Frequently Asked Questions
edited by Chris Barthelson
Last Updated: July 12, 2005
Q, how much does one of these beasts cost to build?
A, The price can range from about $700-$1500 for a fully operational tank, depending on what track system, motors, speed control, paintball gun etc, you decide to use.
Q, how much do they cost to buy from a supplier?
A, the prices start at $699 for a F.O.A tiger 1 hull and work their way up to $10,000 for a battle ready, fully operation paintball tank.
Q, how much do these things weigh?
A, usually between 70-150 lbs depending on the materials you build it from, and what size batteries you use.
Q, how fast do they go, and what’s the performance like?
A, 12v EV warrior motors with a 9/1 transmission and a 4” drive wheel gives you about 3-4 MPH. They also give you a lot of torque for climbing hills (40-450), and for full skid turning in thick grass, mud, bushes… Anything really.
Q, is it hard to build one of these, and what sort of tools do I need?
A, if you plan it out right from the beginning no, they are not hard to build. Even if you get stuck you can always ask the mailing list for advice. The tools needed are pretty common, and any woodworker should have sufficient tools. Just the basics, like various saws (hand and powered), drills, & clamps, things like that.
Q, where can I buy scale drawings/plans?
A, www.afvnews.org has a large selection of 1:35 and 1:48 scale drawings by George R. Bradford that sell for $2 each. You could also buy a 1:35 plastic model, this gives you an overall view of every detail, and then all you need to do is scale it straight from the model. As for plans that instruct you how to install your motors, wiring, transmission, you can’t buy them, but this website has pages of tanks that have been built by the members. You can look through them to get a pretty good idea.
Q, how do I get started building one of these behemoths?
A, the first thing you should do is join the mailing list, so you can ask questions and be given advice. Then you should go to the how-to section and read “first steps in constructing an r/c combat vehicle”.
Q, what tank should I build?
A, this is entirely up to you, as long as it’s within the rules. For a first vehicle I would suggest something boxy, and not to low profile. It just makes it easier to build.
Q, what are the best motors to get for my tank?
A, this depends on how heavy it is, how long the tracks are (contact length), and how big your drive sprockets are. It’s been said that 400 in/lbs (after gear reduction) is a good amount of torque for an average size tank hoping to perform full skid turns. You will also want at least 250 RPM, (after reduction) which will give you a good top speed (3-5 MPH).
Q, what type of speed control should I get for my tank?
A, again this is up to you. Things that should help you decide are, how many amps your motor draw, wether or not you want proportional speed, and the size of your wallet. You should also see “speed controls” and “speed control review” in the how-to section.
Q, what sort of batteries do these things use?
SLA (sealed lead acid) batteries are used because they don’t leak and can be placed on their side or upside down, which is good because of the sometimes limited space in the hull. Most of the tanks built to date use between 17Ahs and 26Ahs.
Q, how long do the batteries last?
A, with two EV warriors I can completely drain a 17Ah battery in 10 minutes, but if I drive more conservatively that same battery can last up to ½ an hour. The transmission you choose also plays a huge part in longevity of the battery life. Typically you want to be able to drive around for at least ½ an hour before you must replace/recharge your batteries.
Q, what size fuse should I use?
A, you want the max amperage of the fuse to be about two thirds of the total stall current of the motors. For example, a 12v EV warrior pulls 99.2 amps at stall, so the fuse needs to be at least 60 amps. You should also use slow blow fuses (car audio) because they can handle sudden spikes of stall current (turning), but still blow if your tracks lock up.
Q, are the tracks hard to build?
A, it depends on what tracks you are trying to build. For example, with plastic conveyor tracks it is simply a matter of adjusting the length and then installing them. Whereas TTS tracks are a lot more involved requiring you to cut the cleats, cut the belt, & glue and nail (or rivet) the cleats on.
Q, how do I make the tracks?
See the how-to section for a complete guide.
Q, how many channels does my transmitter need?
A, your transmitter will need at least 4 channels for a turretless tank, and 5 channels for a turreted tank. 2 for driving, forward reverse and turning, 2 for the gun, fire and elevate, and 1 more for rotating the turret.
Q how fast does my turret need to be?
A, you want your turret to be between 4.5 RPM and 12 RPM (13 seconds-5 seconds a rotation). Slower speeds give you more accuracy, whilst the faster speeds reduce accuracy. The ideal setup would be to use proportional speed so you can still have the faster speeds but also have the slower speeds for slight adjustments.
Q, how big should my Co2 bottle be?
A, it depends on how much free space you have in your turret. If you can fit a 20 oz bottle use it, but if not you will want at least 4 oz.
Q, how do you fire the gun?
A, most battlers use a servo connected to the markers trigger to fire their gun, and some use a door lock actuator (car central locking) to fire theirs.
Q, what sort of range does the paintball gun have?
You could easily shoot 150-180 feet but you’re unlikely to hit anything. 10-70 feet is a more realistic distance to be hitting targets.
Q, how long do the battles go for?
A, they usually last for 1 hour.
Q, how many tanks participate?
A, the largest battle held to date (Essex Homecoming Battle #2) had a total of 7 tanks, 2 supply vehicles, & 2 artillery pieces.
Q, how do I get my tank designated?
A, you must have finished at least to the point where the hull is mobile under its own power. When you get this far you announce it on the mailing list and you will receive an official designation number.
Q, why does it have to be a tank that was produced?
A, this rule was made to keep all the “star wars” tanks and “ridiculous” prototypes out, it’s not fun if you opponent has a tank that can fly, with 5 turrets, and a chain saw mounted to the front (although it would be cool to see). Even after eliminating all the prototype tanks you still have 100 years (literally hundreds) of production tanks to choose from.
Q, why is the speed of the tanks not limited?
A, because at the moment no one has come up with a motor/transmission setup that needs to be limited. Even when someone does, by the next battle everyone will have that same setup.