Quick answer: a two-flute spiral router bit is a solid carbide CNC bit with two helical cutting edges. The spiral geometry shears the material instead of chipping it, giving a cleaner edge and better chip evacuation than a straight bit, while the two flutes balance surface finish against feed speed. It is a general-purpose choice for wood, MDF, plywood and panel materials. To compare flute counts first, see single-flute vs two-flute router bits.
Designed for the job, specified for your machine
YINGBA two flute spiral router bits deliver balanced cutting geometry for dependable finish quality across wood, MDF, plywood and panel materials in general CNC routing.
Two cutting edges provide a practical balance of productivity, chip formation and finish. Right-hand, left-hand and application-specific spiral options can be reviewed for your hold-down method and required edge condition.
SR SERIES
Complete Size List — Two-Flute Spiral
Solid carbide two-flute spiral bits with stable chip evacuation for wood, MDF, plywood and panel materials. Balanced cutting geometry for dependable finish quality in general CNC routing.
| Code No. | Shank Ø (mm) | Cutting Ø (mm) | Flute (mm) | Overall (mm) |
|---|---|---|---|---|
| sr3-1-6 | 3.175 | 1 | 6 | 38 |
| sr3-1.5-6 | 3.175 | 1.5 | 6 | 38 |
| sr3-2-8 | 3.175 | 2 | 8 | 38 |
| sr3-2-12 | 3.175 | 2 | 12 | 38 |
| sr3-2-17 | 3.175 | 2 | 17 | 38 |
| sr3-2-22 | 3.175 | 2 | 22 | 38 |
| sr3-2.5-12 | 3.175 | 2.5 | 12 | 38 |
| sr3-2.5-17 | 3.175 | 2.5 | 17 | 38 |
| sr3-2.5-22 | 3.175 | 2.5 | 22 | 38 |
| sr3-12 | 3.175 | 3.175 | 12 | 38 |
| sr3-17 | 3.175 | 3.175 | 17 | 38 |
| sr3-22 | 3.175 | 3.175 | 22 | 38 |
| sr3-32 | 3.175 | 3.175 | 32 | 55 |
| sr4-12 | 4 | 4 | 12 | 40 |
| sr4-17 | 4 | 4 | 17 | 40 |
| sr4-22 | 4 | 4 | 22 | 45 |
| sr4-25 | 4 | 4 | 25 | 45 |
| sr4-32 | 4 | 4 | 32 | 60 |
| sr4-42 | 4 | 4 | 42 | 70 |
| sr5-22 | 5 | 5 | 22 | 45 |
| sr5-32 | 5 | 5 | 32 | 55 |
| sr6-17 | 6 | 6 | 17 | 45 |
| sr6-22 | 6 | 6 | 22 | 45 |
| sr6-25 | 6 | 6 | 25 | 50 |
| sr6-32 | 6 | 6 | 32 | 55 |
| sr6-42 | 6 | 6 | 42 | 70 |
| sr6-52 | 6 | 6 | 52 | 80 |
| sr6-65 | 6 | 6 | 65 | 100 |
| sr8-25 | 8 | 8 | 25 | 60 |
| sr8-32 | 8 | 8 | 32 | 60 |
| sr8-42 | 8 | 8 | 42 | 70 |
| sr8-52 | 8 | 8 | 52 | 80 |
| sr8-62 | 8 | 8 | 62 | 100 |
| sr10-32 | 10 | 10 | 32 | 70 |
| sr10-42 | 10 | 10 | 42 | 75 |
| sr10-52 | 10 | 10 | 52 | 80 |
| sr10-62 | 10 | 10 | 62 | 100 |
| sr10-82 | 10 | 10 | 82 | 120 |
| sr10-100 | 10 | 10 | 100 | 150 |
| sr12-42 | 12 | 12 | 42 | 75 |
| sr12-52 | 12 | 12 | 52 | 80 |
| sr12-62 | 12 | 12 | 62 | 100 |
All dimensions in millimetres. Sizes not listed can be produced on request.
