I am looking to buy a 12" miter saw, but there are so many different adjectives describing the tool: basic miter saw; compound miter saw; sliding compound miter saw; dual sliding compound miter saw, and I'm sure I've missed a few. I would be using the miter saw to cut trim molding, so which adjectives should I look for in my miter saw search?
Just to further Freeman's answer, one downside to the sliding compound mitre saw is the size - whenever you place it, you need a foot or so of clearance at the back so the blade can slide back and forth.
If you don't need the extra distance, I would recommend against it. (source: I purchased a sliding compound mitre saw about a year ago. I rarely need the full length of cut, and I still haven't found any where good in my small shop to keep it).
- Standard means that the blade will pivot around the horizontal axis, but remains 90° to the bed of the saw. This is the most basic variation, and is simply a powered version of grandpa's old miter box.
- Compound means that the blade tilts on the vertical axis as well as pivoting around the horizontal. Other than a few specialized models (mostly for cutting metal and/or cinder block, from my experience), most miter saws will be compound.
- Sliding means that the entire cutter head moves forward and back. This will give you the ability to cut wider boards while only using a smaller blade. This is usually added on to a compound miter saw, so it's the greatest combination of features. Note that if it has a smaller blade, the smaller blade will reduce the depth of cut you can make.
Either a compound or sliding compound would allow you to cut trim molding. You could probably do it on a 7¼" or 10" saw, but the 12" will give you more flexibility, especially if you ever need to cut large crown molding or find yourself using it for any other projects. (Due to the angles involved, a 12" blade may be required to cut all but the smallest crown molding.)
I used my 12" compound miter saw to cut vinyl siding, and having a sliding head would have been great for that because I didn't have enough depth - I had to make part of the cut, then turn it over and realign to finish the cut.
Other features to look for would be an integrated laser sight to ease line up of the cut, and accessories specifically made for your brand, such as stops or stands. The importance of those would depend on whether you're doing a little work around your house or planning on some professional quantity output.