Shock Building TipsBy Axial on May 20, 2009
Here’s a few pointers for assembling Axial’s new comp shocks for optimum performance. Building shocks is fairly easy, but paying attention to small details makes a huge difference in how they perform. Nothing is more annoying them rebuilding a set of shocks only to see they’ve started leaking after a couple runs. So let’s get started…….
First step is assembling the shock cartridges. Here you can see I’ve laid the parts out in order.
Start by lubing up the rubber o-rings with grease. This helps eliminate any chance of tearing the o-rings when you install the shock shafts into the cartridge. Just put a dab of grease on your finger and cover the o-ring with grease throughly by rubbing it between your fingers.
Now install the first o-ring inside the cartridge body.
Set the plastic spacer on top of the first o-ring and press it down until it stops.
Lube up the 2nd o-ring and set it in place on top of the plastic spacer.
Then snap the top cap onto the cartridge body.
Now install the supplied o-rings onto the base of the shock cartridges.
You’ll want to slide the shock shaft into the cartridge from the bottom, or left to right as the pictures indicate. If you slide it in the opposite way you run the risk of tearing the o-rings inside the cartridge with the M3 threads for the lower rod end. Since the shock piston is held in place with a smaller M2.5 Nylock nut the threads are less likely to touch the o-rings when you install the shock shafts. Wipe off any excess grease that is on the top of the shock shaft after sliding it into the cartridge.
Now it’s time to install the shock pistons. You can see I’ve laid the parts out again in order as far as assembly goes.
Install one flat washer onto the top of the shock shaft, then slide the piston into place and install the second flat washer. Hold onto the flats on the lower portion of the shock shaft with a set of needle nosed pliers and thread the M2.5 Nylock nut onto the threads at the top of the shock shaft and gently tighten it down. This nut doesn’t need to be tighten up a bunch, just thread it on until it stops.
Next decide which lower rod ends you want to use, for SWX builds I’d use the shortest rod ends on the left of the parts tree.
Slide the included rubber bump stops onto the shock shaft and thread the rod end into place. Again holding the flats on the shock shaft with a pair of pliers. Make sure you install the rubber bump stops too, because these will prevent the flats on the lower section of the shock shaft from entering the shock body at full compression. If the flats are allowed to go inside the shock body you risk them tearing the lower o-ring seals over time.
Now it’s time to prep the threaded aluminum shock body.
Start by inserting the supplied o-rings into the threaded pre-load collar.
Then thread the pre-load collar about 1/2 of the way down the shock body.
Now thread the cap onto the shock body and tighten it down as tight as you can with your fingers. If you use pliers you may unseat the bladder which will cause the shocks to leak. I’m installing the cap now because I will bleed the shocks through the cartridge when I fill them with oil. If you want to bleed them through the cap that works too, just install the cartridge at this point instead.
Next we’ll fill the shock bodies with oil and bleed them out. Make sure you let any air bubbles in the oil rise up and dissipate before you try to bleed them.
Wrap the shock body with a napkin or paper towel and fill the shocks with oil until the oil just touches the threads inside the body for the shock cartridge. Wrapping the shock body with a paper towel keeps the oil from running down all over the shock body when you bleed them.
Pull the shock shaft all the way out until the shock piston bottoms out on the cartridge. Then thread the cartridge into the body a couple turns only.
Now compress the shock shaft until the bump stop bottoms out on the cartridge. Any excess oil should flow out through the gaps in the threads at this point. Once the shock shaft is bottomed out, thread the cartridge into the shock body with your fingers and tighten it up by hand. Make sure the shock shaft stays fully compressed as you thread the cartridge into place. Remove the paper towel and wipe up all excess oil. Now tighten the shock cartridge up using a pair of pliers on the plastic flats of the cartridge and holding the shock body with your hand. If you start cycling the shock before you tighten the cartridge up all the way, you may get air bubbles inside the shock body and you’ll have to start all over again.
Last thing you need to do is install the supplied rubber bushings into the top cap.
Here you can see them mounted up to an SWX AX10 build.
Following these tips should help you get the most out of your shocks and keep you out on the rocks practicing, instead of at the work bench rebuilding.
EXO Terra Buggy
King of the Hammers
New To R/C?
VIDEO OF THE WEEK