Tutorials/TNT cannons

A cannon is a mechanism that uses TNT to launch TNT or other Entities. The usefulness in SSP is limited because most cannons can only fire in one direction, making the cannon obsolete once the target is destroyed.

Basic Concepts
A cannon is made using a few main components. These components are the: Wiring is separated into three sections, charge wiring, (Subcatagory Condensation Charge wiring) shot wiring, and other wiring. Explosives are separated into two sections, Charge (Subcateagory Condensation Charge) and Shot.
 * Body, or Housing
 * Wiring
 * Explosives
 * Explosion Housing (Usually water)
 * Mounting Block


 * The Charge is an amount of TNT used to propel the Shot.
 * Ther charge must be housed in water when activated otherwise the cannon will self destruct.
 * If the cannon is to fire and not self destruct, then upon firing the Charge must activate before the Shot activates, because the shot is not housed in water when actived, so it will destroy nearby blocks and injure nearby mobs.
 * Redstone is used to activate every block of TNT in the Charge simultaneously with the exception of Condenser charges, which are discussed in the appropriate section.
 * For maximum range, you want there to be an about 45 degree trajectory but with the least possible amount of matter (blocks) in between the charge and the shot, that way more of the charge's explosion reaches the shot.

--ArkEneru, Cannon Expert

Naming Standards
A cannon's name should give those who read it a complete picture of its function, use, and method of operation. While it is impossible to anticipate every innovation in TNT Cannon technology, most cannons will benefit from using these standards in their formal, if not only, names.


 * The first number in a TNT cannon name designates how many vertical rows of TNT it has for the charge. The example cannon has 1.
 * The next number is the amount of shot TNT, or Shot the TNT cannon has. Again, the example cannon has 1.
 * Next, the number designates how many charge blocks of TNT the cannon has.
 * After that, you list how many repeaters there are, and how much they are set to. E.g. If you have 10 repeaters set to 4, (which by the way is the max setting) you would list R4.10. If there are no repeaters, you would write an M for manual.
 * If there is a condensation system, after you wrote the charge number, write a decimal point, then the amount of condensation charge TNT. If there is no TNT, write 0 instead of a condensation number.
 * The mounting block is designated by a code, 0 for no block, 1 for no block, 2 for full block, 3 for half slab, 4 for ladder, glass pane, or iron bar, 5 for trapdoor, 6 for fence post and pressure plate.
 * If the cannon does something special, like shoot vertically, or does a spread shot, write that after the mounting block code.
 * Then, of course, the nickname of the cannon goes here.

The featured TNT cannon below would be named 114.0R4.4MB2

--ArkEneru

Survival Mode
As discussed in basic concepts, there are many parts of a TNT cannon. This section will show you what you need to build them.

1. Body
 * In SMP, where cannons are most used, the body should be an available material, but should not be totally un-blast resistant. If you are firing at another cannon, the blast resistance of the material is a must. (For more on TNT cannon defenses, look below)
 * Another factor is visibility, which is one commonly overlooked. When making a cannon out of obsidian, it is hard to see redstone, and that can lead to fatal errors. On the other end, when setting up an ambush in the jungle, it is best not to make your cannon out of orange wool or lapis luzilli.

2. Wiring With repeaters is a different story. The maximum amount of time between the charge activating and the shot activating is ten repeaters set to 4. That will also bring you maximum range, will only require one redstone emmiting item, and will require no skill to fire correctly.
 * There are two main sets of wiring in a cannon, the charge wiring which activates the charge, and the shot wiring that activates the shot. Without any repeaters, which can be hard to get, a cannon is designated as manual, with 2 redstone emitting items/blocks, such as buttons. For a manual cannon, the materals are simple, just a redstone wire that connects the charge to a redstone emitting item, and a wire that connects the shot to a redstone emitting item. However, this requires skill so as not to misfire, you must know when to activate each button.

3. Mounting Block
 * !Mounting blocks (described below) are only certain speciall blocks.

4. Explosion Housing
 * Unless its a dry cannon, this must be water.

For cannon practice against player and stationary targets in the heat of the battle, try the server pvp.oc.tc on maps like shroom trip and mideval warfare.

