Hole saws are one of my most hated tool accessories. They're slow, clunky, and a pain in the ass to take out the core. They drain my cordless drill batteries faster than I can recharge them. Spyder comes out with the Rapid Core Eject Hole Saw System that we reviewed a few months ago. The innovation they bring to these accessories is a breath of fresh air. A new hole saw installation and coring system brings new life to the hole saw market.
Now let's take a look at the Diablo Snap Lock hole saw system. This too has some new innovations and promises greater depth of cut, faster cuts with less vibration, tool-free core ejection, quick hole saw replacement and, of course, technology added for the extended life that Diablo is known for. Diablo innovates in a slightly different direction than Spyder. However, since Diablo isn't used to being second to anyone in performance, I'm excited to see what this system has to offer.
Learn about the Diablo Lockhole Saw System
Diablo Bi-Metal Hole Saw
Diablo did some thinking outside the box when developing its new Holesaw lineup. When you pick up a Diablo Spring Lock Hole Saw, the first thing you'll notice is the length. These saws are 60mm (2.36 inches) compared to the 40mm standard of other saws. This length should be enough to cut 2x the material already attached to the sheet without having to switch sides to complete the cut.
Variable tooth geometry is one of Diablo's specialties. I like the fact that engineers are not only looking at materials, but tooth angles and combinations of angles that allow for faster cutting and less vibration. These HSS (High Speed Steel) bi-metallic blades are available in diameters from 5/8" to 6" and cut a wide variety of materials:
- Wood: up to 2400 RPM
- Aluminum: 345 RPM max
- General Metal: 230 RPM max
- Stainless steel: maximum speed 115
You'll also notice that the slots on the Diablo snap lock hole saw protrude much more than other slot saws. This should result in better cooling, help with dust removal, and help get stuck cores out. While I don't think you'll have this problem very often, if you're cutting wet wood and the saw gets hot enough for it to expand, the core can expand inside the hole saw.
Diablo Spring Lock Arbor
The Diablo Snap Lock Mandrel is simply amazing. The replaceable pilot bit is installed by pushing it into the arbor chuck. The chuck is designed exactly like an impact driver, so the bit locks into place. There is no need to remove the mounting mechanism as some chucks require. The same goes for installing hole saws. Simply pull it down until the saw snaps into place. Just like your impact driver chuck, you can remove the hole saw and/or replace the pilot bit by pulling down on the chuck mechanism.
Diablo has thoughtfully included a pair of hole saw adapters with Snap Lock Mandrel. These come in 1/2" and 3/8" sizes and should work with most other hole saws on the market if you wish. While I'd love to tell you there's really no reason for this, it's not entirely accurate. More on that later.
In addition to quick hole saw changes, another purported benefit of the Diablo Snap Lock Mandrel is faster core ejection. In theory you should be able to eject the saw, core and all, then use the pilot bit at an angle to poke the core out. We'll definitely take a closer look.
Diablo locksaw system at work
I love, love, love having a hole saw on this system! Simply snap the desired size onto the mandrel and you are ready to go. Every other hole saw I've used requires you to screw it onto the arbor. The Spyder's system locks it in place when tightened, whereas other systems force you to secure it by tightening the saw at both ends. The Diablo Snap Lock hole saw system gets a head start before you even start drilling. Likewise, changing a hole saw is very easy. I got a hole saw in 4 diameters to test and it took less than 10 seconds to rotate between all four sizes. Granted, this is without cores to remove, but it's still pretty fast!
I decided to test the Diablo Snap Lock Hole Saw System with 2x pressure treated lumber affixed to an OSB board. This is a fairly typical application, and since most hole saws can't cut through two pieces of wood, you can double the cutting time. The Diablo's 60mm height allows it to pass through both pieces with a little room.
How about the cutting speed? It is very strong. It was a bit quicker than other performance hole saws I've used when cutting through pressure-treated lumber. Of course, the real advantage came when I hit the OSB plate. Every other hole saw I've tested required me to stop, remove the core, and continue drilling. I did notice that the grooves do an excellent job of helping remove sawdust from the cutting process. I seemed to be running cooler than the others to start with, but it did start to smoke. In one test I even got some pretty thorough burn marks on the OSB.
Core removal gets interesting. Spyder introduced their Core Eject System a few months ago, and it works pretty well for the most part. The Diablo Snap Lock hole saw system is a little different. The Spyder's system allows you to pull the hole saw down, exposing the core. Then you simply pull the core off the pilot bit. Instead, the Diablo's snap-lock system lets you separate the hole saw from the arbor. From there, you can push the core up with the pilot bit and pull it out by hand. On the surface, Spyder's system appears to be a bit cleaner. In fact, both methods are pretty close in terms of how quickly I can consistently remove cores. At this point, I'm not sure I can definitively say one is better than the other.
Interestingly, the retainer bearing that holds the pilot bit in place failed on me. Since you need to hold the drill in place, it's not only a little inconvenient to have it slide out easily during coring. I've talked to the Freud people about this, and my experience is the first they've heard. After receiving a pair of replacement arbors, I tested them for live daylight and was unable to reproduce the failure. I put that down to an isolated incident.
The Last Word on the Diablo Spring Lockhole Saw System
I was happy to see the extra hole saw adapter nut that came with the arbor. This means I can use a tungsten carbide tipped hole saw with a Diablo arbor and cut through wood at lightning speed. While this is still a good idea, be warned. The torque that drilling with a hole saw can provide, especially for larger diameters, can keep the nut snug against the hole saw. I haven't loosened it yet, though I'm being a little gentle so as not to damage the hole saw cutting teeth.
Do they work as Diablo claims? Certainly looks like it to me. These have the absolute fastest setup and hole saw variation I've gotten my hands on. Coring is a big step forward from having to pry it out of the side slots, on par with the Spyder. Cutting speeds on par with other high performance hole saws. The ability to cut 2x material and one plate is a big win for the Diablo. There's also the fact that the Permashield allows it to cut that deep without binding the bit.
This is definitely a system I would recommend to a professional. My only (and slightest) hesitation is to see if the retaining bearing issue recurs. However, I don't think it's prudent to pay attention to other user reviews. The Diablo Snap Lock Hole Saw System isn't in stores yet, but a handful of online retailers claim to have it in stock. As always, Diablo products come with premium prices attached. The online prices I've seen (which don't always reflect what the brick and mortar store sells) range from a little under $6 for a 5/8" hole saw to about $25 for a 6" hole saw. Personally, I'd wait until they're more readily available before pulling the trigger and seeing where prices settle.
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