Ryobi 18-Volt 10-inch Dual-Bevel Sliding Miter Saw
By Ralph Mroz
The Ryobi 18-Volt 10-inch Dual-Bevel Sliding Miter Saw (Model P3650) has been on the market a couple years now and proven itself. With its full feature set and attractive price, it’s a good option for many people, DIY’ers and pros alike. Many people think of Ryobi as strictly a DIY brand, but the logic that pigeon holes a brand into a “DIY” or “pro” category is flawed. We’ve written a whole article on that subject. Here we’ll take a look at this saw and tell you what it does and how well it does it.
A Miter Saw is a Little Unusual
Before we go into our analysis it’s important to understand what we expect a miter saw to do at all. In this regard a miter saw is not like too many other power tools. That’s because depending on the job, the same saw is sometimes expected to do tasks ranging from rough framing to delicate finish work. No one expects to use their framing nailer on trim, nor their brad nailer for timber framing. A recip saw (sawsall) is pretty much always a tool for crude jobs, while a small scroll saw is dedicated to precise wood working. But people expect their miter saw — especially in 10- and 12-inch versions — to handle tasks across the board (with different blades, of course). In this context, the constraints on the range of tasks a miter saw can handle are basically its power and precision.
The precision of a miter saw will determine whether it’s suitable for finish or cabinet work. For most paint-grade molding or trim, excruciating precision isn’t necessary — the joints are going to be caulked and painted anyway. But when you get into stain-grade work, particularly if you’re doing cabinetry or furniture building, precision counts. Now, how much precision do you need? That depends largely on how much sanding you’re willing to do. After all, cutting a piece is only the first step in fitting it.
If you’re willing to cut, fit, sand a little, fit again, sand a little more, and so on until the joint is perfect, then you can live with a less precise miter saw than someone who expects to cut and hopefully not sand at all. And how much sanding you’re willing to do probably is related to how often you do this kind of high-end work. If you do it a lot you want to eliminate as much time-consuming sanding as possible. If you do it only now and then, you may not mind the sanding as much and can live with a less precise (and less expensive) saw.
Fractional Inches or Thousandths?
A miter saw — especially a double-bevel sliding one — is a complicated beast, and its precision is a factor of many things. The most important items though are probably table flatness, the fence flatness and its square to the table, blade angle alignment, blade run out, and blade deflection. All of these things can be adjusted — some easily and by design, and others with so much difficulty that you’re better off returning the saw.
Most general carpenters — those that do a wide variety of jobs within the trade, what we call a Type 3— probably use a combination square to assess their jobsite miter saw. If it looks flat and square with this tool, it’s good to go for most field jobs. This method will allow you to tune your saw to a fine fraction of an inch — say 1/32nd or even 1/64th. On the other hand, the saws used in a carpenter’s cabinet shop may be more precise.
Now this can be taken to extremes. After all, a miter saw is a saw that cuts wood, not a machine tool that cuts steel, where tolerances of 1/1000 (a thousandth) can be had. Bottom line: a miter saw calibrated with a (known square) combination square will usually be sufficiently precise for most people most of the time.
The Good and the Great
The Ryobi 18-Volt 10-inch Dual-Bevel Sliding Miter Saw uses 2 ONE+ 18-Volt batteries for 36-Volt running power. This is great because you can use your existing Ryobi ONE+ 18-volt batteries and charger. (All Ryobi chargers will work, some faster than others.) Ryobi claims that the saw will make over 800 cuts per charge of the batteries. I’m not sure how this was measured (length of cut, cuts before resting the batteries, rest period, ambient temperature, etc.).
However, numerous reviewers have stated that they were able to run the saw almost continuously for hours at a time with only a partial depletion of the batteries. In the end, the exact details aren’t relevant here. The important point is that if you need to use the saw in a remote location for much of the day doing normal work, you should be fine on a single charge.
The maximum 90-degree cross cut width is 12-inches, with a max height of 3.5 inches. The saw miters 45-degrees left and 50-degrees right. At a 45-degree cross cut the max width is 8 inches.
The fences are 3.5-inches high (the left fence is fixed, the right fence is sliding and removable). Both fences are lower near the blade to accommodate maximum bevel-angle cuts.
