Voron Screw and Hardware Guide — Bolt Sizes, Heatsets, and Fasteners

Reference Build Hardware

Understanding Voron hardware is critical for a successful build. Voron printers use a standardized set of metric fasteners across all models. Using the wrong screw length or type can crack printed parts, strip threads, or cause alignment issues. This guide covers every screw, heatset insert, washer, and T-nut you will encounter. Last updated: May 2025.

Screw Size Reference

M3 is by far the most common size in a Voron build. Almost all printed parts attach to the aluminum extrusion frame using M3 screws between 8mm and 16mm in length. M4 and M5 are reserved for structural frame connections where higher strength is needed.

Head Types

Button Head Cap Screw (BHCS)

Button head screws have a low-profile, domed head with a hex (Allen) drive. These are the standard for attaching printed parts to the frame. The low profile allows the screw head to sit flush or nearly flush with the printed part surface. Use M3 BHCS for the vast majority of printed part mounting points.

Socket Head Cap Screw (SHCS)

Socket head screws have a taller, cylindrical head. These are used where higher torque is required or where the screw head needs more clearance in a metal part. Common on extrusion corner brackets, motor mounts, and metal-to-metal connections. The taller head provides a deeper Allen socket, reducing the chance of stripping at higher torque.

Flat Head / Countersunk (FHCS)

Flat head screws sit flush with the surface when used in countersunk holes. These are primarily used for panel mounting — attaching acrylic or polycarbonate panels to the frame. The countersunk design creates a clean, flush exterior surface.

Heat-Set Inserts

Heat-set inserts (also called threaded inserts or brass inserts) are pressed into printed parts to provide strong, reusable metal threads. Voron parts use standard knurled brass inserts installed with a soldering iron.

Insert Installation Tips

Heat the insert using a soldering iron set to 250-280°C for ABS/ASA. Press straight in with firm, steady pressure. Do not rock the iron — this can enlarge the hole and reduce holding force. Allow the plastic to cool completely before threading a screw in. For best results, use a dedicated insertion tip on your soldering iron.

T-Nuts

T-nuts slide into the V-slot of aluminum extrusions and provide threads for mounting parts. Vorons use two main types:

• M3 Roll-in T-nuts — Spring-loaded ball bearing holds them in the slot. Used with M3 screws for mounting printed parts and accessories to the frame. Can be inserted anywhere along the slot.
• M5 Drop-in T-nuts — Standard hammer-head or spring-loaded T-nuts for M5 bolts. Used for structural frame joints, corner brackets, and Z motor mounts. Drop in from the end of the extrusion or use spring varieties that clip in place.

All Voron extrusions use standard V-slot (openbuilds-compatible) profiles. M3 roll-in nuts fit the smaller slot channel, while M5 drop-in nuts fit the larger outer channel.

Washers

Flat washers are used under screw heads and nut faces to distribute load and prevent galling. For Voron builds:

• M3 flat washers — Used on printed part mounting points where specified. Typically 7mm OD x 0.5mm thick.
• M4 flat washers — Bed mounting, extrusion brackets. 9mm OD x 0.8mm thick.
• M5 flat washers — Frame corner joints, motor mounts. 10mm OD x 1.0mm thick.

Spring washers (split lock washers) and external/internal tooth lock washers are sometimes used on high-vibration areas like motor mounts, though most builders prefer blue Loctite for thread locking instead.

Thread Locker

Thread locking compound prevents screws from vibrating loose. Two grades are commonly used in Voron builds:

• Loctite 242 (Blue) — Medium strength, removable with hand tools. Use on motor mount screws, frame bolts, and any metal-to-metal connection. This is the recommended thread locker for most Voron applications.
• Loctite 263 (Red) — High strength, permanent. Requires heat (250°C+) to remove. Use only where specified or on components that should never need disassembly.

Important: Never use thread locker on screws going into plastic threads or heat-set inserts. The compound can weaken the plastic or prevent proper insert seating. Only use on metal-to-metal joints.

Where to Buy Hardware

Most builders source hardware from China-direct vendors (AliExpress, Alibaba) offering complete stainless steel kits by model. These kits include every screw, washer, T-nut, and heatset insert needed for a specific Voron model. Popular vendors include LDO, Formbot, and FYSETC. For individual replacements, McMaster-Carr (US), Misumi (global), and Amazon are common sources.

Material note: Stainless steel (A2-70 or A4-80) is preferred for corrosion resistance. Zinc-plated carbon steel is acceptable but less durable. Avoid brass screws — they are too soft for structural connections.

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