Capo 1582-2 Tatra 817 8x8 and Cross MC8 Man Kat 1 8x8

[Prop Shaft]

This will be an ongoing journal of these 2 models I bought recently. I will try and keep things current as I have some rather ambitious plans for both. For starters, size comparison between the capo and cross 8x8's. And a shot of the scale motor build of the capo.

[Prop Shaft]

Tore into the drive train a little bit and boy im glad i did. Not only was nothing greased, but most of the screws i have taken out were loose. And a couple were backed out completely
Started swapping out socket head screws for scale hardware


An interior is in the future for sure

Heres something a little unnerving. The only thing holding the cab onto the chassis is 4- m2x5 screws.

Lots of room in the back of the cab for electronics

Another area of concern. The cab mounts to the front bumper/skid. The bumper/skid mounts to the chassis with yup... 4 m2x5 screws. They seem to have some play in them. I will be putting longer screws in at the bare minimum. Hopefully they wont need to be drilled and tapped with a bigger size down the road

The entire bed is only held on with 4 m3 screws as well. Not much i can do here as the hole aren't tapped very deep. i just hope they hold up.

With the bed off

Another thing im not fond of, under compression and full lock the front wheels are going to be rubbing the shocks pretty bad. Uncompressed

Compressed

More to follow soon.

[Prop Shaft]

Underside

Remove 8 screws, the shocks, and the 4 diff lock arms to separate the driveline from chassis


M2.5 hex head to remove the hub covers

This allows access to the standard m4 size nut that holds the wheel on
I also noticed that on the rear wheels the nut bottoms out on the shaft before the rim. Leaving the wheel a little loose. I will have to shim it.

Back side of a wheel. What a nightmare it would be if you had to remove 10 m2 nuts to get each wheel off!

[Prop Shaft]

Diff unlocked

Diff locked.

This diff scares me. For how heavy this truck is theres such a tiny bit of mesh where these planetary gears touch... I cant see this being very strong
This was fun to put back together. I had to grease the shift fork, but not so much that grease squeezed into the hole that needed to be thread locked. Then i had to hold the parts inside the tube lined up to the hole and try to thread the link mount into the fork, while being careful not to loose the bushing ...

A break down of a front half axle

And one reassembled, thread locked and scalified

I managed to tear a boot, thankfully there were extras included

One axle greased and ready to go, now only 3 more to go.....

Reassembled and scale hardware added... There are so many screws on this thing its crazy... I love it! Lol

[Prop Shaft]

so theres 4-m3 tapped holes in the bottom of each axle case. Im not sure why they are there, other then maybe for adjusting the the ride height lower, or maybe skid plates...

I filled them with some screws to keep dirt out

I changed over to tamiya ceramic grease. I was worried about the sticky black grease not getting to the areas where the planetary's shafts etc. spin and not being lubed. The tamiya grease is alot lighter and flows a bit into all areas from what ive seen.

Another area where theres a big issue is in the front steering geometry. Everything works dandy with the steering until you add compression on the front axle. At which point the steering arms hit on the top of the axle. I played around with some offset rod ends I had laying around, and it seems they will suffice to remedy the problem. All i had was short ones, I have some longer ones ordered ill replace them when they come in. Too bad they're plastic.... I cant find any metal ones. This is the steering angle at full lock.

This is as far as it turns before it binds under full compression

Cracked open the 2 speed transfer case

Gave it a good dose of grease

When i cracked open the 3rd axle housing. I noticed one of the bearings had fallen out of it seat. Theres nothing to hold it in place. Looking closely at it, the bearing is actually 2 bearings pressed together to make one. Kind of odd.

I shimmed it with some washers to keep it seated.

This is where it sits at now. Its proving to take quite alot of time to swap out the many many screws.

[Hammer!]

looks really neat!!

[Prop Shaft]

Originally Posted by Hammer!

looks really neat!!

Thanks, this truck is a dream. I cant wait to get it running!

[Prop Shaft]

Started swapping out the fender bolts, i may or may not keep the washers. Im undecided so far.

Im having a hard time deciding on paint color... Leaning towards nato green...
Im definitely open to suggestions...

The rear axles halves are pretty much identical for all 4. There are m3 holes on the sides that don't have the coil overs. I figured id fill them with some grub screws to keep the dirt out.


Fuel tank removed. I want to fab up some sort of skid plate for it so i dont end up tearing it off.

Changed the m2 screws that hold the front bumper on. I put longer ones in as this is a critical area as it holds the entire cab on!

