Tank Mobility Guide

ACF can be tricky to get into if you aren't familiar with building vehicles. Thankfully, once you do it a few times, it'll become second nature. This particular page will detail how to get your first tank moving as well as explain engines and gearboxes a little.

Absolute Basics

At the very minimum, you'll want an engine, a gearbox, and fuel for the engine to consume to give power.

Not sure what to use? Give the engine and gearbox pages a view!

First Moving Tank

You'll want a few tools in order to follow this really basic guide:

• Advanced Duplicator 2
• Multi-Parent Tool
• Axis/Ballsocket Center

1. First, you'll want to take a large plate, preferably long in one direction, and freeze it in the air. Make sure to set the weight to about 500.
2. Next, find your spray button and put it on the floor below you. Do you know which way is "up" on your spray? That's north when it's on the ground!
3. Once you find that, rotate that big plate you just spawned so that it's longest towards north.
4. Now, you'll need wheels. Spawn a couple of the same wheel, and put them in the shape of the tracks you want on your tank. Make sure you have a pair of wheels near the back that don't touch the ground that you can later link to with the gearboxes!
5. For the sake of being extremely basic and accessible, we'll just use the Axis Center tool to attach them to the plate. This will still be loose enough to be a form of suspension. Next, take the Adv Ballsocket Tool, and go through X/Y/Z and put -0.01 and 0.01 in the Min and Max fields respectively. It should be X Min -0.01 and X Max 0.01, and the same for Y and Z. Turn on Free Movement and Nocollide. Now, going from those rear elevated wheels to each other wheel and put a ballsocket between them. This makes it so when you apply power to those rear wheels, all of the other wheels will spin too.

Quick Note: Here is where things get interesting! In the most basic form of a tank, you have an engine, a gearbox, and fuel for the engine. For this guide, we'll use a medium V8 Diesel engine, a 20x40x40 fuel tank with diesel in it, a 6-Speed Medium Straight Gearbox, and 2 Small Differentials. Take out the ACF Menu tool and spawn each of these!

6. Take the engine and put it at the front of the tank, then take the straight gearbox and put the big part of the gearbox in front of the little circle on the engine. Now, at the back and next to those previously mentioned separated wheels, put the 2 differentials next to them, on the inside of the tank where the sides of the T can face them, and the middle can face the straight gearbox.
7. Put the fuel somewhere on the tank where it's not in the way of anything.
8. Link the engine to the Straight gearbox, then the Straight gearbox to the 2 differentials, and then the differentials to the wheel they are next to. Then, link the engine to the fuel.

Here comes the part where we parent all of this stuff to the vehicle, which makes anything attached without having any physics. It's crucial that you do not weld any of these components before parenting, or otherwise it won't behave the way we need it to.

9. Now, use the Multi-Parent tool to parent all of these new ACF components to the plate. Make sure that you don't parent them to anything else by mistake!

Another Quick Note: Right here is a crucial part of building vehicles, the testing! It is a really bad idea to unfreeze the vehicle you are working on to test it. Thankfully, we have a tool called Advanced Duplicator 2 which can let us spawn a whole other copy of the vehicle you just made, and even save it for later use. Take this tool out, right click the baseplate of the vehicle, and then paste this new ghost somewhere nearby. If all went well, you can unfreeze this new copy, and the vehicle should fall down with all of the ACF components firmly attached, with the wheels spinning freely.

10. With the now unfrozen copy, you'll want to try to turn on the engine and make it move the tank. Go to the wire tab, spawn a button with an On value of 100, and wire Active and Throttle to the engine. Active only needs to be 1, but 100 will work just fine, and Throttle is 0-100 so we're giving it full throttle. If all of the other steps were followed correctly, the tank should start moving in any manner.

Adjusting

If the vehicle is spinning, that means one of the differentials is reversed. This is easily fixed by going into the ACF Menu tool and picking exactly the same differential size and type, and just making the final drive -1, then updating the differential on the side it's rotating to. As of writing, there is a nuisance in regards to updating gearboxes of any kind, they will get set to Gear 0, or Neutral. You may have noticed that it won't give you power any more through that side, which means you need to use another button and wire it to Shift Up, then press it.

Crash Course on Gearbox Ratios

All ratios can be applied as a multiplier to the engine's RPM as well as torque. Take for instance, an engine running at 2400 RPM, and it is feeding through a gearbox at gear 3, which has a ratio of 0.09, and a final drive of 0.75. That gearbox is then feeding into a differential which has a final drive of 1, so it is irrelevant. So, the drivetrain's output is 2400 * 0.09 * 0.75 giving us an output RPM of 162. With these gear reductions, torque is also going up, allowing us to move heavier weights, which is important when it comes to armored vehicles.

A good basis to work from is to keep all final drives at 1, and on your main gearbox, start small for gears, like 0.03, 0.06, 0.09, 0.12, 0.15, and -0.04. Typically, in some vehicles at least, the last gear is reserved for a reverse gear. If you are feeling adventurous, you can instead use that last gear as one more forward gear, and instead of normal differentials, use Transfer Cases (which are special 2-speed gearboxes perfect for this application as well as a high/low range gearbox) to have full forward and reverse speeds.

11. From here, you've probably figured out that you can make something go forward. But how do you go backwards, left, and right? For all of this, you'll want to move away from buttons. Spawn a seat, any seat, and go to the wire tab and spawn a Pod Controller then link it to the seat. This nifty little device lets you easily tap into the controls that it outputs. You'll also want a Constant Value with 100 as one of the outputs, a Wire Gate set to Multiply, and 2 Wire Gates set to Logic (Or).

12. For the engine, get rid of the Active and Throttle wires, then wire Active to Active from the pod controller, and Throttle to Out from the Multiply gate. Wire A on the Multiply gate to the Constant Value with 100, and then B on the same gate to W from the pod controller. Next, for the left differential, take ONE of the Or gates and wire Brake and Clutch to Out from that Or gate. Then, wire A to A on the pod controller, and B to S on the pod controller. Mostly the same for the right differential, except you are going to wire A to D on the pod controller as opposed to A (A is left, D is right).

13. You'll probably want to control the gears on the main gearbox. For now, you can get by with R for Shift Up and F for Shift Down, as these won't interfere with shooting.

14. Now, you can parent all of these new bits to the plate you parented everything to earlier. If everything went well, you should now be able to sit in the seat, press W, and drive around, and get to higher speeds by shifting up.

Overall your controls should have turned out to be like this:

• W for Gas
• S for Brakes
• A/D for steering left/right
• R to shift up
• F to shift down

Important note regarding brakes: brake power has received several changes since this was last written, and as of writing it now has no limits as it scales differently. Generally for cars up to 100 may be the most someone will ever need, but for tank tracks with the extra rotating mass of the other wheels you'll need higher, it is not uncommon to see 300 or higher.

In the future, you may want more precision with placing the wheels and constraining them, which is where tools such as Precision Alignment or the Precision Tool come in.

Next: Turret Assembly Guide