How to determine which planer you should use
Determine which planer you should use whether a surface planer, jointer or handheld power planer largely depends on what you need to accomplish, for though they’re all planers, they have different expertise.
Planers, whether they are stationary shop tools or portable jobsite tools have one thing in common: a spinning drum with knives to remove material and smooth the wood’s surface. The fast spinning drum with the carefully positioned and precisely ground knives strikes the board surface thousands of times a minute to remove small amounts of material and leave a clean, shaved and true surface after the cut.
The planer category includes the portable power planer, which is an improvement on the traditional hand planer. It provides a faster, less tiring way of removing material when fitting wood components together, such as planing a ceiling joist flat for drywall, shaving a sticking door, profiling a replacement board to fit into a damaged hardwood floor or removing roughness or old paint from a surface.
The wood jointer is used to create accurate dimensional boards, creating finished board from cheap lumber or even recycled material. The jointer is used to create an absolutely flat surface and a true vertical edge before the piece is put through the surface planer.
The surface planer then takes over making the other surface of the board absolutely flat so the top and bottom of the board are identical. Because the process was started with a jointer there won’t be any twisting or cupping.
Without the jointer’s first step, the surface planer cannot create or straighten a twisted or cupped board (although there is a way, which we’ll discuss later) but it does effectively reduce the lumber to a board of the required thickness.
Portable power planer
The portable or handheld power planer, which we’ll call a hand planer through the rest of this article, demands care and respect. But it’s very fast and simple to use. Just don’t try to remove too much material at one time. Better to take several passes of 1/16 inch.
To set the depth of cut, all hand planers use a fixed rear platen, a cutter drum with replaceable blades and an adjustable front platen. The depth adjustment is made using a rotary knob on top of the front platen that will probably have detent positions. That knob also doubles as a handle when using the planer.
There will be one, two or three blades on the cutter drum. Expect to make faster cuts with a hand planer with more blades and higher motor speeds. The blades shouldn’t require frequent changes but look at the blade or knife-clamping method to be sure it’s easy to use. Also, it may prove useful to look at a planer that has reversible blades that can be turned over when the blades get dull.
Another desirable feature is the ability to set the direction the wood chips will exit the tool, and there should be a switch that allows you to select a left or right direction. This can also be achieved by swapping the dust collector connector from one side to the other on some models.
Other features available are various guides for cutting rabbets or for helping position the planer on the edge of the board. A grooved front platen acts as a guide for making beveled edges. Also useful is a “kickstand” that flips down to prevent the blades from contacting the surface when the tool is idle.
To determine which planer you should use, keep in mind that the hand planer is much like using a conventional surface plane though it takes much less effort. It requires some concentration and, of course, care to keep the hand planer square to the board when planning an edge.
Cutting requires varying pressure on the hand planer. Apply most pressure on the front platen at the start of the pass. Then shift to pressing down on both platens through the middle section. And finally, shift pressure to the back platen as you complete the pass to avoid taking a deeper cut as the cutting head leaves the end of the wood.
A wood jointer is relatively simple to set up and use. Wood jointers are usually 6- or 8-inch tools, determined by the width of the cutting head. Generally, the 8-inch jointer is regarded as the more useful but it is more expensive. There are bigger machines as well, but they start to become prohibitively expensive unless the work you do justifies the investment.
The wood jointer has an infeed table and an outfeed table set at different heights. The difference determines the depth of cut.
The critical part of using the jointer is making sure the blades are set at the same height as the outfeed table or, for best operation one- to two-thousandths of an inch higher. This is best done using a straight edge. Place the straight edge on the outfeed table and rotate the drum. The knives should just brush the edge, and as a blade passes it will slide the straight edge slightly. When this movement is just 1/8 inch, the blade height is correct.
Align the fence so it’s at right angles to the feed tables. This can be done with an engineer’s square. Position the square next to the fence. If you see any light, it’s not square. Adjust the fence and recheck. Once the fence is set and the table height is correct, leave these adjustments alone unless you need to angle the fence to make an angle cut or replace blades.
As with the hand planer, the ideal cut with a wood jointer is 1/16 inch or less. To achieve this, set the infeed table using the gauge on the jointer.
Then, before you make a cut, inspect the lumber you’re jointing. If it’s cupped, put the concave side down and note the direction of the grain. Feed the piece into the jointer cutting with the grain as this will minimize any tear-out of the surface. Mark the surface you’ll be cutting with pencil or chalk, then continue making passes until all of the marks are gone. At that point your surface is true.
