Wood Planer Guide: Thickness Planers, Jointers & How to Use Them

What Does a Wood Planer Do?

A wood planer — more precisely called a thickness planer — is a power tool that reduces a board to a uniform thickness by shaving material from the top face. The board passes on a flat table beneath a rotating cutterhead, which removes a thin layer of wood with each pass. By making multiple passes with progressively lower cutterhead settings, you bring the board to your desired finished thickness.

This capability is essential for serious woodworking. It lets you buy rough-sawn lumber (which is significantly cheaper than pre-surfaced stock), mill it to exact dimensions, and create boards of any custom thickness your project requires. Instead of being limited to the standard 3/4-inch thickness of S4S (surfaced four sides) lumber at the home center, you can produce 1/2-inch panels for drawer bottoms, 5/8-inch shelves, or 1-1/8-inch tabletops — whatever your project demands.

In this guide, we'll cover everything from how planers and jointers differ to selecting the right machine, using it properly, preventing common problems, and processing rough-sawn lumber from start to finish.

Planer vs. Jointer: Understanding the Critical Difference

The planer-versus-jointer confusion is one of the most common misunderstandings in woodworking, and getting it wrong leads to frustrating results. These two machines do related but fundamentally different jobs, and understanding the distinction is essential.

What a Jointer Does

What a Planer Does

A planer takes a board that already has one flat face and makes the opposite face parallel to it at a specified thickness. The board rides on a flat table, and the cutterhead above removes material from the top face. Because the planer references off the bottom face (pressing it flat against the table), it can only make the top face parallel to the bottom — it cannot remove twist, bow, or cup on its own.

Why You Need Both

The fundamental workflow for milling rough lumber requires both machines working in sequence:

1. Joint one face flat on the jointer (this becomes your reference face)
2. Joint one edge square to the flat face on the jointer
3. Plane to thickness by running the board through the planer with the jointed face down
4. Rip to width on the table saw

If you skip the jointer and run a warped board through the planer, the planer will dutifully make the top face parallel to the warped bottom face — giving you a board of uniform thickness that is still warped. This is the number one mistake new woodworkers make with planers.

Working Without a Jointer

If you can't afford or fit both machines, there are workarounds for jointing without a jointer:

• Planer sled: Build a sled from a flat piece of MDF or plywood and secure the warped board on top with shims, hot glue, or wedges to prevent rocking. The sled provides the flat reference surface the planer needs
• Hand planes: A hand jointer plane (#7 or #8) can flatten a face and straighten an edge, though it requires skill and practice
• Table saw jointing jig: A straight-edge jig on the table saw can joint one edge, and a planer sled handles face flattening
• Router sled: A large router on a flat sled can flatten wide slabs and panels that are too wide for a jointer

Types of Planers

Planers come in three main configurations, each suited to different workshop sizes, budgets, and usage levels.

Benchtop (Portable) Planers

Benchtop planers are compact, lightweight (typically 60 to 85 pounds), and designed to sit on a workbench or dedicated stand. They are the most popular type for home workshops and hobbyist woodworkers.

Typical specifications:

• Cutting width: 12" to 13"
• Maximum thickness capacity: 6"
• Motor: 15 amps (approximately 2 HP)
• Feed rate: 26 to 32 feet per minute
• Cutterhead: 2 or 3 straight knives, or helical with carbide inserts
• Price range: $350 to $700

Popular models include the DeWalt DW735 (widely considered the best benchtop planer), the Makita 2012NB, and the WEN 6552T. Despite their compact size, quality benchtop planers produce excellent results and can handle the vast majority of home workshop tasks.

Floor-Standing (Stationary) Planers

Floor-standing planers are larger, heavier (300 to 800+ pounds), and more powerful machines designed for serious workshops, professional shops, and high-volume work.

Typical specifications:

• Cutting width: 15" to 20" (some up to 24")
• Maximum thickness capacity: 8" to 12"
• Motor: 3 HP to 7.5 HP (220V or 3-phase)
• Feed rate: Variable, often 16 to 32 FPM
• Cutterhead: 3 or 4 straight knives, or helical with carbide inserts
• Price range: $1,200 to $5,000+

Floor-standing planers handle wider stock, remove material faster, produce smoother finishes (especially with helical heads), and run more quietly due to their mass and construction. They're essential for anyone regularly milling rough lumber in quantity or working with wide boards.

