We have a secret project underway at PTR Labs, also known as “The Shop” to just about everyone else. It really is a secret project, so no, I won’t be dropping any hints. I’ve told you too much already. Part of this project is right up my alley: metal cutting. As part of our project, we’re testing several top metal cutting chop saws, abrasive cut off machines, and metal cutting blades. Abrasives are so 2010. On the other hand, the Milwaukee 14-inch Steelhead Diamond Cut Off Blade hit the scene as an alternative—a freakishly effective alternative.
Cut Life and Durability
Milwaukee claims their Steelhead blade will last up to 75 times longer than standard bonded abrasives. I’ve done plenty of cutting with bonded abrasives and I have no desire to spend the amount of time it takes to actually test that, but Milwaukee did let us in on some internal testing results. Using 25 gauge steel studs, they got between 6 and 13 cuts out of standard abrasives.
The Milwaukee 14-inch Steelhead diamond cut off blade?
Of course, we have to note that this was a controlled test done by Milwaukee folks, but every time we’ve repeated a test they’ve done in-house, our results were awfully close. While there may be some slight variance if you try this at home, it’s likely to be well within statistical confidence levels.
What’s the Difference?
To get this kind of durability from a blade, something has to be drastically different than the traditional abrasive. Milwaukee uses high-grade synthetic diamond grits along the cutting edge. Rather than being bonded with a metal mixture the way masonry blades are designed, these diamond grits are exposed.
Thanks to the diamond grit design, you won’t lose the diameter of your blade like you do with abrasives. As the blade wears out (like all eventually do), it’s the diamonds that will have been stripped away rather than the steel blade itself shrinking.
One of the big safety risks with abrasive blades the their ability to break or crack during use. At speeds of 4000 RPM and higher, that doesn’t end well. Milwaukee’s steel core blade doesn’t suffer the ill effects of failure from wobble and deflection that way.
Milwaukee 14-inch Steelhead Diamond Cut Off Blade Performance
So the design is clearly different from abrasives, and that has a big effect on longevity, but how well does it cut? Before taking the blade to cutting steel pipe on the frame of our secret project, we really needed to know what kind of cutting characteristics we were looking at. We installed the blade on our Ridgid 14-inch Abrasive Cut-Off Machine and put it to work on some stock angle iron we had laying around.
The abrasive disk that came with the saw cut as expected, throwing plenty of heart pumping sparks and taking its sweet time to make it through. It’s a slow, smooth process, but we’re grinding away metal, what should you expect?
Testing the Milwaukee Steelhead 14″ Diamond Blade
We spun up the saw with the Milwaukee 14-inch Steelhead Diamond Cut Off Blade on and noticed a remarkable difference in cutting speed. Once the blade made the initial entry into the iron, it seemed to laugh at the iron’s attempt to stop it through friction as the diamonds blazed a path through. It wasn’t quite a hot knife through butter fast, but it was much faster than the stock option.
This isn’t a blade that eliminates sparks. In fact, we noticed an increase. They also were able to escape out the side more compared to the reasonably controlled abrasive disk. That may be due to the fact that the blade was removing material at a faster rate. No matter the reason, be sure that you’re wearing all the appropriate safety gear when using this (or any other) blade.
We did find a slight amount of burring along with a little slag on our cuts. It’s a significant improvement over the stock abrasive blade, though.
The Milwaukee 14-inch Steelhead diamond cut off blade is indeed an outstanding alternative to traditional abrasive disks. Based on our limited testing and the internal testing at Milwaukee, you should get a tremendously long life out of the blade. Our performance testing definitely resulted in much faster cutting speeds over abrasive blades. The increase we saw in sparks is likely due to the increased rate of material removal, but calls out the need to have protective gear in use.
Cost is going to be the main stumbling block for most professionals looking for a replacement blade. Online prices for Milwaukee’s premium blade are running around $160. With an abrasive cut off disk going home with you for $10 – $20, that can be a lot to swallow. Still, even on the low end, 75 abrasive disks will cost $750—a whole lot more than $160 to make an equivalent amount of cuts. Milwaukee’s Steelhead Blade is definitely a pro-level accessory that comes at an excellent value compared to traditional abrasive disks.
Milwaukee 14-Inch Steelhead Diamond Cut Off Blade Specifications
- Model: Milwaukee 49-93-7840
- Diameter: 14 in.
- Arbor Diameter: 1 in., 20 mm
- Blade Material: Steel core, diamond cutting grits
- Max Speed: 5500 RPM
- Rated Materials: Metal, including stainless steel
- Price: $84.99