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Building the VAJRA

Vajra [vuhj-ruh] noun: thunderbolt. Cause when lightning strikes... thunder is all you hear.

The Vajra is an electric racing truck based off the Avante, but has a wheelbase that is 15mm longer. This racer is a shaft driven 4WD system featuring new front and rear ball differentials. There are access hatches on both the front and rear gearboxes to allow gear changes without detaching them from the chassis. Four wheel independent double wishbone suspension is equipped with upper turnbuckles, lightweight lower arms, aluminum front uprights, CVA oil dampers, carbon fiber damper stays and carbon fiber steering plate with ball bearings. All this to enhance durability and ensure superb off-road performance.

A few other highlights in this kit are the 26 ball bearings, carbon fiber throughout, 25T GT-tuned motor and a bonus part of limited edition stickers.

Items Required:

2 Channel Transmitter and Receiver

Steering Servo

Electronic Speed Controller (TEU-104BK suggested)

7.2V Battery and Charger

Tools

Paint (PS Spray Cans)

Let's get this build going. I will go through each step and throw out pointers as I go.

Box Art and Unpacking

Bonus Stickers

Key Extras: Carbon Fiber, 25T GT-Tuned Motor and Ball Bearings

On each step I like to gather all the parts for that step. So I'll get out the big pieces and then I use the manual to figure out which screws and nuts I need because the pictures shown are the actual size. Also you will notice a little tube in the manual pointing to different parts. The tube is where you put grease which is included in the kit.

Step #1

Step #2

There is a note in the manual about sealing the edges of the carbon fiber plates with instant cement. This is optional, but helps protect the carbon fiber from chipping.

Step #3

In Step 4 you will notice a comment about removing flash from a plastic part. This should be done as needed to remove flash with a sharp blade (caution).

Step #4

Step #5

Step #6

Step #7

This step requires many parts, so be sure to gather them all up. Also, I use a small flat head screw driver to help me apply the grease to the various parts. My suggestion when placing the steel balls is to place the differential spur gear on part BA22. Then use the screw driver to place a small amount of grease in each hole. Then drop in the steel balls and use the screw driver to move them into place. And again, use the driver to place a small dap of grease on top of each steel ball, then place BA24 on top.

Step #8

You will note in Step 8 is a comment about tightening down the diff screw (BA19). You can do this two ways. First is the way shown here, where you keep both sides still and move the center gear forward to tighten the screw. The second way is in step 7 where you can use a flat head screw driver on the head of the diff screw and hold the other side to screw down.

In steps 9 and 10 you are putting together the front and rear gears and coating with grease. Whenever I am dealing with gears and grease, I always put a ton on. It will protect the gears and help with performance. Note you are also detaching the diff joints.

Step #9

Step #10

Step #11

Step #12

Note the cones are threaded, so feed the screws through the hole and tighten down the first one. Then put on the arm and thread on the next until tight.

Step #13

Step #14

Step #15

Optional: seal the top deck with instant cement.

Step #16

Note on this step there is a lip/slot in the plastic cover. Make sure the motor mount goes in there.

Step #17

The manual calls out for use of gel type threadlock (sold separately). I used some Tamiya blue tubed threadlock I had from a previous build. Optional: seal the upright carbon fiber.

Step #18

Step #19

Another one with lots of parts, so make sure you get them all.

Step #20

Step #21

Step #22

There is note in the bottom left of Step 22 about which way to turn turnbuckles. This is for when you need to adjust the camber on the rear or the alignment on the front.

Step #23

Step #24

Just like 19, get all the parts together. Make sure you use locktight on those BB4 screws.

Step #25

Note the grease points just like in Step 19 and 24.

Step #26

Once again, lots of parts.

Step #27

On this step there is a correction. Instead of X2 and V2, you use X1 and V1. Also, don't forget when you are doing the front dampeners to get that V11 spacer in there.

Step #28

Only tid-bit I can give you is to move the piston up and down slowly and then let them sit for a period of time to allow the air to get out.

This kit comes with damper oil #600, which is right in the middle between soft and hard. How thick or thin the oil is will determine hard or soft.

Step #29

You will note on this step it calls out for tension adjustment spacers. They are optional and I wouldn't put them on until the vehicle is complete and you can fine tune the suspension. Also note there are three different holes on the upright for the damper mounts. I would start in the middle. If you want stiffer, then move to the outside holes. Softer, move in. Same goes for the front upright.

Step #30

Optional: seal the upright.

Step #31

Side note: After completing I moved the damper mount to the middle hole.

Step #32

This is to get the servo all set up.

Step #33

Step #34

This is to get the servo all set up.

Step #35

Note with wheels go with which tire. It does matter.

Step #36

Step #37

Chassis Done: Now onto the body.

Step #38

This is where you cut out the body and put in the holes for the mounts. I am going to wait to do this until after I'm done painting, but you can do before.

Step #39

The first part is to wash the inside of the body to remove any oil or release agent from the mold. You just need warm water and mild dish soap. I use a paper towel to wash with so I don't scratch the body. After you rinse it thoroughly, be sure to towel drive with either a paper towel or soft cloth that won't leave lint. If there is any lint you can just brush it out once the body is fully dry. Let the body dry overnight to make sure there isn't any moisture left. Next comes masking, you'll need to mask the windows so they don't get any paint on them.

Once you have picked your color, go ahead and spray it on. Move the can in even strokes across the inside of the body. Your spray can should be about 8 to 10 inches away and don't worry about getting paint on the outside. There is a protective film that we will peel off after we are done painting. Let the body dry overnight to let the paint fully cure.

Next comes the backing. This can be any color, but is typically either white or black. I choose white to brighten up my silver color. I then let it dry for a day and then peel off the masking for the last paint step.

Last is the windows. You have three choices here.

Leave them clear.
Paint them with smoke to give a tinted look.
Paint them black so nothing is seen.

I chose to tint them.

This is when I peel off the film, cut out the body and ream the holes for the mounting posts. You will notice that I didn't follow the cut out for the front wells. I'll address that later.

Step #40 Stickers

I'm going to be using a combination of the two sticker sheets. Which is one of the nice things about having both... you can really customize. The stickers are not pre-cut, so you have to cut them out. This can be done with either some scissors or a razor blade or both.

Step #41

Mount wing and aluminum glass tape.

Step #42 Finished!

Back to the front wheel wells. I liked the look of the wells as is, so I was hoping to cheat, but after mounting and test running, I found you have to cut the wells back so the wheels don't hit the body.

More build action coming soon...