Threaded Inserts for Wood — Strong, Reusable Threads
Brass threaded inserts create durable, machine-threaded anchor points in wood. They’re ideal when a screw will be removed and reinstalled over time—think furniture, cabinetry, speaker enclosures, fixtures, and instrument work. Choose from flush-mount inserts for a clean, level surface or flanged inserts for extra bearing area in softer woods.
Why Choose Brass Thread Inserts in Wood?
- Reusable machine threads: Resist wear better than wood screws in high-cycle joints.
- Works in hardwoods & softwoods: Reliable holding strength when holes are sized correctly.
- Fast, tool-friendly install: Hex-drive styles seat quickly with an Allen key or driver.
- Corrosion resistant & non-magnetic: Brass performs well for indoor projects and electronics.
Picking the Right Insert
Flush vs. Flanged
- Flush-mount: Sits level with the surface—best where hardware must seat flat.
- Flanged: Built-in shoulder spreads load and helps resist pull-through in softer or end-grain applications.
Drive & Thread Styles
- Internal hex drive: Easiest to install straight and fast.
- External wood threads: Coarse knurls/threads bite into wood to resist rotation; consider a larger OD in dense hardwoods.
- Machine thread inside: Match to your hardware (e.g., #8-32, 1/4-20, M6).
Quick Install Tips
- Pre-drill the pilot hole: Use the maker’s chart for your part; as a rule of thumb, size close to the insert’s minor OD so external threads compress wood fibers without splitting. Test on scrap of the same species.
- Keep it square: Drive with a hex wrench/driver; clamp the work if possible.
- Depth control: Mark the driver so the insert stops just flush (or the flange fully seats).
- Optional adhesive: In MDF or end grain, a small amount of wood-safe epoxy can boost strip-out resistance—use sparingly and keep it out of the internal threads.
- Don’t overtighten: Snug is enough; over-driving can crush fibers and reduce holding power.
Common Uses
- Furniture: Knock-down frames, tables, and chairs for repeat assembly.
- Cabinetry & woodworking: Jigs, knobs, and fixtures that see frequent adjustments.
- Speakers & audio: Secure baffles and hardware to MDF or plywood without stripping.
- Repairs: Restore worn screw holes with a stronger, long-lasting machine bolt.
Thread Inserts for Wood — FAQ
What size pilot hole should I drill?
Use the insert’s pilot chart when available. If you’re testing, match the hole to the insert’s minor outside diameter so the wood threads bite firmly without splitting. Always test on scrap of the same wood.
Flush-mount or flanged—what’s better?
Use flush-mount where you need a perfectly flat surface for hardware. Choose flanged for softwoods, MDF, or end grain to increase bearing area and resist pull-through.
Will these work in hardwoods like maple or oak?
Yes. Size the pilot correctly, drive the insert square, and consider coarser external threads or a slightly larger OD for easier installation in dense species.
Can I use glue with a threaded insert?
Optional. A small amount of wood-safe epoxy can help in MDF, particleboard, or end grain. Keep adhesive out of the internal machine threads.
What length should I choose?
Choose an insert length that provides at least 6–8 engaged internal threads with your bolt and doesn’t break through the opposite face. Longer inserts increase pull-out resistance but need deeper pilot holes.
How do I prevent inserts from spinning out?
Use the correct pilot size, drive straight with a hex tool, and avoid over-torque. In softer wood, a flanged style or a tiny epoxy assist can help.
Are brass inserts strong enough?
In wood joints, the limiting factor is usually the wood fibers. Brass inserts provide excellent corrosion resistance and more than enough strength for furniture and woodworking. For metal, use inserts designed for metal.
Do I need metric or inch threads?
Match the insert’s internal thread to the hardware you’ll use—e.g., 1/4-20 for common furniture bolts or M6 for metric hardware.