The 10-inch blade is mounted on a 5/8-inch arbor spinning at 4000 rpm (no-load). There are miter stops at 0°, 15°, 22.5°, 31.6°, and 45°, and a detent over-ride. There’s an adjustable cut-line laser.
The soft-start brings the motor up to speed in about one second. I’ve heard it argued that mounted saws don’t need a soft start. However, since a miter saw will be cutting somewhat delicate moldings that you’re holding in place, it just might be a handy feature. The brake stops the blade in about two seconds.
The saw comes with a three-year limited warranty.
The Could be Better
The work clamp doesn’t work well as included. It needed heat shrink tubing or a tab of duct tape on the axle in order to function (both of which are easy to do). Another thing that takes some getting used to is that the power switch safety lever is a little funky to operate (on the flip side, you won’t accidentally activate it). If you want to adjust the bevel angle stops, you’ll need a 3mm Allen wrench which isn’t included. Also, I had one of the recessed Allen head bolts that adjust the fence cam out on me and I had to use vice grips to operate the bolt. None of these are big deals.
Out of the Box Accuracy
The first thing I did after assembly was to check the accuracy of the saw, following the directions in the manual. This is always recommended with a new saw and while it does take an hour or so, it makes sure that you get the best out of this complex machine. For this I used a 6- and a 12-inch combination square — both verified as square with a Starrett machinist’s protractor, and a two-foot level. Laying the level (the closest thing I had to a calibrated straight edge) across the entire table, I could see no daylight under any portion of it.
The table was thus confirmed flat, and all three segments of it (left fixed, rotating, and right fixed) were in the same plane. Laying the level across the fence, the one-piece fence was shown to be flat. Using the squares, I checked the squareness of the table to the fence, the fence to the blade, and the blade to the table. I had to make a small adjustment to the fence alignment with the blade, which was easy. I didn’t have a way to easily check blade run-out or deflection, but the kerf cuts (with the as-installed factory blade) were quite precise. And I did verify that I couldn’t deflect the blade with handle pressure at full slide extension any more than any other saw that I could get my hands on or that my local store had (which was negligible).
Frankly, considering that these saws are likely trued by hand at the factory, it’s amazing to me that they come so nearly perfect out of the box.
What I couldn’t correct easily was any inherent slop in things like bushings, bearings, arbor straightness, arbor to case squareness, and so on. For that I’d need to cut something. Perhaps the most common method for assessing a saw’s precision is with the four-cutor thetwo-cut method. I used the four-cut method and to my astonishment found that my nearly out-of-the-box saw cut at 90-degrees to five thousands across 9.5 inches (which extrapolates to 6 thousandths at 11.5 inches) — which is less than 1/128 of an inch across 11.5 inches. That is astounding accuracy given that the more-or-less standard for a precision saw is usually thought of as 1/64-inch over 11.5-inches. And this was with the unadjusted factory blade!
For vertical precision I performed the two-cut method on an upright 2×4 and arrived at less than 1/64-inch of difference from top to bottom of the cut.
Power and Sawdust
OK, this is a battery-powered saw. It naturally wasn’t as powerful as some of the corded miter saws that I’ve used. But I had no complaints cutting 2x KD stock.
The Ryobi 18-Volt 10-inch Dual-Bevel Sliding Miter Saw went as fast as I wanted to move it. There’s no standard here, so let me just give you one data point that you can use for comparison. I could push through a 4×4 PT that was reasonably dry (a couple months out of the lumber yard in a covered shop) in four seconds.
While the included sawdust bag collects most of the sawdust, a fair amount still manages to get thrown about. With a vacuum attached to the dust port though, the amount of stray sawdust was quite shop-friendly.
Great Customer Service
I had to call Ryobi customer service twice. Once to determine that the bevel stop adjustments had to be made with a 3mm Allen wrench (the manual didn’t say what size wrench to use on the highly recessed socket set screws). And the second time to ask what the threads of those set screws were because I backed one out too far, lost it, and had to replace it (answer: 6x12mm). In each case I didn’t have to wait long and got transferred quickly to a person who could answer my question. In a world of crappy customer service, this is a very bright spot for Ryobi.
All in all I was very impressed with this saw.