In Minecraft, acquiring resources efficiently is key to long-term survival and large-scale builds. One such resource is string, which is typically obtained by killing spiders, breaking cobwebs, or bartering with piglins. However, in technical Minecraft circles, players often turn to automation to gather items in large quantities. This is where a string duper comes into play. A string duper is a machine or contraption that allows players to duplicate string using game mechanics and glitches typically relying on behaviors involving cobwebs, dispensers, and piston systems. While duplicating may not be officially supported, it is often used on servers and in solo worlds where efficiency is the goal. Here’s how you can create a string duper in Minecraft, along with the materials, method, and tips to get it working reliably.
What Is a String Duper?
Understanding String Duplication
A string duper is a contraption that exploits certain game mechanics to produce infinite string without needing to farm spiders or gather cobwebs manually. Typically, these contraptions use minecarts, dispensers, and Redstone to repeatedly break cobwebs while collecting the string output. These setups are especially useful on technical survival servers or in creative testing environments where resource generation is automated.
Version Compatibility
String dupers often rely on bugs or unintended mechanics, which means their functionality may change between game updates. They are more common in Java Edition, especially versions prior to major bug fixes. Always test the design in your current Minecraft version before building it in a survival world.
Materials Required
Basic Components for a Simple String Duper
To build a basic string duper, you’ll need the following items:
- 1 or more cobwebs
- 1 dispenser
- 1 piston (preferably sticky piston)
- 1 observer
- Redstone dust
- Redstone repeater
- Minecart with hopper (optional for collection)
- Rails (optional)
- Solid blocks (e.g., stone, dirt)
- Shears (placed in the dispenser)
Some designs may require additional items depending on complexity or server rules. The key concept is to automate the breaking of cobwebs to convert them into string repeatedly.
How to Build a String Duper
Step-by-Step Setup
Below is a guide to build a basic string duper. Please note that this relies on the ability to regenerate or reset the cobweb block via piston movement or glitch-based duplication methods, depending on version:
- Place a cobweb on a solid block at eye level. This will be the target for duplication.
- Place a dispenser facing the cobweb. Load it with shears.
- Place an observer facing the dispenser or adjacent Redstone block to detect activation.
- Place a piston beneath or beside the cobweb to push it or an adjacent block.
- Use Redstone dust and a repeater to connect the observer to both the piston and the dispenser.
- Power the observer using a switch, clock circuit, or lever to activate the loop.
- Optional: Add a hopper minecart underneath or rails with a hopper system to automatically collect the dropped string.
The concept here is that the dispenser will shear the cobweb, converting it into string. Then, the piston will push a new cobweb or reset the block, triggering the process again. With the right timing and placement, the machine continuously breaks cobwebs, producing string in bulk.
Advanced Concepts and Tips
Using TNT Dupers (Risky and Complex)
Some advanced string duper setups use TNT dupers in combination with cobwebs placed by dispensers to mass-produce string by blowing up blocks. These designs are more complex and often dangerous in survival worlds, especially when not tested properly. They can also cause lag or be disabled on multiplayer servers.
Infinite Cobweb Source
To keep your duper running indefinitely, you’ll need a way to replace or reset the cobweb block. This can be done by:
- Using dispensers filled with cobwebs to place a new one automatically
- Designing piston mechanisms that reload the cobweb block
- Building a Redstone clock that regulates timing for repeated cycles
Efficiency Considerations
Always ensure your dispenser is loaded with enough shears or enchanted shears (with Unbreaking) to avoid frequent refills. Also, consider adding item sorters or overflow protection to prevent your storage from clogging with too much string.
Collection Systems
Automatic Pickup with Hopper Minecarts
One of the best ways to collect duplicated string is to place hopper minecarts underneath or near the location where the cobweb breaks. Rails should run underneath the output zone, and hoppers can then transfer the items to nearby chests for easy access.
Storage Expansion
As the duper generates large amounts of string, connect multiple chests using hoppers to build an efficient storage system. You can even sort the items if you have a more complex farm that also drops spider eyes or other materials.
When to Use a String Duper
Survival Megabases
Players working on large projects often need mass quantities of wool, bows, fishing rods, or scaffolding. String dupers provide a steady supply without needing to fight mobs repeatedly or travel through mineshafts collecting cobwebs.
Redstone and Auto-Farms
If you enjoy building farms or machines that require tripwires or dispensers, a reliable source of string becomes invaluable. String dupers let you build without resource bottlenecks.
Creative and Technical Worlds
Many players use dupers in creative mode or test worlds to experiment with Redstone and automation without worrying about running out of materials. They also allow for better understanding of game mechanics and timing setups.
Potential Issues and Warnings
Game Version Fixes
Because string dupers rely on unintended behaviors, Mojang may patch them in future updates. Always check whether your method still works in the latest patch or snapshot. This is especially important before updating a survival world.
Server Rules
On multiplayer servers, item duplication may be considered cheating or unfair play. Be sure to check the server’s rules before using or sharing dupers. Violating server rules can result in bans or rollbacks of your builds.
Lag and Performance
Redstone dupers, especially those that run on clock systems or involve TNT, can cause performance issues on lower-end machines or multiplayer servers. Use caution and test smaller versions before scaling up.
Creating a string duper in Minecraft is a powerful way to generate one of the game’s most essential resources automatically. While the method relies heavily on the current version and often exploits unintended mechanics, it can greatly improve your efficiency in technical builds and large-scale farms. Always remember to respect server rules, test your contraption carefully, and monitor updates that might affect your design. Whether you’re crafting wool for banners or building tripwire traps, a reliable source of string makes all the difference in progressing your Minecraft world. With thoughtful construction and creative Redstone engineering, you can build a string duper that fits seamlessly into your survival or technical setup.