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General Mechanics requires Minecraft 1.21.1, NeoForge 21.1.x, and Java 21. Make sure these are installed before proceeding.

Prerequisites

Before installing General Mechanics, ensure you have:
RequirementVersionNotes
Minecraft1.21.1Java Edition
NeoForge21.1.209+Not compatible with Fabric or Forge
Java21 (Oracle JDK)Must be Java 21
JEI (optional)19.25.0.322+Strongly recommended for recipe browsing

Installation

1

Install NeoForge 1.21.1

Download the NeoForge installer from neoforged.net and run it. Select Minecraft version 1.21.1 and follow the installer prompts.
java -jar neoforge-21.1.x-installer.jar
2

Download General Mechanics

Download the latest gm-1.21.1-<version>.jar from the releases page and save it somewhere accessible.
3

Place the JAR in your mods folder

Copy the JAR into your Minecraft mods/ folder:
%AppData%\.minecraft\mods\
4

Launch Minecraft

Open the Minecraft Launcher, select the NeoForge 1.21.1 profile, and click Play. The mod loads automatically.
5

Verify installation

On the main menu, click Mods and search for General Mechanics (mod ID: gm). You should see version 1.0.0.

Exploring the mod in-game

Once in a world, press E to open your inventory and look for the General Mechanics creative tabs:
  • General Mechanics — machines, tools, plastics, electrical components, upgrades
  • GM Elements — all element ingots, ores, dusts, plates, rods, nuggets
  • GM Fluids — all industrial fluid buckets
If you have JEI installed, press R on any item to see its recipes, or U to see what uses it. All General Mechanics recipes (Fabrication, Crushing, Fluid Mixing) are visible in JEI.

Your first steps

Finding elements

Elements generate as ore blocks throughout the world. Start by mining common elements like Copper, Tin, Aluminum, and Silicon. Smelt raw ore in a furnace to get ingots, then process ingots into dusts, plates, and rods using machines.

Crafting the Matter Fabricator

The Matter Fabricator is the core advanced crafting machine of General Mechanics. It processes Fabrication recipes — advanced multi-ingredient synthesis not possible in a standard crafting table. To use it:
  1. Craft a Matter Fabricator block (recipe visible in JEI)
  2. Place it in the world and connect it to a power source (FE/RF)
  3. Insert ingredients into the input slots
  4. The machine will process the recipe and deposit output in the result slot

Working with fluids

Many processes require industrial fluids. Collect fluids using buckets or fluid pipes. Key starter fluids include:
  • Crude Oil — foundation for petroleum processing
  • Sulfuric Acid — used in ore processing
  • Hydrogen and Oxygen — produced by electrolyzing water

Using machine upgrades

Right-click a machine to open its GUI. Upgrade slots accept upgrade cards that modify machine behavior. Start with a Speed Upgrade to process items faster, or an Efficiency Upgrade to reduce power consumption.

Next steps

Core Systems

Learn how elements, fluids, energy, and machines work together.

Machines Reference

Browse all available machines and their functions.

Upgrades

Discover all 16 machine upgrade cards.

Developer Guide

Build addon mods on top of General Mechanics.

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