TF2 Paintball Sentry Lv.1

Introduction: TF2 Paintball Sentry Lv.1

About: If you need to contact me, just send me a fb message

I've been working on making a Sentry Lv1 from Team Fortress Two for the last little while, after I decided that the Portal turret can in no way support a paintball gun. The sentry will have at least 3 different modes of tracking: Manual, Disparity Mapping(distance mapping), and Color Tracking.

I will be showing step by step how I fabricated the sentry using my Ultimaker 2 3D printer and the Autodesk Inventor(student) software.
However, I will not include any of the programming files or 3d model files since I plan to sell it as soon as I am happy with the final result.

The steps include:
-Modeling and Printing

-Assembly and Painting

-Mechanical and Electrical Parts

Step 1: Modeling in Inventor

I used Autodesk Inventor to model my Turret. However, you have to keep in mind that the whole build will not fit onto a 3D printer, so it will need to be split up into pieces, and screw holes to assemble them together will need to be added. I used 0.3175cm holes for my screw holes and #6 machine screws to go with it. You will also need to think about how it will print out on your printer, try giving each piece a large flat surface to print on and as little overhangs as possible so the final piece will look top notch.

I chose to print at 0.1mm layer height since 0.025mm would take literally forever. At 0.1mm, each piece takes at least 24hrs to print out, so you might want to choose 0.2mm instead.

Important note: 0.15mm for a tight fit on your parts and 0.3 or 0.4mm for a loose fit.

Step 2: Assembly and Painting

Now that everything is printed out, go ahead and assemble it together and spray on a few coats of Rustoleum Primer. After the primer has dried, use a large flat brush to paint on whatever color you wish. If there are multiple colors involved and you do not have a duel head printer, use Frog Tape for a nice, crisp color transition.

After it has been painted and primed, use Krylon Crystal Clear Acrylic Coating to seal in the acrylic paint to give it a high gloss finish, and to keep the paint from pealing off.

Update 12-5-14:
-I found it useful to sand the model down with wet sandpaper where the two or more parts meet after you tightly screw them together. It makes the transition hardly noticeable.

-it can be useful to use some sort of epoxy or wood fill if there are any gaps between pieces. Sand it down with wet sand paper after it dries.

-I removed all of the paint and plan to buy an airbrushing kit next time I attempt to paint the model. We will see how well that goes.

Update 12-10-14:

-before airbrushing, rub in wood fill across the print and sand it down with fine grit sand paper. it should feel almost as smooth as injection molded plastic. Repeat as many times as needed. Then start airbrushing on your primer & paint

Step 3: Mechanical and Electrical Parts

I used Stepper motors and a Raspberry Pi to control my turret. You might want to use a switch so the pi knows where the Home setting is(forward facing) when it turns off and on, so it always starts where you want it to.

The gun and hopper itself is fit into the chamber basically side to side instead of a hopper being on top of the gun. An electrohopper feeds balls into a tube, and those balls travel into the ball feed of the gun. That is the theory at least. I'll update this when I find out how well it works in practice

That's about it. it's not too complicated. Just make or find some good tracking software and you got yourself a turret. Best of luck to anyone who wishes to make one, or message me if you wish to buy one from me after it is completed.



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11 Discussions

i want to buy one for how much

Hmm, I'm wondering about the feasibility of selling it without a cease and desist from Valve. Unless they don't care about that sort of thing.

1 reply

Someone sold a few full sized Portal turrets and received a lot of media attention. I plan to make one for me, and like two to sell. I'm sure they won't mind, just like the Portal ones.


3 years ago

interesting light weight concept. I used a motion detecting camera, with tracking and control, added perimeter staging and triggering. Mounted on metal frame for stability and durability. This was several years ago. Programming has become much easier and better to customize. Are you able to print a flexible material like what most paintball mask are made of?

3 replies

Motion detection will not work with my design since the cameras are attached to the gun box and always moving. I plan to use a personalized disparity map to map out the field, and then aim at any non-friendly object that moves onto the stage. Can you define perimeter staging? I never heard the term before. and yeah, I can print in flexible materials that are simular to rubber.

The motion detector is mounted to the camera and weapon system, so all is in motion, constant pan. Also could mount peripheral motion detectors for more advanced system. This is where perimeter staging comes in ; if something is detected with in a certain range, the system will shorten its pan from 180 to 45 degrees. When the detected target is closer it locks in, follows, shoots at closer range or, pending on your set up. My friend had a high end security system that we used which was set to take pictures at closer range, we modified to trigger the paintball gun. Final build was 2 ft by 2 ft by 2ft and about 20 lbs.

Nice. I have been considering building a level 2 or 3 one out of wood that shoots either rubber bands or nerf darts. It is unlikely I will have the time to do it though. Possibly based on this:

1 reply

I was thinking about Level 2 or 3, but the level one is just too adorable to me to not do, lol. also, It would be insane to have to disassemble the whole thing to be able to take it anywhere. also, unless you have a CNC machine, you won't be able to make it out of wood.

In the future, I think I will use airbrushing.

I'm going to stop painting the parts for now until I can test airbrushing on one of them. I'll reprint what I have so far if I need to.