Mounted up with new screws

[Prop Shaft]

2-m2.5 screws fastening each cab hinge to the bumper. With only about 3 to 4 mm of thread actually holding the hinges on, i was concerned about them being strong enough. So i tapped them all the way through and used longer scale hardware.

This is what it looked like from the front prior to tapping

New screws bolting on the hinges

From the front

After scale hardware added to the grill

Started mocking up a fix for the front wheel scrub issue with the coil over


Offset link ends added. This stops them from hitting the axle under compression, i just wish i could find some metal ones.

Full lock and compression, and no binding! Tomorrow I'll replace the styrene with aluminum and make them look presentable.

[rockhugger]

this thing is beautiful.... I want one. Keep up the good work.

I'm still trying to figure out how that locking diff mechanism works, either way this rig looks packed with cool features, 2 speed transfer case...

[Prop Shaft]

Originally Posted by rockhugger

this thing is beautiful.... I want one. Keep up the good work.

I'm still trying to figure out how that locking diff mechanism works, either way this rig looks packed with cool features, 2 speed transfer case...

Thanks. I had a hard time grasping how the diff worked as well until I was able to tear one apart. The locking part is real simple, there are fingers that get jammed into the planetary gears stopping them from rotating.

[rockhugger]

Originally Posted by Prop Shaft

Thanks. I had a hard time grasping how the diff worked as well until I was able to tear one apart. The locking part is real simple, there are fingers that get jammed into the planetary gears stopping them from rotating.

Ha Ha, that was the easy part to figure out, and I thought what an ingenious device.
I'm trying to visualize the gears Diffing, then being locked, which ones spin, before and after, and then how the power flows through once locked... no big I'll just wait till I get my own

[Prop Shaft]

Originally Posted by rockhugger

Ha Ha, that was the easy part to figure out, and I thought what an ingenious device.
I'm trying to visualize the gears Diffing, then being locked, which ones spin, before and after, and then how the power flows through once locked... no big I'll just wait till I get my own

I wish i would have thought to take pics when i had one torn down. Easiest way i can try and explain it is, there are basically 3 shafts that spin on the centerline. The smallest is fixed to the planetary diff cage, then one is sleeved over that shaft, it receives power from 1 half of the diff and is connected to one of the pinions that feeds a ring gear. the other is sleeved over the already sleeved shaft taking power from the other side of the diff and feeding the other ring gear. That make sense? Lol prolly not.

[rockhugger]

Yes, that makes sense, I couldn't see the cage, but now I got it. thanks

[robertjpjr]

Have you checked out djmedics videos on this? Had a huge buildup and then he said he hated it. I hope you're journey turns out different.

[Prop Shaft]

Originally Posted by robertjpjr

Have you checked out djmedics videos on this? Had a huge buildup and then he said he hated it. I hope you're journey turns out different.

I did watch his videos, very closely too. I heard he said he hated it, or it was junk or something to that affect. I just wish he would elaborate as to why or what he doesn't like about it.

[Prop Shaft]

Well after testing a few different paint colors I had laying around, Ive decided to try and match the darker green of Capo's anodizing. Ive ordered some darker greens in hopes of getting a closer match. Im thinking black green might be the ticket. In the pic is nato green on the left, olive green on right, and the factory anodizing color on the bottom.

[Prop Shaft]

Finished my modifications to the #1 axle shock relocation. 1/8" aluminum plate mounted to axle halves.

Same size plate used to relocate the upper shock mount

Had to drill and tap some new m3 holes

Sprayed some olive green onto the plates

Everything jives now, no binding and max steering angle

Full lock, uncompressed

Full lock, compressed

[Szczerba]

The Capo looks super trick. Your steering mod looks much needed.

Have you ran the Cross RC rig yet? I am about to buy one of their 6x6's.

[Prop Shaft]

Originally Posted by Szczerba

The Capo looks super trick. Your steering mod looks much needed.

Have you ran the Cross RC rig yet? I am about to buy one of their 6x6's.

I've run the Cross a total of 2 times. The axles are just horrible. I've had to super glue them back together after they basically shattered, and even after that, the gears skip in the #3 axle when any sort of real torque is introduced. I have a set of yota 2 axles I plan on swapping in when I can find the time. Basically its a great kit aside from the crappy axles, complete garbage drive shafts, and the week plastic upper spring/shock mounts. but like I said, I'll be addressing these issues soon as I can find time.