What's inside
- What a Jointer Planer Actually Does
- Before You Set Up the Machine
- Useful Setup Numbers
- How to Set Up Jointer Mode
- How to Joint a Flat Face
- How to Joint a Square Edge
- How to Thickness-Plane the Board
- Grain Direction, Tear-Out, and Snipe
- Can You Use a Jointer as a Planer?
- Ownership Realities and Common Mistakes
- A Reliable Workflow for Finished Boards
- Related Guides
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To use a jointer planer, first create one flat reference face and one square edge on the jointer, then turn the board over and thickness-plane it to a parallel, uniform dimension.
What a Jointer Planer Actually Does
A combination jointer planer, also called a planer-thicknesser, performs two different jobs with the same cutter block. In jointer mode, the board passes over an infeed and outfeed table to create a flat face or straight edge. In thicknesser mode, the board passes beneath the cutter block, supported by a bed, to make its opposite face parallel to the reference face.
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This distinction matters because a thickness planer alone normally follows the existing shape of the board. If both faces are bowed, it can produce a board with two smooth but still curved faces. The jointer establishes the first reliable reference surface; the planer then copies that reference at a controlled thickness.
Before You Set Up the Machine
- Read the machine manual and install the supplied guards, extraction hood, and push blocks correctly.
- Place the machine on a stable, level surface with enough room to support the board before and after the cutter block.
- Connect dust extraction before cutting. Fine wood dust can damage the machine and create a respiratory and fire hazard.
- Inspect knives or inserts for chips, looseness, and resin buildup. Replace or rotate them as specified by the manufacturer.
- Remove nails, screws, staples, loose bark, and embedded grit from the timber.
- Mark the board’s high spots, grain direction, and intended finished face with a pencil.
Keep hands away from the cutter opening, never reach over a rotating block, and disconnect power before changing knives, clearing a jam, or converting between modes. Use push blocks in jointer mode and stand to the side of the board rather than directly behind it.
Useful Setup Numbers
The correct setting depends on the machine, timber species, and board width, but these figures provide a practical starting point. Always stay within the manufacturer’s maximum cut and workpiece limits.
| Adjustment or task | Practical starting point | Why it matters |
|---|---|---|
| Jointer cut depth | 0.5–1 mm per pass | Reduces tear-out, motor load, and snipe-like dips at the ends |
| Thickness-planer cut depth | 0.5–1.5 mm per pass | Allows steady feeding without overloading the cutter block |
| Final smoothing pass | 0.25–0.5 mm | Improves surface quality and reduces chatter |
| Typical maximum board width | 250–330 mm for many compact machines | Wider timber may require a larger machine or hand-tool flattening |
| Typical stock allowance | 2–4 mm thicker and wider than finished size | Leaves material for flattening, tear-out, and final dimensioning |
| Support space | At least the board length before and after the machine | Prevents the board tipping as its weight moves across the tables |
How to Set Up Jointer Mode
1. Check table alignment
The outfeed table must be level with the highest point of the cutter arc. If it is too low, the board drops after passing the cutter and develops a hollow or snipe at the trailing end. If it is too high, the board cannot leave the cutter cleanly.
Place a straightedge across the outfeed table and rotate the cutter block by hand with the machine unplugged. A knife or insert should just touch the straightedge and move it slightly as the block turns. Do not adjust knife height by guesswork; use the manufacturer’s procedure.
2. Set the infeed table
Lower the infeed table by the intended cut depth. For a rough board, begin with approximately 0.5 mm. A badly twisted board may need repeated light passes rather than one aggressive cut. Confirm that the fence is square to the table and that the cutter guard covers the unused part of the block.
How to Joint a Flat Face
- Place the board’s concave face down if it can sit reasonably steadily. Remove obvious high corners or rocking points with light passes.
- Start the machine and allow the cutter block to reach full speed before feeding.
- Keep the board pressed down on the infeed table at the start. As enough board reaches the outfeed table, transfer pressure forward to the outfeed side.
- Feed at a steady rate without forcing the timber. A slow, uneven feed can leave burn marks; a fast feed can produce ridges or tear-out.
- Continue until the entire face has been cut. Pencil marks are useful: each pass should remove the marks from the high areas.
- Take another light pass only when necessary. Stop when the face is flat, not merely when a preset number of passes has been completed.
