Mechanics

Routing
Items passing through tubes will always try to go to the nearest valid destination.

The decision on which destination to go to is made upon hitting a junction. A junction is defined as a point where, not including the path the item came from, there are 2 or more possible directions for the item to go.

If an item has no valid destinations then it will attempt to find the nearest overflow destination. These include Extraction Tubes, Buffer Tubes, Requesting Tubes, and some others. Most tubes that can put items into the network can also act as an overflow destination. When items enter an overflow destination they will not be added to any attached inventories. They are stored inside an internal buffer and must be cleared before the tube they are being stored in can resume its normal function. These stuck items will automatically return into the network when a valid destination for them becomes available.

If the item has absolutely nowhere it can go (no valid destination and no overflow destination) it will randomly choose a direction when it hits a junction. Items will however, still obey filters, colors and any other restrictions as they would normally.

Item Coloring
Items can be colored by certain tubes. When colored, they can only pass through tubes that are either not colored, or colored with the same color.

Tube Painting
Some tubes can be colored to allow only certain colored items through them. To do this you need a piece of whatever colored dye you wish to use. Once you have that you simply right click with the dye on the tube. To remove the paint, you right click any water container (eg. Water Bucket, Water Bottle, etc.) on the tube.

Blocking Connections
Sometimes tubes will connect to tubes or blocks you don't want them to. Luckily, there are actions you can do to help.

Paint the tubes (for tube -> tube connections):

 * Tubes that are painted different colors will not connect to each other. This is a useful trick for dealing with lots of normal tubes in small spaces. However since not all tubes can be colored this method is not always applicable.

Use a Tube Cap

 * By sawing a tube in half using a saw from Forge Multipart, you will get 2 Tube Caps. These caps can be placed in between a tube and anything else to block its connection.

Use a Cover

 * Covers from Forge Multipart can be placed in between tubes and will block any tube from passing through it.