Combination Jointer-Planer

Combination machines serve as both jointer and planer in a single unit, sharing a cutterhead and motor. The table configuration converts between jointing mode and planing mode. European manufacturers like SCM, Hammer, and Felder have refined this concept into excellent machines.

Advantages: Saves floor space, costs less than buying separate machines of equivalent quality, and the cutterhead only needs one setup for both operations.

Disadvantages: Switching between modes takes time (typically 1 to 5 minutes), which is inconvenient when alternating between operations. You also can't joint and plane simultaneously, which slows batch processing.

Combination machines are an excellent choice for small shops where floor space is at a premium and production volume doesn't require simultaneous operations.

Key Specifications to Consider

When shopping for a planer, these specifications matter most for the quality of your results and the range of work you can handle.

Cutting Width

The maximum width of board the planer can accept. Benchtop planers typically handle 12" to 13" wide stock, while floor-standing models go up to 15", 20", or wider. Consider the widest boards you regularly work with and add a margin. If you plan to glue up panels wider than your planer's capacity, you'll glue first and then sand or hand-plane the joints flush rather than running the panel through the planer.

Depth of Cut

The maximum amount of material the planer can remove in a single pass, measured in fractions of an inch. Most benchtop planers have a maximum depth of cut of 1/8" (3mm), though optimal results come from lighter passes of 1/32" to 1/16". Floor-standing planers can handle deeper cuts due to their more powerful motors.

Feed Rate

The speed at which the power feed rollers move the board through the planer, measured in feet per minute (FPM). A standard feed rate is about 26 to 32 FPM. Some planers offer variable feed rates, which is a highly desirable feature — slower feed rates produce smoother finishes with less tear-out, while faster rates are efficient for rough dimensioning. The DeWalt DW735, for example, offers two speeds: 96 cuts per inch (fast) and 179 cuts per inch (fine).

Cutterhead Type

This is the single most important specification for surface quality and is covered in detail in the next section.

Number of Speeds

Single-speed planers run at one feed rate, which represents a compromise between speed and finish quality. Two-speed or variable-speed planers let you choose a fast speed for roughing and a slow speed for finish passes. Variable speed is a significant advantage for achieving the best possible surface finish.

Dust Collection

Planers produce enormous volumes of chips and shavings — more than almost any other woodworking machine. Effective dust collection is essential, not optional. Look for a planer with a 4-inch dust port (the standard for shop dust collection systems) and verify that it directs chips efficiently to the port. Many benchtop planers include a chip blower fan, but connecting to a proper dust collector or shop vacuum produces much better results.

Cutterhead Types: Straight Knife vs. Helical

The cutterhead is the heart of any planer, and the type of cutterhead has the biggest impact on surface quality, noise level, maintenance, and operating cost. Understanding the two main types helps you make an informed purchasing decision.

Straight Knife Cutterheads

Traditional straight knife cutterheads use two, three, or four long steel blades (knives) mounted in a cylindrical head. The knives span the full width of the cutterhead and slice the wood in a rotary shearing action.

Advantages:

• Lower initial cost (standard on most planers)
• Replacement knives are inexpensive ($15 to $40 per set)
• Can be resharpened multiple times by a professional sharpening service
• Quick knife changes on most machines (10 to 20 minutes)

Disadvantages:

• More tear-out on figured, interlocked, or reversing grain
• Louder operation (the full-width knife creates more air disturbance)
• A single nick in one knife creates a raised line on every board until the knife is replaced or resharpened
• Knife alignment must be precise — even a few thousandths of an inch off creates uneven cutting
• Dulls faster than carbide inserts, especially in hard or abrasive woods

Helical (Spiral) Cutterheads

Helical cutterheads use a cylindrical head studded with rows of small, square (or sometimes round) carbide inserts arranged in a spiral pattern. Instead of one long knife slicing across the full width of the board, dozens of small inserts take overlapping shearing cuts in a continuous spiral.