For a short board, use push blocks that maintain downward pressure without placing fingers near the cutter. For a long board, use infeed and outfeed supports set level with the machine tables. Never joint a workpiece shorter than the manual’s minimum length.
How to Joint a Square Edge
After one face is flat, place that face against the fence and joint one edge. Keep the reference face pressed against the fence and the edge firmly on the table. Make light passes until the edge is straight and perpendicular to the reference face.
Check the result with a try square and straightedge. If the edge is angled, verify the fence before taking more cuts. Jointing an incorrect angle repeatedly only makes the board narrower without solving the problem.
How to Thickness-Plane the Board
Convert the machine according to its instructions: remove or reposition the fence and guard, install the thicknessing table or extraction hood, and verify that the cutter block is fully enclosed. The flat jointed face goes down onto the thicknesser bed.
- Measure the board at several points and set the thicknessing bed slightly above the desired finished thickness.
- Feed the board with the reference face down. Let the feed rollers pull it through; do not push it forcefully once the rollers engage.
- Take a light first pass to identify high areas and check for tear-out.
- Lower the bed in small increments, commonly 0.5–1.5 mm, until the opposite face is clean and parallel.
- Rotate or mark the board consistently so you know which face remains the reference face.
- Finish with a shallow pass, then measure thickness at both ends and the middle.
Do not thickness-plane a board below the machine’s minimum thickness or above its maximum width. If a board is too narrow for reliable roller contact, use a carrier board only if the manual permits it and the assembly can pass safely under the cutter.
Grain Direction, Tear-Out, and Snipe
Feed with the grain whenever possible: the grain should rise toward the cutter in the direction the board travels, rather than lifting into the knives. Grain changes around knots and reversing figure can still tear out. Reduce the cut depth, slow the feed slightly, or use a final pass in the more favorable direction. Highly figured wood may require a very shallow cut and subsequent sanding.
Snipe is a shallow dip at the beginning or end of a board, usually caused by the board tilting as only one feed roller is gripping it. Reduce it by leveling support tables, keeping the board level as it enters and exits, and using light final passes. Some machines allow slight adjustment of the cutterhead or thicknessing table, but do not alter those settings without the manual’s procedure.
A useful technique is to feed a sacrificial board immediately before and after the workpiece. This keeps the feed rollers engaged and can move the snipe onto the scrap, provided the machine manufacturer approves the method and both pieces are suitable for the feed system.
Can You Use a Jointer as a Planer?
You cannot use a conventional jointer as a thickness planer in the normal sense. A jointer flattens one face or straightens one edge, but it does not reference the board from below to make the opposite face parallel at a controlled thickness. You can repeatedly joint the second face, but measuring and maintaining parallelism becomes difficult and the board may taper.
A combination jointer planer can perform both operations because it changes into thicknesser mode. That is how to use a jointer and planer in one machine: joint first, then thickness-plane. A separate jointer and planer provide the same workflow with more convenient changeover and often greater capacity.
Ownership Realities and Common Mistakes
- Knives and inserts wear first. Dull edges increase noise, tear-out, power consumption, and feed resistance. Keep a spare set or replacement inserts available.
- Resin affects accuracy. Clean tables and the cutter area with a suitable machine-safe cleaner; wax or protect tables only as directed, because some products can contaminate finishes.
- Dust extraction is part of setup. Blocked ports reduce airflow and can interfere with chip ejection, especially in thicknesser mode.
- Too much cut is a common error. Removing 2–3 mm from a wide hardwood board in one pass may overload a compact motor and worsen the surface.
- Short timber is risky. Respect the minimum length and width in the manual rather than relying on hand pressure to control a small workpiece.
- Accuracy depends on supports. A perfectly adjusted machine can still produce tapered boards when long stock is allowed to sag before or after the tables.
A Reliable Workflow for Finished Boards
For most projects, buy stock with several millimeters of extra thickness and width. Inspect it, mark the best face, joint that face flat, joint one edge square, thickness-plane the opposite face, and finally rip the board to width using the jointed edge against the table saw fence. Leave final planing until the wood has acclimatized to the workshop if its moisture content or storage conditions are uncertain.
This sequence answers the practical question of how to use a jointer planer machine: establish a reference, remove material gradually, control grain direction, support the workpiece, and measure after each stage. The result is more predictable than trying to flatten both faces at once or using the planer to correct a board that has no flat reference surface.