The Build – Part 7
In Step 7 we will be putting together the 2 halves of the chassis as well as installing the servo and brushless motor. There are a few tricky spots here to pay attention to so make sure you read the notes for each step.
In a couple of the steps you will be advised NOT to tighten the screws all the way down. Keep an eye on these steps…it will make building the XS SO much easier.
With some kits you can continue the build without electronics; not this one. You will need the servo and motor, and I would HIGHLY suggest turning everything on and centering the servo now. If it is not centered when installed in the truck, you can do it without removing it but it is a bit of a pain.
Pay close attention to the step where we piece the two chassis halves together with the steering. It is a bit tricky to line up the steering posts so take your time. If you don’t line them up you’ll end up with severly bound steering.We start this build with the attachment of the battery box swivel rail. 5 screws and you’re moving on. Next attach the two battery door swivel locks as shown… …followed by the battery door swivel lock locks. These will keep the swivels from swiveling while you’re driving. Line up the battery door and slide the flexible pins in place (one on each side). Press them in farther with the 3x18mm screw, then tighten the screw into place. A quick pre-install look at the powerful Savox SC-1257MG steering servo. I show you this now because once the XS is completely built you won’t see the servo again. This is also a good time to center the servo (see the Build Notes above for this step). Slide the servo into place and secure with the four 3x12mm screws. Not the direction of the output shaft during the install. Build the drag link. No exact length was given so I threaded the ballcups in until they touched. Thread the 3x12mm screw through the open-ended ballcup and into the servo arm. Make sure you choose the servo arm made for your servo. Attach the servo arm to the servo as shown. Build the bellcrank link as shown. Attach the servo saver arm assembly and the opposite steering arm to the bellcrank link. HPI has graciously built the servo saver for us. One less step to worry about. Attach the upper steering support to the chassis as shown. Note the direction of the steering post holes (towards the front). Slide the steering assembly into place and attach the drag link to the servo saver. Align the steering posts with the lower mounts and slide the chassis halves together. The lower mount is keyed to the chassis and it’s not the easiest thing to assemble. Take you time and it’ll finally pop into place. Secure with the two 3x12mm screws. Give a quick look to make sure your steering posts have seated in the holes in the mounts. HPI has also pre-assembled the gearbox for us. This will save alot of build time for sure! Take a pair of the locknuts and press them into place on the gearbox as shown. Attach the pinion to the motor. The XS comes with two pinions but since I wanted some stupid speed with this thing, I chose the biggest pinion. Slide the motor into place and, using the pinion-size guide in the manual, secure the motor into place. If you did it right the gear mesh will be automatically set for the gear set you are using. The gooey stuff inside is gear grease…shouldn’t be a problem but just try to keep it in the gearbox. Once you have the motor locked in place, attach the gear cover. Wiggle the gearbox into place and attach it to the chassis plate using the 3 screws as shown. Don’t tighten them down all the way just yet. Drop the cross brace into place. Press a pair of locknuts into the rollbar/carrying handle. Place both sides of the carrying handle into place and, using the two 3x64mm screws, slide them all the way through the chassis (and cross brace) to the other side. Secure the top of the rollbar/carrying handle as shown. You can now go back and tighten the screws for the gearbox you left loose in Step 124.