Creative Mode
In creative mode, there is no reason to build a TNT cannon for warfare, but is the optimal mode for testing and developing cannons. --ArkEneru

Cannon Sizes and Special Features
The default definition of cannon size is how many TNT are in the shot or how far it fires. If you are talking about compact cannons, you might be talking about literally the size of the cannon (e.g. How much space it takes up) or if you are talking about cannons meant for mass destruction, you might be talking about the size of the shot. But usually, people mean charge mass. A small cannon, such as a 112.0MM3 Ironwall Anti-Infantry cannon, only has a very small range, and is meant for stopping large amounts of rushing players or mobs (tons of wolves) A medium cannon, such as the 116.0R4.6M2 Scorpion is meant for setting up as a first line seiger, to be set up and aimed at a target such as supplies or a wall while one has arrow cover, or to be set up as an Anti-Archer cannon. A large cannon, such as as the 119.0R4.10M3 Orion is for attacking from a distance, a borderline long range mortar, an Anti-Cannon defense, a second line seiger, and many other uses such as modding for Icarus ammo or a full lobaiming cannon. A sniper cannon, such as the 119.3R4.10M6 Ares, succesor to the Orion, is for a tent line seiger, setting up to shell opponents camp when they can't even see the cannon shelling them, and other über long range tasks such as that. And of course, mass demo cannons, such as the 187.0MM6 Spread Shot Devastator*, which is used to completely multilate any defenses whatsoever. --ArkEneru

Players also like to add features to their cannons including:
 * Multiple shots
 * Semi-automatic/fully-automatic firing and reloading
 * Condenser Charge (Another piece of TNT that explodes, pushing the Charge towards the front of the cannon to concentrate the blast.)
 * Safety features
 * Adjustable Shot Delay, which lets you change the range and trajectory of the cannon.
 * Alternative Ammo
 * Dry Cannon: Building a cannon from explosion-resistant material to simplify design, maintenance, and potentially improve firing distance. See Tutorials/Dry cannon for construction details.
 * Arrows as ammo
 * Cannons that fire in a special direction, such as up or diagonly.
 * Aimable cannons.
 * Spread shot/mass destruction cannons

Limitations

 * Cannon power is limited by the number of TNT blocks in the charge and their distance from the shot being propelled. Too many TNT blocks detonating at once will cause an out of memory error and crash the game.  With the standard 1.2 GB of memory allocated to Minecraft, the limit is near 500 blocks of TNT.
 * Range is limited by the speed the shot leaves the cannon and the fuse delay on the shot. The maximum fuse delay is 4 seconds, which is the time from charge activation to charge detonation.  This means that the shot can fly for a maximum of 4 seconds before detonating.  This limit does not apply to shots that don't need to be activated, such as minecarts.

Following the 1.0 Minecraft release, making the practically appealing TNT Cannons is now more difficult, since activated TNT entity is no longer affected by water current, thus the propelling power of TNT blocks used as fuse cannot be condensed effectively by that means. However, if a 3rd set of TNT is used, a single TNT block activated slightly before the main charge, can condense the charge. This 3rd set would need to be place far enough away to not affect the TNT block to be launched.

One-Button Middle Range Cannon
The following is a simple cannon that covers automatic delay. Please see this video tutorial if you need additional help.

As of 1.0, this cannon has decreased power. It is now a functional anti chargeing cannon, but not a ranged tool.

One-Button Cannon with a Minecart used as delay
This cannon is semi-automatic, once you press the button, it not only lights up the "boosters" but also sends a minecart around the cannon that triggers a detector rail, which lights up the charge. Saves redstone, but takes a lot of iron (However, if you get rails from abandoned mineshafts this design can even save you resources!).

One-Button Cannon with a Dispenser used as delay
This cannon is semi-automatic, once you press the button, it not only lights up the "boosters" but also shoots out an item out of a dispenser that will slowly fall down through a pressure plate on a fence and burn. Saves up redstone, and is basically cheaper than the design above. Also cheaper than normal semi-automatic cannons with repeaters used as a delay.

TNT-Based Condensation (a.k.a., Condenser Charge)
TNT's seven block blast radius limits the size of TNT Cannon Charges because normal TNT cannon's charge with no condenser charge are limited to 7 blocks of TNT, with any more TNT wasted, as the shot is then out of the blast radius. Condensation charges work around this; they are separate TNT charges that do not effect the shot directly, but instead blasting the charge TNT closer to the shot which not only allows more impulse charges to be added, but increases the range of the TNT cannon to at least a third more of the range as it had previously. TNT condensation is still a very new innovation in TNTctech, and is still being heavily tested. It has definitely not reached its full potential yet. --ArkEneru

Piston-Based Condensation
Using pistons to push the Main Charge closer to the Shot also does the same thing as a Condenser Charge, more complicated to build but more controllable. To work, the Main Charge must be primed already, turning the solid TNT blocks into entities. Once they are entities, a series of pistons can push and concentrated all charges into a single block space behind the Shot. In this system, you get far more efficient power from a given size of Charge.

Example: Cannon with 18 Block Piston Charge Concentrator This cannon uses a two rows of pistons at the sides and a double pistons in the middle to concentrate 18 blocks of TNT into one spot. The TNT Charges are set off when they are pushed beside the column of redstone torches by other pistons. They then fall into the water and are push by the side pistons, putting them in a single row down the middle of the water trough. Then, a double piston extends and pushes all the blocks forward into one spot behind the Shot.

