Jointer vs thickness planer — what's the difference and which do you need?

For every woodworker the question comes sooner or later: jointer or thickness planer — which should I buy? The answer depends entirely on what kind of timber you work with. They solve different problems, and both are needed to go from rough timber to finished material. This guide explains the difference between the machines, the order in which you use them, and why a combined jointer-planer is the logical solution for most workshops.

The basic difference — 30-second answer

The jointer (Swedish: rikthyvel, German: Abrichthobel) makes a board straight and flat. It gives you a flat reference face and a square edge. The board becomes flat but not necessarily the same thickness throughout its length.

The thickness planer (Swedish: planhyvel, German: Dickenhobel) makes the opposite face parallel to the first flat face. The board becomes the same thickness throughout its length, but it requires that you already have a flat reference face to lay against the table.

In other words: the jointer creates flatness, the thickness planer creates thickness consistency [1][2].

Why the order matters

The classic beginner's mistake: trying to thickness a twisted board directly.

The problem: the thickness planer has feed rollers that press the timber against the table. A cupped or twisted board pressed flat under the rollers becomes flat while it's being fed — but springs back when it leaves the machine. Result: the board is still twisted, just thinner [3].

Correct workflow:

1. Jointer step 1: Flatten one face (the board's "best" side) until it is flat
2. Jointer step 2: Straighten one edge until it is square to the flat face
3. Thickness planer step 3: Place the flat face down on the table → the opposite face becomes parallel
4. Rip saw or a further jointer pass to make the 4th side square

After these four steps you have a squared board: flat, square, consistent thickness. From that foundation you can start building furniture.

Jointer construction

The jointer has two horizontal tables and a rotating cutterhead in the middle. The process:

• The infeed table sits slightly lower than the cutterhead (typically 1–2 mm)
• The outfeed table is level with the top of the cutterhead
• You push the board across the cutterhead with pressure over the outfeed table
• Each pass removes a thin layer from the underside

Result: the face becomes flat. You continue until the entire face has been machined (no unmachined "low" spots remaining). Once the face is flat you rotate the board 90° and run the edge against the fence for a square edge.

Limitations:

• The working width is the machine's maximum width (usually 150–410 mm for home workshops)
• The board must be longer than infeed table + outfeed table + chatter margin
• Cupped boards are taken down a little at a time — it is not possible to straighten a board with 5 mm of cup in one pass

Thickness planer construction

The thickness planer has one table beneath a cutterhead and feed rollers that pull the board through the machine.

• The table can be raised and lowered
• The cutterhead stays still — the surface above the table becomes thinner with each pass
• You set the desired thickness and let the machine feed the board automatically

Limitations:

• Requires a flat reference face to lay against the table
• Feed rollers press the timber — cupped timber will not come out flat
• Working width limited by the machine's capacity (typically 250–410 mm for home workshops)

The combination machine — jointer + thicknesser in one

Because you almost always need both machines, manufacturers combine them into a single design: a combined jointer-planer [4].

Construction:

• Jointer mode: two tables on top of the machine, open cutterhead
• Thickness planer mode: tables folded down, board fed through the machine under the cutterhead
• Switching via a lever mechanism — typically 30–60 seconds to change over

Advantages:

• Half the footprint compared to two separate machines
• Lower total cost — around 60–70 % of two separate machines
• Same cutterhead — no duplicate service costs

Disadvantages:

• Switching takes time — professional joinery shops with high throughput prefer two separate machines
• Same working width for jointer and thickness planer (not possible to have a wide thickness planer + narrow jointer)

For home workshops and smaller joinery shops, the combination machine is the right choice 9 times out of 10.

JET JPT series — the workhorse for the Swedish workshop

JET's JPT series is Sweden's best-selling combined jointer-planer. Three sizes:

• JPT-310 — 310 mm working width, 2.2 kW motor (230V or 400V)
• JPT-310HH — same but with helical cutterhead
• JPT-410 — 410 mm working width, larger motor, for larger workshops

JPT-310 (230V / 400V)

The best-selling size. Specs:

• Working width: 310 mm (enough for tabletops up to 30 cm wide — wider tops are edge-glued from boards)
• Cutting depth per pass: 3 mm jointer, 4 mm thickness planer
• Motor: 2.2 kW (230V single-phase or 400V three-phase)
• Feed rate: 6 m/min (thickness planer)
• Maximum timber: 160 mm thickness in thickness planer mode

Suits home workshops, smaller furniture joinery shops, and semi-professionals. The 230V model suits workshops without a three-phase supply.

