A compression bit (carbide)
Upcut at the tip and downcut above, it leaves clean top and bottom veneers in a single pass. Carbide, because plywood's glue lines are abrasive and dull bits fast.
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How to cut plywood on a CNC router
The three things that matter most:
- Tearout on plywood is a bit-type problem, not a speed problem - a downcut bit gives a clean top edge, a compression bit gives clean top and bottom faces at once.
- The alternating plies mean a bit that cuts clean in one layer cuts across the grain in the next, so geometry matters more than in solid wood.
- Plywood's glue lines are abrasive and dull bits faster than solid wood - carbide, and expect more frequent changes.
Feeds & speeds calculator, pre-filled for plywood
Set your cutter diameter, flutes and RPM and read the feed rate and chip load. This is the same tool as the plywood feed & speed page, which carries the full chip-load reference table.
Recommended feed rate
450.0IPM11,430 mm/min
Plunge rate
148.5 IPM
3,772 mm/min
Chip load
0.3175 mm
0.0125″ / tooth
Chip load bandIn range
0.254 mm0.381 mm
Your chip load is 0.3175 mm per tooth, which is within the recommended 0.254–0.381 mm range for plywood with a 6.35 mm upcut spiral.
Table range for plywood at 6.35 mm0.254–0.381 mm
Depth factor (cut is 0.47× diameter)×1.000
Geometry factor (upcut spiral)×1.00
Feed = 18,000 × 2 × 0.3175 mm11,430 mm/min
Plywood. Alternating grain direction between plies means a compression bit earns its price here - it keeps both the top and bottom veneer intact.
Upcut spiral. The baseline the published charts assume. Chips are lifted clear of the cut, which keeps heat out of the workpiece at the cost of tear-out on the top surface.
Which bit to use
A compression bit is the standard answer for through-cutting plywood: it is upcut at the tip and downcut above, so it lifts the bottom veneer up-clean and presses the top veneer down-clean in a single pass. For cuts that don't go all the way through, a downcut gives the clean top edge. Use carbide - the glue lines eat cutting edges.
Feeds, speeds & depth of cut
Plywood's difficulty is structural, not thermal, so feeds are less fussy than the bit choice - but keep the chip load in a sensible window so the bit shears the veneers instead of fuzzing them. Get the exact starting figure from the calculator, pre-filled for plywood below, and lean on bit geometry for edge quality.
Workholding
Sheet goods want broad, even hold-down: a vacuum table is ideal, tabs and screws in the waste otherwise, and full support underneath so the panel cannot lift and tear. Through-cut parts should be tabbed so they don't shift free mid-cut and get thrown.
Reading your results
A clean plywood cut has crisp top and bottom edges and severs the glue lines without fringing. Fuzzy or splintered top edge means the wrong bit direction - move to downcut or compression. A rough bottom edge on a through-cut is the same story from the other face, which is exactly what the compression bit solves.
Common mistakes
- Blaming feeds for tearout - it is almost always the bit geometry. Use downcut or compression.
- Using HSS bits - plywood glue lines dull them fast; use carbide.
- Not supporting or tabbing through-cuts, so parts lift and tear or get thrown.
Tooling & parts for plywood
The consumables a fix like this usually calls for. Prices are live; we may earn a commission on a purchase, which never affects what we recommend.
In stock
Frequently asked
- What bit gives clean edges on both faces of plywood?
- A compression bit. It cuts upward at the very tip and downward above, so it pulls the bottom veneer up-clean while pressing the top veneer down-clean in one pass. It is the standard choice for through-cutting plywood and veneered panels where both faces show.
- Why do my bits go dull so fast in plywood?
- The glue lines. Plywood's adhesive layers are abrasive - far harder on a cutting edge than the wood itself - so bits dull faster than in solid timber. Use carbide rather than HSS and treat more frequent bit changes as normal for sheet goods.
Related
Feed & speed for plywood (the tool) →Tearout & fuzzy edges →How to cut hardwood →All material guides →
Tooling and technique are drawn from manufacturer documentation and established references; starting ranges are exactly that - the exact feed and chip load for your cutter come from the calculator above, never invented here.