Care must be taken so that the pistons do not displace the water blocks protecting the cannon from TNT damage. To do this, one usually has to apply water a block above the area where the pistons would go into. It is also advised that the pistons should RETRACT back into normal position before the Main Charge explodes, or your cannon might be destroyed. When the pistons extend, they create air spaces in the water no matter what, hence compromising the water's protection.

Waterless Cannon
Most TNT cannons require water to fire them without destroying the cannon. An alternative is to build them out of an explosion-resistant material, particularly obsidian. Waterless TNT cannons may fire farther because there is no water to absorb the explosion shock. See Tutorials/Dry cannon for construction details.

Long range cannons
normally TNT cannons have a limit to very short or very large ranges here by meaning that if the player wants their cannon to shoot further than the cannons limit they cannot do so.However there is a loop hole the play should simply extend his or her cannon by 1 block and add another water source block to the end of their cannon and viola! The players cannon should now extend the limit by 5 or more blocks depending on the size of their cannon.

Shot Mounting Blocks
The shot mounting block for a cannon should be chosen according to how fast, far, and high you want the cannon to fire. Of course, these variables depend greatly on the position and amount of the charge and the timing of the shot, but the mounting block also can make a difference. For example, with a cannon with a charge of 5 and a delay of R4.3, the shot will take a mortar trajectory with a ladder more than with a fence post and pressure plate. A few things: --ArkEneru
 * Even though the shot mounting blocks ladder and full block are both the same height and fire a shot at the same trajectory, the ladder will consistently fire farther than the full block because the ladder has less matter in between the shot and the charge than the full block. This situation is the same for all mounting blocks, the half slab and fence post w/ pressure plate also follow the same rule.
 * There is a trade off: although the fence post and pressure plate fire the farthest, they are also expensive, while the half slab is cheap and easy to get, as while as coming in many forms.
 * The maximum range for any cannon can be achieved by altering the mounting block. A TNT shot will be fired farthest if it leaves the cannon at a 30 degree angle. So, if you want to just have your cannon go the farthest it can, use the half slab or other like mounting blocks. Howverer, when faced with fortifications or terrain obstacles, the best idea would be to have a mounting block that makes the TNT arc (BINGBINGBING WE HAVVVVE A WINNER) over the said obstacle. Then again, it is fun to blast your way through things...
 * The following shot mounting blocks are tested and deemed safe. Feel free to experiment with mounting blocks, but keep in mind that some blocks, such as a lone pressure plate, will cause a mis fire of your cannon, and of course make it self destruct. (woah Its fun to say that...)

No Mounting Block
Pros: Highest velocity, simple, scalable

Cons: poor range in smaller cannons, downward trajectory, line-of-sight only

When no mounting block is used, the Shot is either allow to fall onto the water trough or is place on the trough directly. the Shot will fire out completely horizontal, or 0°. Gravity will quickly pulled the Shot to the ground, giving a very flat, downwards trajectory.

With small TNT charges, the range can be extremely limited. To increase the range, ever larger charges are needed or the cannon must be built higher above the ground. A larger charge means a higher velocity to the Shot, pushing the Shot farther away before it drops to the ground.

Players have been known to use up to 70 TNT charges and beyond. But economically, a cannon without a mounting block will take more TNT and longer to load for a certain range.

Single Block


Pros: Higher firing angle, can lob shots

Cons: Low velocity, reduced power and extremely poor range for smaller cannons

A single full size block such as cobblestone or obsidian is placed under the Shot. This has the effect of elevating the Shot above the water trough, so the blast force from the Charge is applied not just forward, but upwards. The shot is fired out at a high angle and trajectory. This is useful for hitting a elevated target, or one behind terrain or obstruction.

However, part of the blast force is absorbed by a solid mounting block, so the cannon will suffer similar problems of needing large charge sizes. Also, since some of the energy is expelled in the upwards direction, forward shot velocity is reduced greatly.

A better alternative to the single mounting block is using a Ladder instead.

Half Block


Pros: Smooth trajectory (not too high, not too low), average velocity, more efficient for small and medium cannons 

Cons: Slightly reduced power, not best for either straight OR lob shots, fuse range limit * 

A half block is the compromise between a single block and no mounting, and generally more efficient than either. More of a cannon's blast force is directed forward, but there is still an upward vector that raises the angle of fire to roughly 30°. As with a single block, some of the blast energy is absorbed by the block, but much less. From the same TNT load, the half block has greater range than a single block or no block.

When the TNT Shot is initially placed over a half block, it will hang over the half block as if it was a full size block. Once the TNT has been "primed", it will fall down and sit on the true height of the half block.

