The Delta and DeWalt DW734 have manual locks that hold the cutterhead tight and keep it from twisting or racking when planing. The Delta has a side handle that tightens, while the DeWalt DW734 has a bar that snaps into place for locking down the head, which I like a little better because it is faster–snapping down and back up quickly. The locking-head feature has been omitted in the four newer units, because their four-threaded post, head-raising mechanisms provide more friction than the previous two-threaded post designs. The Makita is of the older design but features a self-locking friction ring, as does the four-post DeWalt DW735.
Thickness and Depth of Cut Gauges
The Craftsman planer has a unique digital readout to gauge final board thickness as well as the depth of a cut. I was somewhat skeptical of the usefulness of this feature, but to its credit, the digital readout proved accurate and easy to use–a real help throughout our tests. Other planers have a simple, resettable dial on the crank handle that you watch to see how deep the next pass will be, and a simple scale and pointer on the face of the tool to approximate the resulting board thickness.
A handy feature on all the planers is the depth-stop system to establish consistent and standard cuts. Most are set for common thicknesses somewhere between 1/8 and 1-3/4 inches. The system is essentially a series of mechanical stops that keep the traveling head assembly from moving past a set point. Makita has a single settable stop that works from the lowest point to 4 inches high, and Delta's similar stop can be set up to its entire 6-1/2-inch height.
All of the tools except the Delta have a simple precut indicator that shows how much stock the next pass will take off. Most feature a little pointer and scale, but Makita's is a steel pin that lifts up to indicate the cut depth. None of these provide accurately calibrated measurements, but any type of indicator that lets you see how much you are about to cut is important. Delta has a zero-depth finding indicator that locks down even with the height of the knives. When the head is lowered flush to the board, the indicator disengages and springs up. This lets you accurately zero-out the depth scale on the crank handle and adjust downward from there. I like the scaled indicators best; they give the most information and are the easiest to use.
The use of a thickness planer assumes some type of return pass to the infeed side of the machine. In a two-man operation, the "catcher" passes boards back to the "feeder" over the top of the machine.
The Craftsman and Delta have rollers that make the return pass easier. Delta's roller is coated with foam rubber and rolls easily, but won't balance a board for one-man operation. The Craftsman has bars that sit loosely in grooves and will spin. The DeWalt DW735 has raised aluminum wear plates on its top, and the Steel City tool features sturdy steel bars. The rest of the machines rely on using their flat roofs. Ridgid's crank handle is mounted on the side to make it easier to pass boards over the top without interference, and the others' handles fold mostly out of the way, except for the Craftsman and DeWalt DW734.
All of the tools except the Makita come with a dust collection adapter fitting, and some will attach to a shop vacuum. The DeWalt DW735, Ridgid, and Steel City machines have a chip diverter attachment that must be used if the machine is not connected to a dust collector.
The default mode of the planers is to spray the chips out the back, which creates a huge mess and can lead to clogged chip diverters. This happened to the DeWalt DW734 and Makita planers when we ran thick cuts on wide boards. The DeWalt DW735 and Craftsman have an extra chip-extraction blower motor that provides a lot more airflow while breaking up shavings into smaller chips. The Craftsman tool also has a dust filter bag that attaches to the top of a 30-gallon garbage can. The force of the blowers on the DeWalt DW735 and Craftsman means you don't need to attach them to a separate vacuum system if you can vent them near the work area. This is a great in a small shop or jobsite without a dedicated dust collector.