Treetap is an IC2 hand tool that harvests 1 Sticky Resin per click from Rubber Tree resin spots.
Guide
Place 5 wood planks on the crafting grid in the IC2 treetap pattern: top-center, middle-left, middle-right, bottom-left. This yields one Treetap with about 28 uses of durability.
Locate a Rubber Tree in a swamp or jungle biome. Its Rubber Wood logs display dark resin spots that turn orange-yellow when an active resin pocket is ready to harvest.
Hold the Treetap and right-click directly on the yellow spot. The Treetap removes 1 Sticky Resin and the spot turns into an empty hole that refills over in-game time.
Place Sticky Resin into a Furnace; each piece smelts into 1 Rubber. Rubber is the base material for IC2 insulated cables, electric tools, and the Hazmat Suit.
Carry a backup Treetap because it breaks after about 28 uses. For a permanent solution, craft an Electric Treetap that consumes EU and never wears out from durability.
Planting a small Rubber Tree farm with bonemeal-grown saplings makes Sticky Resin renewable and removes the early-game bottleneck on IC2 cables.
Place 5 wood planks in the IC2 treetap pattern: one plank on the top-center, two planks on the middle-row left and right, and one plank on the bottom-left. This yields a single Treetap.
A Treetap extracts 1 Sticky Resin per right-click from an active resin spot on a Rubber Tree's Rubber Wood log. The spot then becomes empty and slowly refills over time.
Smelt Sticky Resin in any Furnace. Each Sticky Resin produces 1 Rubber, which is then used for IC2 insulated cables, electric tools, and the Hazmat Suit.
A regular wooden Treetap has about 28 uses before it breaks. Keeping a spare Treetap or upgrading to the Electric Treetap removes this limit.
The Treetap is a wooden hand tool with limited durability. The Electric Treetap is a powered IC2 version that consumes EU per use, is rechargeable, and never breaks from durability damage.