JPT-310HH (helical cutterhead)

The same base machine as the JPT-310, but with a helical cutterhead. Small carbide inserts in a spiral pattern around the cutterhead instead of straight knives.

Advantages of the helical cutterhead:

• 3–4 dB quieter — a noticeable difference for neighbours and workshop ergonomics
• Cleaner cuts in difficult species — knotty boards and interlocked grain are handled without tear-out
• Longer service life per insert — each small insert can be rotated 4 times before replacement
• Lower cutting load — the motor runs more calmly

Disadvantages:

• 20–30 % higher purchase price
• In the event of damage: replace individual inserts (15–20 per cutterhead) instead of 2–3 straight knives

For serious furniture makers, the helical cutterhead is worth the premium — it pays for itself through fewer tear-out scrap pieces in more expensive species.

JPT-410

A larger sibling — 410 mm working width. Suits joinery shops that regularly work with wide tabletops or large furniture parts.

Decision tree — which do you need?

You buy pre-planed timber from a builders' merchant

Most building timber today is sold pre-planed (planed on all sides). In that case you don't really need a jointer — the only remaining requirement is to adjust to the exact thickness.

Recommendation: A thickness planer alone (JET JWP-12) is enough.

You buy rough-sawn timber from a local sawmill

Rough-sawn timber is typically around 25–30 mm thick but sawn — not planed. The faces are rough and the edges uneven. You need the full workflow: jointer → thickness planer → rip saw.

Recommendation: A combined jointer-planer (JET JPT-310 or JPT-310HH).

You work with reclaimed/older timber

Older timber is often twisted, cupped or has unmachined sections. You need full control from rough face to finished material.

Recommendation: A combined jointer-planer, preferably with a helical cutterhead (JPT-310HH), since older timber often has knots and cross-grain fibres.

You are a professional joinery shop with high throughput

Separate machines — a dedicated jointer + a dedicated thickness planer — give a faster workflow because no changeover between modes is needed.

Recommendation: Two machines; the JPT series works, but also look at Hammer or Felder for really large volumes.

Installation and operation

230V vs 400V (three-phase)

• 230V single-phase (JPT-310 230V version): suits standard workshops with only single-phase power
• 400V three-phase (JPT-310 400V version): lower current draw, more efficient, suits workshops that already have three-phase. When building a new workshop, three-phase is strongly recommended.

A dust collector is essential

Thicknessing generates large volumes of chips — a thickness planer without extraction fills a bin in 10 minutes. Requirement: at least a 1,500 m³/h dust collector (JET DC-1100 or equivalent) with a 100–150 mm hose connection.

Knife calibration

Straight knives in the JPT-310 need calibrating against the outfeed table when they are changed. Incorrectly fitted knives result in tapered cuts or tear-out problems. our magnetic knife setting jig makes this considerably easier.

A helical cutterhead (JPT-310HH) requires no such calibration — individual inserts are factory-set.

Safety

• Cutter guard is mandatory in jointer mode — finger injuries on the jointer are the most common workshop accidents on the woodworking side
• Use push blocks when you come closer than 15 cm to the cutterhead
• Timber shorter than 300 mm should not be jointed — use a hand plane or glue up first
• Dust extraction should always be running — inhaling fine planer chips is harmful

Recommendation — short answer

• Working with pre-planed timber → a thickness planer is enough (JET JWP-12)
• Working with rough-sawn or reclaimed timber → a combined jointer-planer (JPT-310 or JPT-310HH)
• Hardwoods and knotty timber regularly → helical cutterhead (JPT-310HH)
• Larger workshop, wide boards → JPT-410

Related

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• Bessey clamps — complete guide
• See all stationary machines

Sources

Last updated 2026-04-18.

1. The Wood Whisperer — Which Comes First: Planer or Jointer? An established industry source explaining the correct working order. thewoodwhisperer.com/articles/which-comes-first-planer-or-jointer
2. WoodWorkers Guild of America — Difference Between Jointer and Planer. Technical explanation of both machine types. wwgoa.com/post/the-difference-between-a-jointer-and-planer
3. Saws on Skates — Why Most Woodworkers Need a Planer First. Practical discussion of when a jointer vs a thickness planer is needed. sawsonskates.com/jointer-vs-planer
4. Wurth Baer Machinery — Thickness Planer vs. Jointer. Industry source on combination machines and use cases. wurthbaermachinery.com/thickness-planer-vs-jointer
5. JET JPT-310 product data (via resellers and the JET catalogue 2022 model) — 310 mm working width, 2.2 kW, 230V/400V variants.
6. CUTECH — Jointer vs Planer Knowledge. Construction details and decision models. cutechtools.us/blogs/knowledge/jointers-vs-planers