My rear diff housing theory

[DemonRC]

Well I added 1 + 1 together and ended up with 2.


One, about a month ago, I did a nasty jump and landed right on my ass. It landed back right side up and when I started off again I heard a clanking sound. Well the rear dogbone was bent and was hitting the bottom of my engine. So common sense will tell you that the rear end flexed causing the dogbone to get jammed between the center tranny diff cup and the rear center diff cup which bent it. Also, my fiberglass reinforcement around my rear diff bearing was cracked off. So that also tells me that the rear end flex jammed the dogbone, bent it, put alot of force on the rear diff cup, and stressed the hell outta the housing.


Two, last weekend I landed on my ass yet again coming off a jump. The car did two to three endo's. I turned the car back over and hit the throttle and was in front wheel drive only. Guess what. The endo's must've locked the rear dogbone again and blew the rear cup straight up out of the diff housing.


On both wrecks I was off throttle when landing so drivetrain shock wasn't the cause. Well, as soon as UPS gets here I'm installing my new diff housing. I made a brace for it which looks like a 1" conduit brace you can buy off the shelf. I'm going to add some epoxy on the diff housing and install the brace. Then I'll drill through the brace into the bottom of the diff housing and put in some 4mm bolts with nuts. After that I'm going to fiberglass the entire area.

 

[alfred e numan]

what type of glue

[Yea, the buggy took a hard hit, say- what type of glue are ya gonna use on the diff housing? Epoxy is strong with fiberglass- what about c-a -superglue-fiberglass? Just thinking the superglue might fuse onto the plastic. I posted a crazy idea the other day- Here it is agan- Howbout a flex drive for cars- like what drives the weedeaters we all use- swadged ends, absorb shock, be hard to retrofit on a car for shure, This is very durable on my weedeater- hitting the cyclone fence with the throttle full tap- just flexes and keeps on rippen weeds out of the ground. Just an idea.

 

[DemonRC]

Here's the steel band all installed:









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[Guest]

Looks beefy. Im curious to see if you can break it. Lol

Did you have one of your cages on when this all went down?

 

[DemonRC]

I just had that buggy spark plug protector on. It doesn't help flex any. Just protects the plug.

 

[Rapidito]

Here's another victim:







Does anybody try this? Does it fit the Xb:

http://risenrc.com/aluminum-differential-gearbox-p-10.html

 

[k.jensen]

Does anybody try this? Does it fit the Xb:

http://risenrc.com/aluminum-differential-gearbox-p-10.html

my problem is with the holes in the side of the gearbox where the drivecups are. but I've wondered 2 if that alu gearbox would fit, but a supplyer here in denmark said no.

 

[Guest]

I think 7075 said that was the next hop-up to be produced

Ya might want to contact him may he can give you some specific info.

 

[DemonRC]

He might not if the factory is going to fix this soon. Personally, I think we just need a cheap brace to go over it and then bolt it down though the diff.

 

[LightForce]

Plastic brace same idea http://www.redcatrampageforum.com/showthread.php?t=6476 as metal worked for a while 2.5 hours of race abuse instead of 20 min but flexing of the chassis even with multiple Delrin rods supports for cage worn out the housing and screws holding the brace were pull out of the housing. Metal brace prob. better but screws must be drilled thru the chassis with nuts and washers might triple the driving time.Hope.

 

[DemonRC]

Plastic brace same idea http://www.redcatrampageforum.com/showthread.php?t=6476 as metal worked for a while 2.5 hours of race abuse instead of 20 min but flexing of the chassis even with multiple Delrin rods supports for cage worn out the housing and screws holding the brace were pull out of the housing. Metal brace prob. better but screws must be drilled thru the chassis with nuts and washers might triple the driving time.Hope.

Hey I made a spare. I'll send it to ya if you wanna try it. Just order me a stocker so I can fix it up like this one.I epoxied the ends of the nuts. The bolts might hold better. Also, the bolt holes were undersized. They were tight as hell to going through the plastic.



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[cordy]

Thank you Demon. Very good idea .

 

[Raily]

This is my extreme gearbox fix, i will not explain to much because of my english but photos speak for themselves

 

[Raily]

 

[Raily]

After hours of hard bashing and stay intact

 

[Deluge]

Whoa. That's definitely beefy. Good stuff.

 

[cordy]

Yes very good,a lot of work.

 

[DemonRC]

Holy crap. That's defintely beefy. Let us know how it holds up. My metal strap is holding good so far. We'll see how it does after another week.

 

[Raily]

Yes very good,a lot of work.

yep,I spend a full day and I have no special tools, all the fabrication was made with a Dremell a drill and 4 1/2 angle grinder

 

[Raily]

Holy crap. That's defintely beefy. Let us know how it holds up. My metal strap is holding good so far. We'll see how it does after another week.

at the end, I think I found the cure... after several hours of abuse my gear box is holding like a champ

this is responsible for my problems