How to find the right Threaded Inserts AI guide
Written by an AI model from its trained knowledge.
What the AI looks for in Threaded Inserts
- Base material
- Use heat-set or press-in inserts for thermoplastics, wood inserts for wood, and helical, key-locking or solid thread-in inserts for metals. Each insert type is designed to anchor in one kind of material, and the wrong one strips or cracks the part.
- Repair vs new design
- Use helical or thin-wall solid inserts to repair stripped threads, and key-locking or heat-set inserts to design in durable threads from the start. Repair inserts are sized to fit an oversized drill and tap of a damaged hole, while design-in inserts assume you control the hole from scratch.
- Internal thread match
- Match the insert's internal thread exactly to the bolt, including UNC/UNF or metric pitch. The insert's inside thread, not its outside, is what your bolt sees.
- Installation tooling
- Budget for the specific drill, tap or installer the insert requires (STI tap, heat-set tip, key-drive tool). Most failed installs come from using a standard tap or improvised driver instead of the matched tool.
- Insert material
- Choose stainless steel for corrosion and strength in metals and brass for heat-set and plastic applications. Check for galvanic issues in aluminum and magnesium. Material drives corrosion behaviour, strength and compatibility with the parent part.
Brands that matter
- HeliCoil: The reference helical insert system for thread repair and design-in threads in metal.
- Recoil: Widely used helical insert and kit maker, an alternative to HeliCoil.
- Time-Sert: Thin-wall solid bushing inserts popular for automotive thread repair.
- Keensert: Established key-locking insert line used in aerospace and heavy-duty work.
- E-Z Lok: Self-tapping and externally threaded inserts for metal, plastic and wood.
- Spirol: Industrial inserts for plastics, including heat-set and press-in types.
- PEM: PennEngineering inserts and fasteners for sheet metal and plastics.
- Ruthex: Brass heat-set inserts aimed at 3D-printed parts.
What to avoid
- Unbranded multi-size kits whose tap and inserts are not made as a matched set
- Using a standard tap instead of the STI tap a helical insert requires
- Heat-set inserts in thermoset plastics or resin prints that do not soften with heat
Questions
Helical coil or solid insert for a stripped hole?
Helical inserts are cheaper and thin-walled. Solid thin-wall or key-locking inserts resist being backed out and are preferred where the bolt is removed often or vibration is high.
Do I need a special tap?
For helical inserts, yes. They need an STI (screw thread insert) tap sized for the insert, not a standard oversize tap.