Making an “Aliens” Motion Tracker – Part 1

Making an “Aliens” Motion Tracker – Part 1

This is a step-by-step build of my 3D printed M314 ‘Aliens’ Motion Tracker. While it may not be entirely useful for anyone who isn’t putting one of those together, it may be of interest to people who like Aliens, or you may want to build your own motion tracker. Although mine comes with an assembly instruction manual, I didn’t follow that when I did this, so some steps may be different to those in the manual, however, it ends up at the same place!

You can download the files to print this yourself from Thingiverse here which includes the graphics and the instruction manual.

1: Check your parts.

When I send a kit out, I always tick off the parts against the parts list in the manual, but as with all kits I think it’s good to make sure you know you’ve got everything, what it looks like, etc.

Motion Tracker Build 1


2: Cleaning and sanding (the really boring bit)

I admit, I hate this part. Cleaning the parts, trimming the flashing down and sanding them down to the finish you want. This is extremely important with any kit, but with a 3D printed kit it can make a lo of difference. If you want a really “moulded smooth” finish, you could at this stage do a LOT of sanding and some filling, it’s up to you!

Motion Tracker Build 2


3: Installing the ‘monitor’ mount

First thing to do is put in the mounting connector block. I did this as a separate part because the weakest part of a 3D print is laterally along the strata (the lines you can see). Under enough pressure they can pop apart, and so, for the connector I wanted to make sure that it made the strongest connection possible. That’s why the actually connector black is printed as a separate piece.

To get it in, just sand down the matching hole in the side of the lower body. Do a couple of test fits – it’s supposed to be very tight – and when you’re happy, glue it in place with your strongest glue. I use superglue, and that works fine. For extra strength I use gorilla glue around the overlapping ‘foot’ on the inside, as you can see in the second picture here.

Motion Tracker Build 3

Motion Tracker Build 4


4: Assemble the body sections together

Sandwich the body spacer between the upper and lower body sections, line up the four screw holes (two on the top at the back and two underneath at the front) and screw together with 3mm screws. You can optionally add glue at this stage too.

Motion Tracker Build 5


5: Assemble and attach the ‘pump motor’ bit

The odd little thing that goes on the front is often called the ‘pump motor part’, I guess that’s what the thing was they used in the actual Motion Tracker build originally. Glue the little stick part to the front of it first, then glue two of the supplied pegs into the mounting holes. These aren’t essential, they are mostly there to help you get it sitting in the right place since they match up with the holes in the body, but they also do add some strength. Then glue the part into place on the body.

Motion Tracker Build 6


6: Attach the numberpad block

This will be the part that you attach the number keypad to. Feed a 3mm screw through the hole in the middle and screw/glue it into place on the body, making sure to get it straight.

Motion Tracker Build 7

7: Assemble and attach the little thing with the round things on

I don’t know hat this bit is, I think it’s some sort of button or switch panel, but for our purposes it’s the bit that will ultimately hold a wire that will go to the pump motor section later on! Glue on the little cone shaped nozzle on the side, then glue in two of the mounting pegs and glue it to the body under the numberpad block.

Motion Tracker Build 8


8: Assemble the handles

This is where it starts feeling more like the ‘tracker. one side of the handle has screw holes, align the screws, then glue the seams and screw in the 3mm screws to join the halves together. Before you assemble it, trim out the supports and any stray filament sections from inside the trigger housing. It may be good at this point to test fit the trigger. If you’re hand painting it you can always glue in the trigger at this stage, but if you’re spraying it all (like I did here) then you need to leave the trigger out for adding in later since ti’s black and the handle is green – but it can be a pain in the neck to fit in later unless you make sure it fits at this stage!

Motion Tracker Build 9

Motion Tracker Build 10 Motion Tracker Build 11


9: Attach the handle to the body.

Pretty simple step, there’s triangular and circular sockets that line up with the relevant bits on the handle, glue is optional here. There’s two screw holes at the base of the handle, use long 3mm screws to secure it to the body.

Motion Tracker Build 12 Motion Tracker Build 13


10: Assemble the bottom cap of the body.

Use a short 3mm screw and glue to attach the ‘adjustment knob’ to the bottom of the body cap, then put this part aside for now. You can screw it onto the body at this point if you’re hand painting it, but since the cap is black and the body is green, I left them separate for now.

Motion Tracker Build 14


And now you have most of the basic body assembled. The remaining assembly continues in part 2 here…

Motion Tracker Build 15

Go on already, continue to part 2!