Recommended materials
- Hardwood and solid wood
- Thick acrylic sheet and multilayer board
- Aluminum profiles and brass
- Carbon-fiber board
Typical specification range
| Shank diameter | 3.175–12 mm |
| Cutting diameter | Approx. 1–12 mm |
| Cutting length | Approx. 6–100 mm |
| Overall length | Approx. 38–150 mm |
Exact availability and suitability depend on the selected geometry, workpiece material, machine and cutting conditions. Please confirm the final specification before ordering.
Machines and applications
- CNC wood-cutting machines
- CNC engraving machines and routers
- Small CNC machining centers
- Profiling, slotting, edge trimming and sheet processing
Share your machine model, spindle speed range, workpiece material and target finish. Our team will help match the tool geometry to the application.
OEM & ODM options
- Custom shank, cutting diameter, cutting length and overall length
- Flute geometry and cutting direction for the intended process
- Coating options where applicable
- Laser marking and export packaging
- Sampling and production quantities reviewed against your specification
What to send for a quote
- Tool drawing or required dimensions
- Material to cut and desired finish
- Machine type, spindle speed and feed conditions
- Required quantity, marking and packaging
Drawings can be sent after your website inquiry by email to sales@yingbatools.com or by WhatsApp.
Catalog size matrix
Two-flute right-hand spiral end mills for balanced cutting performance and chip evacuation. Dimensions are in millimetres.
| Shank Ø | Cutting Ø | Cutting length | Overall length |
|---|---|---|---|
| 3.175 | 1–3.175 | 6–32 | 38–55 |
| 4 | 4 | 12–42 | 45–65 |
| 5 | 5 | 22–32 | 45–55 |
| 6 | 6 | 17–62 | 45–100 |
| 8 | 8 | 25–100 | 60–150 |
| 10 | 10 | 32–100 | 65–150 |
| 12 | 12 | 32–100 | 70–150 |
Catalog ranges show available size families; exact diameter/length combinations, stock, MOQ and lead time are confirmed in the quotation.
Recommended materials
Hardwood, solid wood, aluminium profiles, thick acrylic, multi-layer boards, carbon-fibre board and brass; application must be confirmed.
Typical machines
CNC wood cutting machines, CNC engraving machines, CNC routers and small CNC machining centres.
Two-flute spiral vs single-flute vs compression bit
| Bit | Best for | Limitation |
|---|---|---|
| Single-flute | Acrylic, PVC and plastics; maximum chip clearance | Coarser finish in wood; lower feed per pass |
| Two-flute spiral | General CNC routing in wood, MDF, plywood and panels; balanced finish and productivity | Fine dust in MDF needs good extraction |
| Compression | Clean top and bottom edges on two-sided laminated panels in one full-depth pass | Only works on full-depth through cuts |
The right choice depends on the material and the edge you need. For a full flute-count comparison see single-flute vs two-flute router bits, and for the compression-specific case see compression router bits: when and how to use them.
Frequently asked questions
What is a two-flute spiral router bit used for?
General CNC routing of wood, MDF, plywood and panel materials, including profiling, slotting, edge trimming and sheet processing. The spiral shears the material for a cleaner edge than a straight bit, and two flutes balance finish quality against productivity.
Should I use a two-flute or a single-flute bit?
For finish quality and productivity in wood and panels, two flutes are usually the better balance. For acrylic and plastics, where chip clearing and heat are the main issues, a single-flute bit is generally preferred. See the full comparison.
What is the difference between up-cut, down-cut and compression bits?
An up-cut spiral pulls chips upward, which gives good evacuation but can fray the top face on a through cut. A down-cut pushes chips downward, which gives a clean top face but poor evacuation in blind cuts. A compression bit combines both spiral directions to clean the top and bottom edges in one full-depth pass.
When should I use a compression bit instead?
Use a compression bit when you need clean edges on both faces of a two-sided panel, such as melamine, veneered plywood or laminate, in a single full-depth through cut. For shallow or blind cuts a single-direction bit is usually the better choice.
What shank size do I need?
Match the shank to your machine collet. 3.175 mm (1/8 inch), 6 mm, 6.35 mm (1/4 inch), 8 mm and 12 mm are common. Smaller shanks suit light finishing passes, while larger shanks handle heavier cuts and longer reach.
Related guides and tools
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