Answering the typical buyer question: which 1-3/8 inch drill bit best fits wood projects, hinges, and pocket holes? This guide compares top 1-3/8 inch bits, highlighting who each is best for, why it stands out, and potential limitations. It helps woodworkers, DIY enthusiasts, and professional shop operators choose confidently. The table below summarizes five strong options to help you compare at a glance.
| Product | Type | Best For |
|---|---|---|
| IRWIN SPEEDBOR Tri Flute Wood Drill Bit 1-3/8″ | Tri-flute wood bit | Fast chip ejection for general-purpose holes in soft to medium woods |
| StormCube Forstner Bits 35mm (1-3/8″) | Carbide-tipped Forstner | Precise, smooth holes with minimal tear-out in hardwoods |
| RURITKIT 1-3/8″ Forstner Bit | Forstner with hex shank | Accurate mortises and shallow pockets with secure chuck fit |
| WOBLLMX 1″ x 9″ Auger Bit | Auger with Tri Flute | Deeper holes in soft to hard woods with clean chips |
| REKCKRUL 1-3/8″ Forstner Bit (Hex Shank) | Tungsten carbide forstner | Hardwood, plywood, and dense materials with long service life |
IRWIN SPEEDBOR Tri Flute Wood Drill Bit 1-3/8″
Reference: Product Type is drill bits; package dimensions are listed; made in China. The tri-flute design aims to speed chip removal, which helps continuous drilling in wood. Best for general purpose drilling in soft to medium woods where a fast feed is desired.
Best for: DIYers and small shops needing quick, straightforward wood holes. Limit: data highlights generic features; consider coating wear if drilling dense hardwoods often.
StormCube Forstner Bits 35mm (1-3/8″)
Features include a carbide-tipped edge with high hardness and wear resistance. The bit is designed to cut cleanly with minimal burrs, even in end-grain and through knots. The shank is steel 45#, and drilling depth is 54mm with total length 88mm.
Best for: Projects requiring precise, clean pocket holes or hinge mortises in hardwoods. Limitation: carbide tips may require careful drilling to avoid glazing on very hard woods.
1-3/8 Inch Forstner Bit for Wood (RURITKIT)
Made from ASTM 5140 steel with a hardened body and a universal hex shank. Center-positioned teeth plus a serrated edge promote smooth cutting through hard and soft woods with reduced slipping. Hex shank ensures a secure fit in most chucks.
Best for: Mortising and pocket-hole work where consistent bore geometry matters. Limitation: drilling through very dense woods may slow the feed rate; keep steady pressure.
WOBLLMX 1″ x 9″ Auger Drill Bit
Auger design with a Tri Flute and a 3/8″ hex shank. Diameter is 1″ with a total length of 9″. It’s suited for soft to hard woods and features hollow centers to speed chip clearance and keep the bit straight for a clean bore.
Best for: Deeper holes in softwoods and medium-density woods. Limitation: performance can vary with very dense species or drilling in plywood without pilot holes.
REKCKRUL 1-3/8″ Forstner Bit With Hex Shank
Premium tungsten carbide-tipped cutters with a hardened steel body; hex shank reduces bit rotation and slipping. Designed for hinge mortises, cabinet knobs, and deep pocket holes. Depth is 60mm (2-3/8 inch).
Best for: Professional woodworking tasks requiring high durability and precision in hardwoods. Limitation: carbide tips are sharp and require careful handling to avoid chipping when misaligned.
Buying Guide: Key Purchase Considerations
What should you evaluate when buying a 1-3/8 inch drill bit set or single bit?
- Material and construction: Forstner vs auger vs tri-flute. Carbide-tipped blades offer longer life in hard woods; high-speed steel is common and versatile for metal and wood.
- Shank compatibility: Hex shanks prevent slipping in chucks; ensure your drill accepts hex or round shanks.
- Drill depth and bore geometry: For hinge mortises and pocket holes, a bit with the correct cutting depth matters to avoid over-penetration.
- Chip ejection and cutting efficiency: Tri-flute designs speed chip removal; Forstner bits provide clean, flat-bottomed holes.
- Workpiece material: Hardwood vs softwood; consider carbide-tipped bits for harder species to reduce dulling.
Frequently Asked Questions
- What is the difference between a Forstner bit and an auger bit? Forstner bits create flat-bottomed, clean-sided holes ideal for hinge mortises and shallow pockets. Auger bits bore deeper holes with a screw tip that pulls the bit through wood, which is efficient in long holes.
- When should I choose a carbide-tipped bit? Use carbide-tipped bits for dense hardwoods or repetitive heavy-duty drilling to extend bit life and maintain sharpness.
- Do 1-3/8 inch bits fit all drills? Most drills with a 3/8″ or larger chuck can accommodate 1-3/8″ bits, especially with hex shank variants. Always verify chuck size and shank compatibility.
- Is hex shank better than round shank? Hex shanks reduce slipping in chucks under high torque; round shanks are more common but may rotate if not tightly clamped.
- How do I avoid burrs when using Forstner bits? Ensure workpiece is supported, use a slow feed rate, and consider backer boards to reduce tear-out on exit.
- Can I use these bits on metal? These bits are designed for wood; use metal-specific drill bits when drilling metal to avoid rapid wear or breakage.