Feed and Speed Calculator for MDF: Chip Load Chart & RPM
MDF cuts more predictably than any solid wood - it has no grain, no voids and no direction. What it has instead is a resin binder that is abrasive enough to consume cutters, and dust fine enough to be a genuine respiratory hazard.
For mdf, the recommended chip load runs from 0.152–0.229 mm per tooth on a 1/8″ cutter to 0.508–0.711 mm on a 1/2″. Typical spindle speeds sit between 16,000 and 18,000 RPM.
Your chip load is 0.3810 mm per tooth, which is within the recommended 0.305–0.457 mm range for mdf with a 6.35 mm upcut spiral.
MDF. MDF cuts freely but the resin binder is abrasive and will dull a cutter faster than any hardwood. Dust extraction is a health requirement here, not a convenience.
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.
How to cut mdf on a CNC router → - the full how-to: which bit, workholding, chip evacuation and reading the cut.
How mdf fails when the chip load is wrong
MDF rarely fails at the cut; it fails at the tool. Edge life in MDF is a fraction of edge life in hardwood at identical settings, and the first sign is usually a fuzzy edge appearing on a job that was cutting cleanly an hour earlier.
Setting up a cut in mdf
Because it is homogeneous, MDF tolerates the largest chip loads in the table, and it is the right material for testing a new toolpath before committing to expensive stock. Run extraction from the first cut, not once the pile gets noticeable.
The thing most people get wrong
The dust is the actual risk, and it is not a housekeeping issue. MDF dust is fine enough to stay airborne for hours and carries formaldehyde-based binder with it. Cut it with a dust shoe and extraction running, and do not dry-sweep the aftermath - that just puts it back in the air you are breathing.
Chip-load reference for mdf
Recommended chip load per tooth by cutter diameter, before any adjustment for depth of cut or bit geometry. Values between the 1/8″, 1/4″ and 1/2″ anchors are interpolated.
| Cutter diameter | Chip load (mm/tooth) | Chip load (in/tooth) |
|---|---|---|
| 1/16" (1.59 mm) | 0.152 – 0.229 | 0.0060 – 0.0090 |
| 1/8" (3.18 mm) | 0.152 – 0.229 | 0.0060 – 0.0090 |
| 4 mm | 0.192 – 0.288 | 0.0075 – 0.0113 |
| 6 mm | 0.288 – 0.432 | 0.0113 – 0.0170 |
| 1/4" (6.35 mm) | 0.305 – 0.457 | 0.0120 – 0.0180 |
| 8 mm | 0.358 – 0.523 | 0.0141 – 0.0206 |
| 3/8" (9.53 mm) | 0.407 – 0.584 | 0.0160 – 0.0230 |
| 1/2" (12.70 mm) | 0.508 – 0.711 | 0.0200 – 0.0280 |
These are estimates derived from published tooling-manufacturer data, not test results. Always prove a new setting on scrap first. Sources are listed on the methodology page.
Other materials
Already running a feed rate and want to know what chip load it produces? Use the chip load calculator.