HackSpace magazine

Graff SpeedCutter review: Spinny blades of awesome

By Ben Everard. Posted

The Graff SpeedCutter is a blade for angle grinders that converts them into wood-cutting and carving beasts. It’s a disc with three tungsten carbide teeth available for 115 mm (4½ inch) or 125 mm (5 inch) grinders.

It must be said, it’s a terrifying tool. Angle grinders kick out an awesome amount of power, and don’t have the sort of safety features usually found on wood saws. The Graff website claims this blade is safer than attaching a circular saw blade to a grinder, though that’s hardly surprising, as the alternative is ridiculously dangerous. One key difference between this and a circular saw blade is that Graff’s is designed to reduce kick-back.

On table saws (which use a circular spinning blade similar to this), kick-back is where the object being cut is rapidly thrown at the operator. In chain-saws (used for carving in a similar way), it’s where the blade jams and rapidly accelerates towards the operator’s head (hopefully with the chain brake activating). In reality, these are both the same event – the blade jams in some way and as it can’t cut; it instead converts its energy into motion, either of the saw or the object being sawn. As you’re probably going to be using this on an object that’s securely clamped down, the risk is that the saw is rapidly accelerated in the direction opposite the spin of the wheel. We didn’t experience any kick-back, but it’s prudent to hold the grinder so that you can brace against this type of kick-back, and position yourself so it won’t meet your head if it does happen.

Before you even consider switching this on, you’ll need work gloves, safety goggles, and a face mask. This blade kicks out a lot of high-velocity sawdust in almost every direction (it seems to curl around the grinder guard to come right into your face at any angle, and blasts into your knuckles). You will need your angle grinder guard, and we can’t recommend using it without the handle attached on your grinder.

Because of the size of the blade, you’re quite limited with the angle of the indentations you can achieve

The SpeedCutter can be used as a saw. It absolutely rips through wood up to about 4 cm thick, (depending on the clearance of your angle grinder). However, it lacks an application where it would be a good saw. It can’t cut curves, yet the form factor of the grinder also means it’s hard to cut really straight lines. There are better, more suitable, and safe saws available for any application we can think of.

Artistic destruction

Arguably, the SpeedCutter’s most useful woodworking feature is its ability to carve out wood. You can glide the blade over the surface to skim off bits of wood in any direction. It’s unlike any other tool we’ve used. It’s almost half-way between a regular angle grinder cutting disk and a grinding disk, except this is for wood (and can also cut plastic and aerated concrete) and capable of removing far more material. Each pass can easily carve out several millimetres of wood – go any deeper and the blade starts to pull in the direction of rotation. Holding the tool securely in both hands, this pull isn’t strong enough to feel dangerous, but it is enough to pull the blade slightly out of line, and can cause your carving to go awry.

It’s more like chain-saw carving than anything else, so it’s not surprising that it’s popular as a power carver, though it could be used to cut out larger wooden joints if you’ve got a steady hand.

The most disconcerting thing about using the SpeedCutter is that it cuts so cleanly that it’s almost impossible to feel whether it’s engaged with the wood or not. With most carving tools, you can feel the wood under your tool, but this just glides through it and suddenly there’s air where the wood used to be. It feels a bit surreal to carve like this, especially with something as tough as wood. It’s almost like trying to carve air. We found it took a little while to get used to – as we had a tendency to keep pushing until we felt the blade engage, but by this point, there was already quite a lot of wood missing. This tool is hugely powerful, so it’s a bit surprising that it needs a delicate touch to get good results. Compared to chain-saw carving, it feels dainty and precise.
We found that the SpeedCutter left a cleaner cut in some directions than others, due to the way the blade sliced through the grains (in some directions, the surface of the wood remains smooth; in others, it splintered slightly). This sort of finish is to be expected with a tool of this cutting power, and adds to the power-carving aesthetic.

Simple designs, such as mushrooms, can be created in a matter of minutes

The tool’s big limitation is its form factor. Angle grinders aren’t really designed for this sort of work, and the basic shape of the body can cause problems. If you’re trying to carve out deep, narrow parts, the grinder can get in the way and, because you’re using a disc 115 mm across, you’re limited to the shapes of the depressions you can carve. Of course, every tool has its limits, but if you plan your designs well, your ambitions shouldn’t be held back too much.
This isn’t a particularly safe tool and needs to be treated with respect; we’d only recommend it to experienced power-tool users.

However, there aren’t any safe tools for power carving. The very nature of the hobby means you’ll be moving around something capable of easily slicing wood. The alternative is a chain-saw and we wouldn’t recommend a web search for chain-saw injuries while you’re eating. If you’re used to handling powerful tools, the Graff SpeedCutter is a fun way of turning some scrap wood into artwork.

Graff $18.60 speedcuttergraff.com


Simple designs, such as mushrooms, can be created in a matter of minutes