Best Jointers for Squaring Boards Before Planing
What's inside
As an Amazon Associate I earn from qualifying purchases. This post may contain affiliate links at no extra cost to you.
A jointer gives a board one flat face and one straight edge. A planer then makes the opposite face parallel to the first. That order matters: a planer can reduce thickness, but it will not reliably remove a board’s cup, twist, or bow on its own. For most small shops, a 6-inch benchtop or floor-standing jointer is enough to prepare typical furniture stock. The right choice depends more on board width, cutterhead, and available infeed and outfeed support than on motor horsepower.
As an Amazon Associate we earn from qualifying purchases at no extra cost to you.
Contents
What to look for in a jointer
Jointer capacity is set by the cutterhead width. A 6-inch machine can flatten boards up to about 6 inches wide in one pass; an 8-inch jointer can handle wider stock without ripping it narrower first. Wider machines cost more, weigh more, and need more floor space. If you mostly work with 4/4 lumber for boxes, shelves, and small furniture, a 6-inch jointer is usually the sensible starting point. Choose 8 inches if wide boards are a routine part of your work, not just an occasional inconvenience.
Bed length affects how easily the machine registers long boards. Short benchtop jointers take up less space and can work well on stock around 3 to 4 feet long, but longer boards need careful support. A long bed is more forgiving on 6-foot boards and helps maintain a straight edge. In either case, support roller stands can prevent a long board from tipping, but they must be set level with the tables rather than used to push the wood down.
For cutterheads, helical or spiral designs use small replaceable inserts and generally leave a smoother surface on figured or difficult grain. They are quieter in many setups and avoid the full-width knife changes required by straight-knife heads. Straight knives are cheaper to replace and perfectly capable of good work when sharp and properly aligned. A helical head is a convenience and finish upgrade, not a substitute for correct technique.
Joiner types compared
| Type | Best fit | Main trade-off |
|---|---|---|
| 6-inch benchtop | Small shops and occasional board prep | Short beds make long stock harder to control |
| 6-inch floor-standing | Regular use with common furniture stock | Uses more space; still limited to 6-inch boards |
| 8-inch floor-standing | Frequent work with wider boards | Higher purchase cost and larger footprint |
| Spiral-head jointer | Frequent use or troublesome grain | Higher initial cost; inserts still need maintenance |
Practical buying choices
For an occasional user who has limited room, a 6-inch benchtop jointer is a reasonable budget choice. Check that the tables are coplanar and that the fence locks square and stays put. Short tables are its real limitation: a machine may be rated for a long board, but keeping that board flat through the cut takes more attention and support. This option is fine for shorter parts and modest quantities; it is less pleasant for repeated preparation of long cabinet sides or table components.
If you prepare lumber regularly, a 6-inch floor-standing jointer is often the better value. Its longer tables and heavier stand make feeding stock easier and reduce movement during a cut. A straight-knife version can be a sound buy if you are willing to keep the knives sharp and set correctly. A wider spiral-head jointer makes sense when you often flatten boards wider than 6 inches or work with figured hardwood. It is a substantial investment, so do not buy the extra capacity just for a rare wide board that could be ripped and re-glued.
Joint the board before planing
Inspect each board first. Mark the cup, bow, and twist with pencil lines, and look for nails, grit, loose knots, or severe defects. Remove metal before cutting; a single nail can damage knives or inserts. If the board is wider than the jointer’s capacity, rip it into narrower pieces first. Do not try to joint an over-width board by tilting it or taking a partial cut: the result can be unstable and uneven.
Set a light cut, around 1/32 inch for ordinary flattening. Deeper cuts remove material faster but increase the chance of tear-out, chatter, and loss of control, especially on short or twisted stock. Place the cupped face down so the board rests on its two high edges rather than rocking on the middle. Feed with steady pressure over the infeed table at the start, then transfer pressure to the outfeed table once the flattened portion reaches it. Keep hands clear of the cutterhead and use push blocks; do not force the board down to hide a rocking defect.
Take repeated passes until the face is flat, checking with a straightedge or winding sticks. Stop as soon as the high spots are gone. Removing extra material wastes thickness and can leave too little stock for the finished part. For an edge, place the flattened face against the fence and take light passes until the edge is straight and square to that face. Check with a reliable square along the board; a fence set at 90 degrees is only useful if it is actually calibrated.
Then use the planer—and avoid common errors
Put the jointed face down on the planer bed. The planer references that flat face and cuts the opposite face parallel to it. If you feed a twisted board into the planer without first flattening one face, the rollers can press it flat temporarily; it springs back after the cut, retaining much of its twist. A planer sled can flatten one face when you do not own a jointer, but it adds setup time and reduces the amount of usable thickness.
Common problems include snipe at the ends, tear-out in reversing grain, and a board that comes out tapered. Snipe can be reduced by supporting the work and lifting the board’s leading and trailing ends slightly as they pass the cutter, following the machine manual. Tear-out calls for a shallower cut, a sharper cutter, and sometimes a different feed direction. Taper usually points to uneven pressure, poor support, or tables that are not aligned. Before blaming the machine, check that the board is stable on the infeed table and that you are not steering it sideways.
Budget for dust collection and safe support as well as the machine. Jointing creates chips quickly, and a clogged chute can interfere with operation. A jointer should have a guard that returns over the cutterhead, and the operator should use eye and hearing protection. With a sharp, aligned machine and sensible cuts, a basic 6-inch jointer can prepare plenty of stock for a small shop; pay for more width, bed length, or a helical head only when your work makes those features useful.