Advantages:

• Significantly less tear-out, even on difficult grain patterns (figured maple, interlocked tropical hardwoods)
• Much quieter operation — often 50% less noise than straight knives
• Longer edge life (carbide lasts 5 to 10 times longer than HSS steel knives)
• When an insert dulls or chips, simply rotate it 90 degrees to expose a fresh edge — each insert has four usable edges
• No precise alignment needed — inserts are indexed by their screw hole and seat automatically
• Less stress on the motor due to the shearing cut pattern

Disadvantages:

• Higher initial cost ($200 to $500 extra on benchtop, $400 to $1,000 extra on floor models)
• Individual insert replacement cost adds up if all inserts need changing at once
• Leaves a very faint scalloped texture (usually invisible after sanding with 150-grit or finer)

Our recommendation: For most woodworkers, a helical cutterhead is worth the investment. The reduction in tear-out alone saves significant time and material, and the ease of maintenance (rotate an insert in 30 seconds versus spending 20 minutes changing and aligning knives) pays dividends over the life of the machine.

How to Use a Thickness Planer: Step-by-Step

Using a planer is straightforward once you understand the proper technique. Here's a detailed step-by-step guide to getting the best results.

Step 1: Prepare Your Board

Ensure at least one face of your board is flat (ideally jointed). If working with rough-sawn lumber, joint one face first. Check for nails, staples, embedded grit, or other foreign objects that could damage the cutterhead — run a metal detector over reclaimed wood. Brush off any dirt, sawdust, or debris from the board surface.

Step 2: Determine Grain Direction

Identifying and feeding with the grain direction is critical for preventing tear-out. Look at the edge of the board — the grain lines should angle downward in the direction of feed, like smoothing an animal's fur from head to tail. If the grain angles upward into the cutterhead, the knives will catch and lift the fibers, causing tear-out. When in doubt, mark the feed direction with an arrow on the board.

Step 3: Set the Depth of Cut

Step 4: Set Up Infeed and Outfeed Support

For boards longer than a few feet, set up roller stands or auxiliary tables at the infeed and outfeed sides of the planer. These support the weight of the board as it enters and exits the machine, which is critical for preventing snipe (the deeper cut at the ends of the board caused by the board tipping as it engages and disengages the feed rollers).

Step 5: Feed the Board

Place the board flat on the planer bed with the jointed face down (this is your reference surface). Feed the board into the planer straight and centered. The power feed rollers will grab the board and pull it through — don't push or resist, just guide the board to keep it feeding straight. Never reach into the planer while it's running.

Step 6: Check Results and Repeat

Inspect the planed surface for tear-out, snipe, and uniform thickness. Measure thickness at several points with calipers. Adjust the depth setting and make additional passes until you reach your target thickness. Alternate which face you plane if both faces need to be surfaced, removing approximately equal amounts from each side to balance internal stresses and minimize warping.

Step 7: Final Finishing Pass

For the smoothest possible surface, take a very light final pass of 1/64" to 1/32" with a slow feed rate (if your planer has variable speed). This produces a surface that needs minimal sanding before finishing.

Snipe Prevention Techniques

Snipe is the single most frustrating issue with thickness planers. It manifests as a slightly deeper cut in the first and last 2 to 3 inches of a board, creating a visible depression. Understanding what causes snipe and how to minimize it will dramatically improve your results.

What Causes Snipe

Snipe occurs because the board is only supported by one feed roller (instead of two) as it enters and exits the planer. With only one roller pressing down, the board tips slightly upward into the cutterhead, resulting in a deeper cut. The severity varies by machine design, board length, and technique.

