored some Axial axles for cheap from a buddy (and his shocks, so now I have a 2nd set for the other truck), maybe I can convince him to upgrade his tranni and I get his old one?! - I think a phone call is in order.

 

[Osteo]

OK, another question... I see the rear lower link arms are the bent ones and the fronts are straight, any reason for doing so?

 

[OSRC]

Gives a little extra clearance for breakover.

 

[Osteo]

Gives a little extra clearance for breakover.

gotcha! good thing I have a set! and I mentioned to my buddy I did not really want his Axial axles (although for $40 for the pair...) but I do want his Tranni if he is going to upgrade it... and that was all it took! one just has to open the door and in this case, he walks right on in!! Tranni for $40! by the time I get it, it will have maybe 2 batteries through it! :mrgreen::mrgreen:

 

[OSRC]

The stock trans is a straight up brute. I've put some power through it (Revolver motor on 3S, and a Castle 4 pole SC system for some fast runs) and it's never complained. It's just big and overbuilt, in typical Tamiya fashion. The axial is a more compact unit. An RC4WD R2 was considered as well dues to its low profile, but interfered with the link mounts.

 

[Osteo]

G-Transition shocks arrived today, got the bandsaw on crazy sale last weekend ($72!!), blades arrived 3 days ago, aluminum is marked for cutting, now I just need a few hours to get the work done! Not going to put in the Axial Tranny just yet, so will cut the chassis and raise the stock tranny 1/2", but make mounting holes for 3/4" as well and see if the driveshafts will tolerate that 3/4" height. If they do, I'll cut off the 1/2" holes.

Hopefully Sunday, the wife has me removing sliding glass doors Saturday and installing double garden doors in their place!

 

[OSRC]

Rule number 1 of RC: Always take care of the honey-do list first. Happy Wife, happy life!

 

[Osteo]

Hey OSRC - finally getting around to working on my new chassis, have it all cut and holes drilled and now I'm just fitting all the parts in. I've got my CR01 Tranni installed and as you said it sure does take up a lot of room... so I think I may try to track down an Axial Tranni.

Looking at your pictures with the tranni, that large spur gear, is that the slipper clutch? I found some tranni's on Fleabay but some do and do not have that large gear and didn't know if it really was needed.

Would this work?

Axial Wraith Transmission Complete Gear Box Case 4WD AX90018 AX80051 AX30198 | eBay

Thanks
D

 

[OSRC]

Yes, that is a slipper. The older AX10 transmissions do not have one, but the newer ones do. And the new, new ones have a dual slipper - they are starting to pop up on Ebay too.

Your link is only the center gears and housing - about 3/4 of a transmission. You'd have to buy the spur adapter and assembly, as well as the motor plate. Might be easier and cheaper to just find a whole complete transmission.

Axial SCX10 Transmission w Slipper Clutch AX30487 Honcho Wrangler Scale Crawler | eBay

 

[Osteo]

Yes, that is a slipper. The older AX10 transmissions do not have one, but the newer ones do. And the new, new ones have a dual slipper - they are starting to pop up on Ebay too.

Your link is only the center gears and housing - about 3/4 of a transmission. You'd have to buy the spur adapter and assembly, as well as the motor plate. Might be easier and cheaper to just find a whole complete transmission.

Axial SCX10 Transmission w Slipper Clutch AX30487 Honcho Wrangler Scale Crawler | eBay

Ahh, I was starting to think that, thanks and thanks for the link that is a big help. I don't mind tinkering and making up stuff but that would have frustrated me to no end!

D

 

[OSRC]

Lots of little parts to find - kind of a hassle! Be sure to post up some pics of your project

 

[OSRC]

My first carnage!! Backordered this when it was first announced, and have been running it since. Didn't think the cast gears would last this long, but years of crawling, brushless, outrunners, and even a set of clod tires for a while took its toll. The teeth are so sharkfinned, they are almost sharp!

Even with the pieces flying around in there, finished the trail run and back to the truck. First thing that's ever broken on this truck.

 

[Osteo]

My first carnage!! Backordered this when it was first announced, and have been running it since. Didn't think the cast gears would last this long, but years of crawling, brushless, outrunners, and even a set of clod tires for a while took its toll. The teeth are so sharkfinned, they are almost sharp!

Even with the pieces flying around in there, finished the trail run and back to the truck. First thing that's ever broken on this truck.

That's not bad after years of (ab)use!

Question - in another thread you mentioned JB Welding the gears to lock the diff (of course I can't find the thread now), where in the gear box did you pack the JB Weld, inside the hole that the locking pin goes into? did you open the housing and pack the hole that would receive the locking pin ? or just jam it inside the hole through the housing?

 

[OSRC]

Inside the diff are a bunch of gears - 2 sun gears and 3 little planetary gears. I added 3 more little planetary gears to jam it up nice and solid, and then added some JB weld inside to take any play out. JB weld is overkill though, with the extra gears in there it locks up nice and solid. Even just adding 1 gear does the trick.

Great pic here: http://www.rccrawler.com/forum/tamiya-xc-cc01/414298-new-rc-trucks-cc01-3.html#post4103364

 

[860Crawler]

I haven't blown that set of gears out yet (knock on wood)

 

[OSRC]

New wheels and foams for the old girl. Dual stages from Proline - seems to work best in a 4.5-5" tire. Left the Losi tires though, really like how they grip.

 

[OSRC]

Been a looonnnnnng time since I posted anything in a CR01 thread. Can't believe those pics are still even here. Photobucket deleted my account years ago.

