Miter saws have come a long way from their humble beginnings. I remember the heyday of the 9-inch blade, direct-drive Rockwell "Motorized Miter Box," with a particleboard sub-base and a thumb-pressed brake. It was my introduction to using a miter saw some 30 years ago.
I've come a long way, too, and now I install finish carpentry in houses that go for millions of dollars. Time is tight, and finish tolerances are even tighter, so I look for a saw that I can adjust quickly and accurately. Sure, some work requires the capacity of a slider, but a lot of trim jobs can be done with a good 12-inch compound miter saw. They are smaller and lighter to haul around the jobsite, and there are fewer moving parts to knock out of alignment during rough transport and hard use.
For a while this year, I put away my trusty old saws and tested eight new 12-inch compound miter saws to see how they performed on the job and in the shop. When the test was complete, I had a few new favorites.
Common items that all saws share are a 15-amp motor, automatic electric blade brake, and a dust bag. The saws all have a convenient top handle for lifting, but I would recommend carrying a saw with both hands under the base if it is off its stand. I worry about yanking the head too hard and throwing the saw alignment out of whack.
Adjustments. For adjusting miter angles, the top seven saws have detents to positively locate commonly used angles: 0, 15, 22.5, 31.6, and 45 degrees, and the miter ranges max out from 48 to 52 degrees.
When the old miter saws added the ability to bevel cut, they became real trimmers' tools. Cutting crown molding is one of the toughest cuts to make, but compound angle miter saws give you a choice of how to do it. You can still use the traditional method of standing your boards upside down, or you can lay your board face up and, with the correct bevel and miter angles, cut without wrestling to keep long stock snug against the fence.
The saws all have stops or detents at 0 and 90-degree bevel angles, and most of them also have a 33.9-degree detent setting for cutting crown. Those saws without this setting have at least a marking for it. The bevel ranges max out at 45 to 48 degrees.
Performance and Cutting Capacity. Without a doubt, the Ridgid out-cut the competition in terms of overall width capacity. It was the only saw that could cross-cut a 2x10. I'm no engineer, but I believe the blade center being farther away from the fence is the reason. The Ridgid will cross-cut up to 9-3/8 inches at 90 degrees without tilting up the front of the workpiece. I measured the others as follows: Hitachi 8-/16, DeWalt 8-1/8, Makita 8-1/16, Bosch 8, Milwaukee 8, Ryobi 7-15/16, and Craftsman 7-3/4 inches.
When I tested cross-cut capacity on a 4x6 timber, set wide end down, every saw except the Ridgid cut all the way through. The geometry that makes it a wide, flat cutter works against it with a taller block.
No saw could cut through a 4x4 at a 45-degree bevel angle, nor could any cross-cut a 6x6. The capacities in the specs (page 36) are based on the widest and thickest pieces that could be cut laying flat. Much taller pieces can be cut vertically against the fence, but that height depends on the board width.
For my time trials, I aggressively cross-cut 4x4 white oak post material using the stock blades that came with each saw. The fastest by far was the Makita, so if its performance is a 10 out of 10, the rest follow as such: Craftsman 9; Bosch, Hitachi, and Milwaukee 8.75; DeWalt and Ridgid 8.5; and Ryobi 8. As evident by the close scores, there is not a dog in the bunch. Any of these saws has enough guts to cut quickly and–if you treat them well–accurately, too.