How to Minimize Snipe

• Use infeed and outfeed support: Roller stands or auxiliary tables that match the planer bed height prevent the board from tipping at the ends. This is the single most effective snipe-reduction measure
• Feed boards end-to-end: When planing multiple boards, feed them with their ends touching so there's never a gap where the trailing edge of one board and the leading edge of the next are unsupported. Sacrificial boards at the beginning and end of the batch absorb the snipe
• Take lighter passes: Lighter cuts (1/32" or less) produce less snipe because there's less cutting force to deflect the board
• Apply slight upward pressure: As the board enters the planer, apply gentle upward pressure on the leading end. As it exits, apply gentle upward pressure on the trailing end. This counteracts the tipping tendency. Be careful not to push the board up into the cutterhead
• Lock the cutterhead: Some planers have a head lock or table lock mechanism — engage it after setting your depth to add rigidity to the height adjustment mechanism
• Leave extra length: The most reliable method: leave your boards 3 to 4 inches longer than final dimensions and trim the sniped ends off after planing

Grain Direction and Tear-Out

Tear-out — where the planer lifts and tears wood fibers instead of cleanly slicing them — is the other major quality challenge in planing. Understanding grain direction is the key to preventing it.

Reading the Grain

Wood grain rarely runs perfectly parallel to the board's surface. It typically angles at a slight pitch. When the cutterhead rotates into rising grain (grain angling upward toward the cutterhead), it catches under the fibers and tears them out. When it rotates into descending grain, it slices cleanly.

To determine the correct feed direction:

• Look at the board's edge: The grain lines visible on the edge show the angle. Feed the board so the grain angles downward in the direction of travel
• Feel the surface: Run your hand along the board in both directions. The smooth direction is the correct feed direction; the rough or "catchy" direction is against the grain
• Mark it: Once you determine the correct direction, draw an arrow on the board so you remember

Dealing With Difficult Grain

• Upgrade to a helical cutterhead: The shearing cut action of helical heads dramatically reduces tear-out on figured wood
• Take very light passes: 1/64" per pass reduces the cutting force and minimizes tear-out
• Increase the feed rate: Counter-intuitively, a faster feed rate takes smaller bites per revolution, reducing tear-out (though it also produces a slightly rougher surface texture)
• Dampen the surface: Lightly misting the board surface with water softens the fibers slightly and can reduce tear-out. Allow the board to dry before finishing
• Accept some tear-out and sand: For mildly figured wood, light tear-out can be sanded smooth during finish preparation

Maintaining Your Planer

Regular maintenance keeps your planer cutting cleanly, extends blade life, and prevents premature wear on the machine.

Blade/Insert Inspection and Replacement

Inspect your blades or inserts regularly for dullness, nicks, and chips. Signs that blades need attention include:

• Increased tear-out on previously smooth-cutting boards
• Fuzzy or burnished surface instead of a clean cut
• Raised lines or ridges on the planed surface (indicates a nick in the blade)
• Increased noise or vibration during cutting
• The motor working harder (bogging down) on normal cuts

Table and Roller Maintenance

Keep the planer table clean and waxed. Apply paste wax (not silicone spray, which can interfere with finishes) to the table surface every few sessions. This reduces friction, helps boards feed smoothly, and prevents rust. Clean the feed rollers periodically with mineral spirits to remove pitch and resin buildup that can cause boards to feed unevenly or slip.

Dust Collection

Empty your dust collector bag or bin before it's more than half full — a full bag reduces airflow and allows chips to accumulate inside the planer, which affects cut quality and can cause jams. Periodically remove the planer's top cover and clean out chips that accumulate around the cutterhead and in the chip-ejection path.

Planing Rough-Sawn Lumber: The Complete Workflow

One of the biggest advantages of owning a planer (and ideally a jointer) is the ability to buy rough-sawn lumber and mill it yourself. Rough lumber costs 30% to 50% less than surfaced lumber and is available in a much wider variety of species, widths, and thicknesses from lumber yards, sawmills, and online suppliers.

Step 1: Acclimate the Lumber

Allow rough lumber to acclimate to your shop's temperature and humidity for at least a week (ideally two weeks) before milling. Sticker the boards (place thin sticks between layers for airflow) and stack them flat and level. Lumber that isn't acclimated will warp after milling as it adjusts to the shop environment.

Step 2: Plan Your Cuts

Before milling, plan how you'll cut your parts from the rough boards. Account for material loss during surfacing — typically 1/8" to 1/4" total from a rough board (1/16" to 1/8" per face). A rough 4/4 board (1 inch rough) will typically yield a finished board between 3/4" and 13/16" thick after surfacing both faces.