In any case, I was headed up to the mountains for a long weekend and needed to take a truck that could accomodate 5000mah packs for some long hikes.... Both TRX's are down, SCX10v2 is under construction, just sold a bunch of trucks, and my others 2 only fit 2200 packs. Wraith was good, but I just rebuilt it back into a 2.2 and was a bit nervous about taking it out without a shakedown run and tools nearby. Looked at my trusty and dusty CR01 sitting on the shelf...the only other one that still fits a bag pack. Why not? What better way to blow some dust off than to let mother nature do it?

So packed up and headed out.... Beautiful....leaves are just starting to change here in Julian PA, about 15 miles from State College. Set out from the cabin where we were gathered with the family for a little solitude, RC style. Just had my radio, 3 batteries, some water and powerbars in the bag. Let's get hiking!

Mostly trails that were cut in by loggers or 4 wheelers, so there was not much that gave the old girl much of a challenge. I did find this creek bed, and crawled up it for almost an hour until it petered out.

Stock steering on these trucks is laughably bad by today's standards. I use 4WS which keeps things interesting, and gives it some much needed agility. Plus it looks cool...

35t motor and a newly installed WP1080 gets the job done when needed. Just enough wheelspeed to get out of trouble.

Moving up the mountain, came to a pine tree area... Multi colored ferns on the ground were just breathtaking. Pics can only show so much.

Lots of roots in this area made for fun trail running. Got to cycle those old Gmade shocks - not even sure if they even have any oil in them anymore, though it doesn't seem to matter.

Made the switch later to some PL wheels and old Rock Carvers - a lighter setup that was a bit more suited for trail running. Don't look nearly as cool though.

Old or not, this old truck still gets down... Not even breaking a sweat!

Not all was sunshine and rainbows.. Took a nasty tumble while going up Heart Attack Hill, a very steep logging road that leads to the top of the mountain. Barrel rolled about 20 feet on a sidehill gone bad. The CR is tough, all was well! Flipped her over and kept right on trucking.

At the top of the mountain, I rode along the ridge for quite a while. I picked up a hitchhiker....this little grasshopper jumped on dead center on the roof and stayed on top for a good 30 minutes or so! Needed a rest I reckon.

In the end, I hiked for almost 4 hours, and it was mostly trail running - very little technical stuff other than the creek bed and some roots/trees so I was running flat out or at high speed quite a bit. Didn't even tap the second battery, still had 15% left. Amazing....this CR01 is pretty heavy too since it's all metal. Zero broken parts and zero problems - the old girl still runs like a champ. Glad I got it out!

 

[AK KRAWLER]

Awesome run man and great scenery.

Not many times in your life you get to see a beetle giving a grasshopper a ride...:lmao:

 

[OSRC]

Trying to keep myself busy during the "pandemic" I've got a lot of projects going on...

In real life, I've got my Xterra torn down for frame painting, new exhaust, rust remediation, and painting the plastic cladding. I've rebuilt my 4 wheeler with a new carb (thanks ethanol) and fired it up for the first time in years. Also, I'm rebuilding a 15 year old deck around our pool which is proving to be a hell of a lot more work than I thought.

In 1:10 life, I've got builds going on all over. 2 trucks for the upcoming G6, 2 OG SCX10 builds, a Tamiya hybrid cawler project I just started yesterday and in the middle of all that, I decided to give my old CR01 some love.

This particular CR was backorded when they first came out, and I've had it a long time. It's been changed a lot over the years, but it's still smooth, still in 1 piece, and most of all it's pretty capable. On its last outing I ran it for about 4+ hours and it toured all over a mountain, impressing me the entire way. Been a long time since I tore it down, but it was way overdue.

Cleared off a small space on the workbench and got the old girl down... rode hard and put away dusty.

Had an Element gearbox ready to go....It's already running a 3 gear SCX trans, so this should drop right in. A little front OD never hurts, and there's no other way to do it with CR axles. It already crawls incredibly well, should do great with the OD.

Build, sanded the bottom flat and swapped over the motor.

Messy workbench! If I pan 360, the rest of the shop looks just like this sadly. Forgive the blurry shots, I apparently had some WD40 overspray on the camera lens.

Doesn't look it, but I spent about an hour with files and other blunt shaping instruments cleaning up the chassis. It was way thicker than it needed to be in spots, so I did some cleanup. Also added some speed holes here and there just to break it up a bit. I gave everything a coating of dark bronze so the chassis is all one color. Already looking much better!

New transmission tucked in.

Cleaned the axles, joints and driveshafts and re-greased where needed. Cool thing about these axles is I can check the ring gear without pulling apart the entire axle, which if you ever ran a CR01 you know those axles take an entire afternoon to tear down and rebuild. Also replaced 2 rod ends that were really loose.

And back to a roller again! Well, almost... a 1080 ESC is on the way. Love the old school Losi tires, they may not be scale, but they grip very well. They are stuffed with some older PL 2 stage foams and are perfect for this rig.

4WS is a must for this chassis, since I can't get any more steering out of the dogbones, and there are no CVD's out there, so you really need the rear wheels helping... I set it up for individual control on my GT3B. I've got a mishmash of servos on here, eventually I'd like to replace them with a matched set. The front one works and is still strong, but sounds like death. That can't be good!

For the rear steer, I can't figure out what to run as far as caster. So far, this seems to work well...not sure if I'd be better off with 0d of caster or not. I have 4 settings to mess with, I'll have to experiment one afternoon.

Just for giggles, I put some 1.9 Flatirons on.... they are a bit taller than the Losi's, but not nearly as wide. Looks pretty decent, may leave them on for the next run.

And done! Next project!!