You’ll be creating the flat face on the piece on the outfeed side. Use a push block to hold the cut face down tight to the outfeed table surface. Use another push block or push-stick to feed the board. Only push with blocks over the cutter, never with your hands. If the board kicks out, your hand could drop onto the cutter.
Portable surface planers have a completely flat bottom table infeed and outfeed tables or rollers that are set at the same height. The spinning cutting drum is in the head of the planer. It removes material from the top.
Surface planers will size a board to the precise thickness required. What they will not do is true a board (see tip for a way around this). That’s because the planer has a roller feed that pinches the board top and bottom as it feeds it past the rotating blades. So if a board is cupped or twisted, the action of the feed will squeeze the board in the vicinity of the blades and duplicate the twist or cup as it passes through the knives. That’s why a jointer is used first to flatten one surface and one edge. Then as the board passes through the surface planer, it matches the surface the jointer has already cut on the other side.
The surface planer has an adjustable housing for the blade drum and feed rollers that can be cranked up and down to achieve the required thickness for the board. It has a polished bottom plate that the board slides over as it is pulled and pushed by the infeed and outfeed rollers.
Usually 1/32 to 1/16 inch of material is removed in a pass, though the hardness of the wood may allow more or less. The hand wheel to adjust the cutter head is usually geared so that a full revolution moves the planer head 1/8 inch. There will be a gauge showing the position of the cutting blades but it may or may not be correctly calibrated.
Some models also have a depth stop that can be set to the maximum thickness of material to be removed. The surface planer may also have a selector labeled ‘finishing cut’ and ‘dimensional cut.’ It’s really a speed control for the rollers. At low speed, you’ll get more blade cuts per inch and a finer finish. The speed control can only be adjusted with the planer running.
When using a planer, tremendous quantities of wood dust are created so a powerful shop vac or permanent dust-removal equipment should be attached to the planer head. Ear and eye protection are also required.
Under no circumstance should your hands ever be under the planer head. Beware of jams that can occur if a cut is too aggressive or as the knives start to dull. And, to avoid injury from kickbacks, stand to the side as you feed a board into the rollers.
For initial cuts, you can set the surface planer head height by testing the board. Insert the board and adjust the head height until the board clears, then lower the height adjust 1/16 inch or less and make the first pass.
It’s a good tip to draw pencil or chalk lines on the surface to be planed so you can see the progress of the wood removal. You’ll be able to see the high and low spots, and know when you have matched the surface of the other face of the board.
Another issue can result from the feed, where a couple thousandths of an inch of additional material is removed as the board moves into and out of the planer. This is called snipe. If possible, plane a board that is longer than you need and saw off the snipe on each end. Or you use a sacrificial board ahead of the workpiece at the beginning of the pass. Then as that board moves off the outfeed place it at the back of the workpiece where it can take the outgoing snipe, as well.
If the workpiece is fed in the wrong direction, tear-out can result. Flip the board around and plane with the grain.
Tip: If you have a board with twist, you can fix it with a surface planer even if you don’t have a jointer. To do this, make a plane sled using flat plywood a little wider than the workpiece. Hot glue wedges between the board and the sled until it’s doesn’t rock. Now run the workpiece through the planer. When the workpiece is completely flat, remove the sled, turn the board over and plane the other side. This technique can also be used on a cupped board, planing the concave surface first.
Tip: Lumber generally holds more moisture at the center than at the surface. As you remove the surface, you’ll expose moister wood. If possible, plane close to the required dimension and then allow the board to stabilize for a day or so. Then you can plane it to the final dimensions.
Planers have fast-spinning drums with exceedingly sharp blades. There is no room for complacency when using them, and jointers and hand planers especially must be treated with great caution. Always keep hands well clear of the spinning knives.
All three tools throw dust and fast-moving wood particles so eye protection is strongly recommended. Because of the dust, a face mask is also recommended. All should be used with ear protection, ideally for the operator and anyone nearby.
Never wear loose clothing or anything around your neck like a dangling pair of spectacles when operating the machines.
With the jointer, always use push blocks and push sticks. With the hand planer, always hold the tool with both hands so there is no opportunity to touch the blades.
Do not put down a hand planer or walk away from a jointer or surface planer until the drum has stopped spinning.