The firing angle produced by a half block is good for extending the range of a cannon and hitting elevated targets, but its too low for effective lobbing over high walls and obstacles. For straight direct firing, shots fired with a half block mounting generally land level on the ground within a certain range. However, due to the limited fuse time of TNT in the game, scaling up the TNT charges up to a point will result in the shot flying too high and exploding in the air before it lands or reach the cannon's maximum range. This will be refer to as the "fuse range limit * ". All cannons are limited by the fuse range limit, but cannons firing at higher angles are especially prone to the fuse limit, as the shot velocity is lower and shots reach higher altitudes.

Trap Door


Pros: (closed) Optimized for flat trajectory, velocity almost the same as no-block, (opened) can be used in open position for higher firing angle, good scaling

Cons: Be sure that priming circuit doesn't activate the trapdoor by accident.

If the firing angle of the half block is too high for your purpose, a closed Trapdoor can be used instead. Like the half block, it provides some upward force to the shot by elevating it above the trough. A trapdoor, however, is only half the height of a half block. Firing angle is roughly 15-20°, making it extremely effective for straight shots at very long range (+180 block).

Little forward velocity is lost when firing, and shot typically fly out at very high speeds. This combine with the low firing angle means cannons firing larger loads can extend their range without encountering too much fuse range problems as with the half block or ladder mounting.

NOTE: Be sure that your priming circuit for the Shot doesn't activate the trapdoor, or open/closed the Trapdoor beforehand. (inapplicable as of 1.1)

Ladder/Iron Bars/Glass Pane


'''NOTE: As of 1.1, the removal of the collision box for Ladders means they will not support falling TNT anymore. But they can be replaced with Iron Bars or Glass Pane blocks for the same effect, but as of 1.2 the hitbox was added again.''' Pros: Efficient with small and medium cannons, High firing angle, parabolic trajectory, good for lobbing shots and high altitude

Cons: Low velocity, poor scaling, limited range at ±120 blocks

A Ladder placed on the side can serve as a very effective mounting block for firing at high angles and lobbing shots. A primed Shot will be supported by the edge thickness of the ladder, preventing it from falling into the trough. Because a Ladder is not a full size block, none of the energy from the blast is absorbed, and the shot is propelled out at full force. By adding ladders above each other, different firing angles can be achieved. Typically, a single ladder will give an angle just higher than a half block, roughly 40°-45°. Two ladders will give an extremely parabolic flight, shots fly out at about 50°-60°.

A good portion of the blast energy directed upwards on the block, so shot velocities are generally much slower than a no-mount or half block mount cannon. In return, a cannon have no problem lobbing shots over terrain and walls. At larger charge loads, shots can reach very high altitudes.

However, this also means the fuse range limit is a inherent problem with this mounting. Within a 100 block distance, well built cannons level with the ground can expect to land shots low enough to cause damage. But beyond this shots explode midair way beforehand, even with a shot primed at maximum fuse time with a delay circuit. Hence, one can't simply add more TNT to increase the range, as it will only make the shot fly higher. A basic solution is to put the cannon below ground, in a pit with a slanted slope to allow the shot to fly out. Since the shot had a lower starting point, it will explode closer to the ground once its fuse time runs out. To reach ranges beyond 150 blocks, this solution becomes impractical.

Fence and Pressure Plate
A new type of cannon invented by disco.

"Pros: Efficient with small and medium cannons, Low firing angle, good for shooting through caves and past overhanging base defenses. High velocity, extremely powerful in spread cannons and long range cannons.

"Cons: Expensive materials, can cause the cannon to self destruct if pressure plate is activated."

A fence placed at the end of the cannon tricks Minecraft to think that it is one block high, since it is only one and a half block high for the player's perspective. Therefore, the Charge would be recognized as closer to the Shot than it actually is. Since it gains more power and velocity, it appears to fly up a bit, then go down in an attack angle. This gives it a distinctive style of cannon shooting, and it is considered one of the most useful mounting blocks in Minecraft.

Spread cannons with fences at the end combine the power and velocity of the fence type mounting blocks. The only reason for the pressure plate at the end is for blocking the water.

Video examples

 * Mortar High Angle Shot using a ladder mounting block.
 * Compact The Shot is primed by hand, which must now be done with flint and steel.
 * Superlarge Cannon Firing other Entities.

Trivia

 * Cannons can launch any entity, including mobs, sand, gravel, or players. Sand and gravel can be used to mark the landing spot (assuming it doesn't despawn mid-flight). Tutorials/Mechanisms is a guide to building a human- (or other entity-) launching cannon.


 * Cannons are ineffective against water based defenses since TNT doesn't destroy any blocks when submerged.


 * Cannons are follow the South-West quirk and fire further when facing South or West.

Anleitungen/TNT-Kanone Tutoriels/Canons de TNT 教程/TNT大炮