How To: Make "Blade-type"
Universals for your Mini-Z AWD
This short little tutorial comes to us via Peter Chan, from Toronto, Canada. Peter figured out a way to bring new life to your worn out differential outdrives (especially aluminum ones), while at the same time improving efficiency and durability in your drivetrain.
"Blades" as they were coined by Schumacher RC about 10 or so years ago, are flat, half-moon shaped attachments that snap over the dogbone end of universals. The advantage of using blades is that instead of a round pin making contact with the outdrive (which is what wears it out) you have a wider, flatter piece that turns the driveshaft. The larger contact area distributes the force from the rotation over a larger area therefore decreasing wear on the outdrive. Blades also have the effect of being a tightter fit in the outdrive over the pin, which decreases slop in the drive train as well.
To complete this modification you will need a couple of stock Kyosho Universals. The stock universals can be broken down into 3 pieces; dogbone, axle and pivot. We will be using the half-moon shaped parts of the coupling on both the dog bone part and the axle part. Take some flush cutters or an X-ACTO knife and cut these pieces off the axle and the dogbone.
Notice how we took the half-moon shaped part of the coupling and we clip it into the dog bone end of the universal. This is what is known as a "blade"
The next step is to take you differential and carefully grind or file away your irregular outdrives to make them flat and wide enough to slide the blade in without any trouble.
Check the outdrive often and grind a little bit at a time. You want the blade to slide in easily without any effort, otherwise your drivetrain will bind. You also don't want to grind away so much that it becomes sloppy and negates the benefits of the blade set-up.
You are done! Both your universals and diff outdrives should last much longer now. Your car should also be quieter and smoother as there won't be a pin or grabbing the outdrive or slaping constantly against the outdrives under braking and acceleration.
Words by Peter Chan and Cristian Tabush
Pictures by Peter Chan