Step 3: Crosscut to Rough Length

Cut boards to rough length (3 to 4 inches longer than final dimension) before milling. Shorter boards are easier to flatten and less prone to snipe. Crosscutting also lets you cut around major defects like knots, cracks, and wane.

Step 4: Joint One Face

Run the concave face of the board across the jointer, taking light passes until the entire face is uniformly flat. Mark this face with a triangle (the traditional cabinetmaker's mark) so you always know which is the reference face.

Step 5: Plane to Thickness

Place the jointed face down on the planer bed and plane the opposite face. Take light passes until you reach your target thickness. If you need to remove a lot of material, alternate between faces (taking off equal amounts from each) to balance internal stresses and minimize warping.

Step 6: Joint One Edge

Run one edge across the jointer with the reference face against the fence. This creates an edge that is straight and square to the face.

Step 7: Rip to Width

Set your table saw fence to final width and rip the board with the jointed edge against the fence. This gives you a board that is flat, parallel, square, and dimensioned to your exact specifications.

Thickness Reference Chart

Here's a reference chart showing rough lumber designations, their actual rough thicknesses, and typical finished thicknesses after surfacing both faces:

Common Planer Problems and Solutions

Board Won't Feed

If the feed rollers aren't gripping the board, the rollers may be dirty (clean with mineral spirits), the board may be too thin for the planer's minimum thickness (typically 1/4" to 3/8"), or you may be trying to take too heavy a cut. Clean the rollers, reduce the depth of cut, or use a carrier board to support thin stock.

Ridged or Rippled Surface

A washboard or rippled surface indicates the feed rate is too fast relative to the cutterhead speed, the knives are dull, or the board is vibrating during the cut. Slow the feed rate (if variable), sharpen or replace the blades, and ensure the board sits flat on the table without rocking.

One Side Thicker Than the Other

If the planed board is thicker on one side than the other, the planer table may not be parallel to the cutterhead, or the board is being fed at an angle. Check table parallelism using the manufacturer's adjustment procedure, and feed boards straight and centered on the table.

Burning or Glazing

Burn marks or a glazed, shiny surface indicate the board is moving too slowly through the cutterhead (dwelling), the knives are dull, or the depth of cut is too light. Increase the feed rate, sharpen the blades, or take a slightly deeper cut. A board that stalls in the planer will burn almost immediately.

Safety Considerations

Planers are generally safer than many other woodworking machines because your hands don't get close to the cutterhead, but they still demand respect and proper safety practices.

• Never plane stock thinner than the manufacturer's minimum (typically 1/4" to 3/8"). Thin boards can shatter or be kicked back
• Never plane stock shorter than the manufacturer's minimum (typically 12" to 14"). Short boards can be caught and kicked back violently
• Never reach into the planer while it's running — for any reason
• Always wear hearing protection — planers are among the loudest shop tools
• Always wear safety glasses — chips and debris can be ejected from the planer at high speed
• Use dust collection — the fine dust produced by planers is a respiratory hazard and a fire risk
• Check for metal before planing — especially in reclaimed wood. Nails, staples, and embedded objects destroy blades and can become projectiles
• Never plane across the grain — the board will not feed properly and can be damaged or ejected
• Stand to the side — not directly in line with the board, in case of kickback

Final Thoughts

A thickness planer is one of the most transformative tools you can add to your workshop. It unlocks the ability to buy rough-sawn lumber at significant savings, mill boards to any custom thickness, and achieve the precise, uniform dimensions that professional-quality woodworking demands.

For most home woodworkers, a quality benchtop planer like the DeWalt DW735 provides excellent results at a reasonable price point. If your budget allows, a helical cutterhead upgrade pays for itself in reduced tear-out, less noise, and lower maintenance. And if you're serious about milling rough lumber, pairing your planer with a jointer — or at minimum, learning the sled workaround — is essential for consistently flat, true results.

For more tool guides and woodworking techniques, explore our articles on table saws, wood joint types, workbench plans, and wood finishing.