Why can't I find articulation mod?

[crazy88]

Everyone talks about the articulation mod, but even searching for it, I can't find it.

I have a Zip Zaps Monster Truck in need of some articulation lovin', and all I can tell is that you cut the chassis in half to articulate over a modified drive shaft, but how is the drive shaft modified?

Please help, and thank you for anything I get.

[chilli_mp138]

crazy88--

I'm not sure there are any "formal" tutorials on articulating MTs, just "notes" here and there.

If you haven't already explored the "Wheel Weights" thread, look there:
http://www.tinyrc.com/forums/showthr...threadid=21347

I'm likely to do that mod later this summer and then write a tutorial to add to the rest of mine.

chilli
www.gcrossett.com/zipzaps/

[Steve]

[quote]Originally posted by crazy88
Everyone talks about the articulation mod, but even searching for it, I can't find it.

I have a Zip Zaps Monster Truck in need of some articulation lovin', and all I can tell is that you cut the chassis in half to articulate over a modified drive shaft, but how is the drive shaft modified?

Please help, and thank you for anything I get. [/QUOT


OK, I'm going to try and explain it the best I can. The factory drive shaft kind of floats in the "hull" of the chassis. When you lop off the rear end, you need something to keep the drive shaft and the rear end attached to the truck as the chassis will be in two parts. Putting a sleeve around the drive shaft allows you to make a channel for the drive shaft to spin in, attach that to the chassis. The bearings allow you to fasten things to the outside of them, while still allowing for the inside to spin. SO, the sleeve keeps the drive shaft assembly attached to the trucks main body, and the back end, attached to the outside of the bearing allows the arse to swivel on that point, and the gear inside the rear end, on the very end of the drive shaft, actually keeps the rear end from separating from the rest of the truck.

The reason for the modified drive shaft is that the bearings I pulled from a CPU fan didn't fit the factory drive shaft, and finding a sleeve that is just slightly bigger than it is tough. I actually used an extending antenna as all the parts fit perfectly inside of eachother, and the end piece, which is solid, fit my CPU fan bearings. Oh, and it's all chrome so it looks cool as hell.

The wheel donut thread has info on it, and a dude named Diets I think, was the first one to actually prove to the MT world it would work.

Word of caution though, this is one of those mods that is easy to screw up, and once you do, there's no going back. Patience is the key, as is having like 6 hands to keep everything together. Mine is also high maintenance as those motor wires keep coming apart due to all the flexing they go through. I will say it is definitely worth it as it gives the truck awesome offroad ability, and stability. It also looks pretty wicked...see video here

[crazy88]

So, I found the right link to a forum that somewhat discusses the mod, very much the same way as Steve did:

http://www.tinyrc.com/forums/showthr...threadid=20849

Thanks Diets...

and my results were astounding. I used an old antenna I had lying around and took it apart. I then cut a portion of the section that was slightly larger than the drive shaft and used that as my sleeve. I hot glued it between the charger plates inside the chassis and cut away a lot of plastic (the truck would bend inward \/ a slight bit and then the two halves would rub... also when it articulated far enough, the rear tire would catch onto the side of the other half and lock up the wheels while trying to drag itself into the floor). Nextly, I had to reassemble the truck. I had cut away the battery holding tabs, so I dabbed hot glue on the battery and anchored it to one side of the chassis. THEN, THIS IS THE BEST PART, I knew I had to have a LOT of travel, but I also HATE HATE HATE soldering those little wires, so I 180-ed the PCB and aligned it with the front of the chassis, because thats how far the servo wires would stretch. This also allowed for a good 1.2 inches of motor wire to be sitting freely for great articulation. AWESOME wire travel with NO modding of the wires. I hot glued the PCB edges to the truck (I HAVE no intention of disassembling my WORKING piece of art). This also got my PCB out of the way because replacing it would block the articulation. ..

THE RESULTS PLEASE:
A truck that can easily articulate one axle a full 90 degrees from the other. That's right... one axle can be flat, and the other on its side and the truck still be firmly planted, motor running, servo turning. It could go father around fluidly, but theres no way the truck could drive that way... I also left a LITTLE give in the axle sleeve so that the two halves could bend inward a little, when turning the inside wheels become closer, and the outside ones farther. This allows for a noticeably tighter turning radius with no modding of the steering mechanism. It also gave it another dimension of articulation.

Combined with the simple 3/32 drill bit on front suspension mod... (a super easy mod totally worth the trouble ((actually, no trouble))) this truck is rarin to go anywhere, and otherwise its completely stock.

NOW, I just need suggestions on how to lift and mount the body to allow all this amazing kickass articulation...
AND cover the PCB and insides of truck, which are exposed now that the PCB cover is totally worthless and the battery and motor wires are exposed to the elements... so please help with that...

[Steve]

Glad the mod went well for you.

As for the body, I put a piece of lexan on the back part of the rear end, so that it extends up into the bed of the truck body. It acts as a stop so that the wheels don't articulate too far and hit the body. The lexan piece hits the inner side wall of the truck bed when the wheels get close to hitting, otherwise it just sits freely under the bed. It limits articulation, but it still allows for quite a bit of movement.

Another option. I seperated the bed of the truck from the cab, and mounted the two halves on their corresponding chassis part. SO, when the truck was level, it looked perfectly normal, but during articulation, the two body halves could twist freely. This actually worked really well, and even looked pretty cool.