When we first looked at this tank, we thought it was pretty cool. The sides are unpainted 1/2″ (12mm) plywood, so it is not flashy. The dimensions came from Google-fu-ing the heck out of the WWII Hetzer and scaling them to 1:6. What knocks our socks off is how much [Bret Tallent] made use of parts you would find in a hardware store or bicycle shop. He uses twin motors from electric bikes, and the wheels look like replacement shopping cart wheels. The best part is the treads, which are dozens of hinges fastened with pairs of bolts and nylon-insert nuts. Something is reassuring about knowing that a repair to your baby is no further than a bike ride.
We don’t know what started [Bret] on his path to sidewalk superiority, but we suspect he is cooped up like the rest of us and looking to express himself. Mini-Hetzer is not licensed by Power Wheels and never will be, so it probably won’t turn into a business anytime soon. There is a complete gallery starting with an empty plywood base, and the pictures tell the story of how this yard Jäger got to this point. There are plans to add a paintball gun and streaming video, so we’d advise that you don’t mess with the jack-o-lanterns on his block this year. Give his gallery a view and see if you don’t become inspired to cobble something clever from the hardware store too. Then, tell us about it.
What’s more fun, driving RC cars around on rugged terrain, or having a paintball battle? How about doing both at the same time by making an RC controlled, paintball firing tank? [Nate] from the King of Random YouTube channel did just that by mounting a modified paintball gun to a stripped-down RC car, adding an RC trigger to remotely fire the gun, and covering it all in EVA foam armor in the shape of a tank. And then he did it again so that he’d have someone to battle against.
He walks through the full build in the first video below, but here are some things that stood out for us. It took some fiddling to get a servo to pull the gun trigger but how could he remotely control the servo? For that, he took over the car’s RC receiver signal for controlling audio and made it turn on and off the servo instead. We also like his use of aluminum bar. This stuff is available in the hardware section at stores like Home Depot and is easy to cut and bend. You can see it used here for mounting Wimshurst machine parts to a bicycle, and in this hack, [Nate] used it to mount the paintball gun rigidly to the car frame. He did surprise us when he used rivets instead of nuts and bolts to hold the frame together. That’s not something you see often, and it worked great.
As we said, he made two of them. In the second video below, watch the tanks in action as [Nate] and fellow YouTuber [Stuart Edge] have a tank battle in the desert.
It seems as though [Nathan] has taken some serious inspiration from the Warthog. The iconic armored buggy from Halo video games has a turret mounted to the roof. Although [Nathan]’s buggy only shoots paintballs from its turret.
Mounting paintball markers (guns) to various objects such as vehicles, robots, or other machines isn’t quite as straightforward as it seems. Vibrations from anything can transfer through a clamping system and cause paintballs to break. This, of course, inhibits the functionality of the marker and is a messy cleanup to boot. Then there has to be a way to fire the paintballs, which is usually handled by soldering to the electrical connections in the marker. And the entire rig has to stand up to the normal jostling and sudden turns from the buggy.
[Nathan] has solved these problems first by creating a custom fast-change mount that allows any malfunctioning markers to be changed rapidly. The electronic firing mechanism is handled by an ATtiny microcontroller and there is a custom electrical connection that is automatically made when the marker is bolted to the mount.
The new system allows markers to be changed in about 30 seconds, much better than any other system. Maybe in the future [Nathan] can upgrade the buggy’s turret to accommodate a paintball minigun.
We’ve seen quite a few automated paintball marker systems over the years. Generally it’s the same story – a motion detection system used to target and fire upon the opposing team, prowlers, spouses, etc. [Waterloo Labs] decided to take a slightly different approach, and create a system that intentionally misses its target. Paintball Picasso uses a pair of Tippmann A-5 paintball markers to draw an outline around the person in its sights. This is a rather safe project for [Waterloo Labs], considering their previous adventures in car surfing.
The Paintball Picasso system uses a webcam to capture an image of a willing test subject. Picasso then processes the image. The human outline is plotted on a 50×50 grid of paintball pixels. Then the real fun begins. Paintball Picasso uses a National Instruments myRIO to command two paintball markers to simultaneously fire. The markers are fitted with high torque R/C style servos for pan and tilt. At 10 rounds per second the markers quickly draw the human outline. The test subject walks away slightly splattered, but otherwise unscathed. With a matrix of 2500 points, [Waterloo Labs] has enough resolution to draw some basic logos.
We liked the mounting system [Waterloo Labs] created for the markers. Using a mix of 3D printed parts, Lego Tetrix, 80/20 aluminum extrusion, and ball bearings, they fashioned a mount that moved smoothly enough for R/C servos to actuate, yet was strong enough to withstand the kick of firing. We’d love to see the servos swapped for stepper motors and belt drives. While open loop, stepper motors would afford more accuracy and a longer life than PWM driven R/C servos.
[Spider!]’s contribution to the pantheon of paintball markers is the SMAC: a unique revision to one of Airgun Design’s ever-popular Automags. We needed our tipster, [Russell] to provide some context on the Automag’s evolution, because the brand has served as a popular hacking platform for nearly 20 years. The most frequent is a “Pneumag” modification, which converts the original, fully-mechanical trigger pull into a version where the trigger actuates a pneumatic cylinder to fire the gun.
According to [Russell], the Pneumag’s trigger must completely release between each shot to properly recharge the firing chamber. Without a full release, the gun can load extra balls into the barrel and lead to gloppy consequences. Electronic controls solve this problem, but [Spider!] favored an analog solution that captured a “less is more” mentality over a pre-fab microcontroller board. He built the circuit around a 556 timer used as a delayed re-trigger, but with a few modifications.
Swing by [Spider!]’s forum post for additional details, a cluster of pictures and a bill of materials. Microcontroller alternatives? We’ve got you covered.
If you’ve ever worked with air tools outside of a shop setting, you know that lugging the air hose around can get more and more annoying the further away you are from the compressor. [headsplosive] posted a video (embedded after the break) showing how to go mobile with your air tools.
Air tanks made for paintball are high-pressure in a tiny space, and make a very convenient energy source. In this case, [headsplosive] used a 68 cubic inch, carbon fiber wrapped tank rated at 4500psi. The normal regulator only steps that pressure down to 800psi, so he added a second regulator to hit the 120-140psi that air tools need. He then attached a ‘remote line’, or a coiled high-pressure hose, and added a standard air tool coupler at the end.
The yield is pretty impressive. With a half-charge of the tank, he managed to drive 100 two-inch nails. [headsplosive] has a scuba tank handy, and uses that to recharge the paintball tank. He estimates a scuba tank will last you about 2000 shots from a nailer, and only costs about $7.50 to recharge. Not bad at all. We can’t help but wonder how long you’d get out of an air-powered cutoff wheel, or even a hammer drill. While the parts aren’t terribly cheap unless you buy them used, it will still pay for itself in convenience if you have the need.