RC18 Center Diffs

[Lessen]

Ok guys. The indoor ramp is done so it's on to a new project...

I've done a lot of measuring and a lot of brainstorming and I'm about 98% sure I can make a center differential for the RC18 series of 1/18 scale vehicles. I'm going to be working on 2 versions.

1: A standard type differential

2: A RWD bias differential. Basically this one will keep the rear diff turning in constant conjunction with the spur gear while the front drivetrain will be able to (essentially) turn slower. I got this idea specifically for dirt oval converted vehicles.

 

[Lessen]

Here's the basic idea for the RWD bias diff. I'll be doing this one first only because it'll be slightly easier to make. Still a lot of modding though.

Oh yeah, I'm sure you notice the outdrive going toward the front. I'll have to install a cross pin through the cut down driveshaft. The single hardest mod will be trying to drill a hole to accept the thrust screw down the center of the short driveshaft

 

[Lessen]

Interesting. Looks like not much interest in this project. Well anyways... I'll be posting before and after pics of all the parts I need to modify. Let's start with the spur gear and driveshaft

this the the rear face of the spur gear.. which when installed will end up being the forward face. The extruded shaft section needs to be completely removed on this side.

here is the forward (rear when finished) face of the same gear. The small wide ring needs to be removed so that it is the same diameter as the longer section. Then the overall height needs to be taken down to about .095-.1 inch. After that is done it needs two slits at opposite corners of the hex that go down to the gear surface. Oh, and don't forget about the 8 holes for the Ball bearings.

you'll notice in the picture that one side of the extrusion has a funky cut in it. This is so the pressure plate will fit. This goes against my diagram but then again it was just a sketch. It is important that the slit that comes into contact with the narrow milled section of the extrusion is cut on the left (counter clockwise) end of the narrow area. This will ensure that the cross pin will have the strongest surface possible when under power.

The driveshaft needs to be cut in two pieces. I'll cut it about 6mm to the inside of the wide hex (along the outside of the marked line). A .07 cross pin will be installed in the end of the long shaft while the shorter piece will be utilized and further modified later.

 

[retarded pilot]

really late but you have my interest....

any progress on this? looks very cool

 

[Lessen]

kinda gave up on this one. I didn't take into consideration the fact that there would be very little material for the screw to fit into when the crosspin was installed (on the gear side shaft). I couldn't figure out how to make it work w/o having custom parts made, and I can't justify spending that much money on this little project. I still think it's a cool idea though. I'm sure if some aftermarket company made a center differential that people would buy 'em up.

 

[retarded pilot]

thats a shame, good idea though...i agree if a company produced these there would be a market.

 

[redhatman]

awe man, I was gonna watch this thing. Where did you get that end driveshaft (silver) thing with the pin through it?

 

[Lessen]

Where did you get that end driveshaft (silver) thing with the pin through it?

I made it froma stock rc18 shaft. The silver is just where I took the anodizing off.

 

[hamz9561]

I was hoping you could get it to work. I would have bought a couple of them.