What is a spring assisted knife?

Even if you’re really into spring assisted knives, chances are you don’t know much about their background or history. In face you may have even found yourself thinking, “What is a spring assisted knife?” The truth is, I didn’t really know much about the history of spring assisted knives either until just recently, and it’s pretty interesting. Take a look at the history and mechanics of spring assisted knives.

Kershaw Leek

History of Spring Assisted Knives

Interestingly enough, the research I did suggests that automatic knives were invented much earlier than spring assisted knives. I, for one, thought that automatic knives would have been made first since they seem more technical to make. However, automatic knives and spring assisted knives are actually pretty similar as far as mechanics go, but I’ll go more into detail about that later.

The first spring assisted knife was designed by Blackie Collins. Collins passed away in 2011, but during his life, he was an amazing knifemaker. He and Bill Meyer teamed up to create the company Meyerco, but they also designed the first assisted-opening knife in 1995. Collins named the knife the “Strut’N’Cut” after his Ducati motorcycle, which had a single strut. The Strut’N’Cut won the “Most Innovative American Design” award at the 1997 Blade Show.

A few years later, knifemaker Ken Onion came up with a similar concept. Spring assisted knives gained a lot of popularity with the help of his SpeedSafe mechanism that you’ll find in the spring assisted knives Onion has designed.


What is a spring assisted knife?

I mentioned earlier that automatic knives and spring assisted knives are fairly similar. Automatic knives are opened with the help of a spring, like spring assisted knives. With automatic knives, all you have to do to deploy the blade is push a button, and the spring fires the blade for you.

Spring assisted knives are constructed somewhat differently, though. Spring assisted knives do not open automatically, but must be opened to about 45° before the springs take over and finish opening the knife. When spring assisted knives are closed, the blade is held in place by torsion springs and sometimes also a lock. Then, when a thumb stud or flipper is pushed, the spring moves and deploys the blade.


Other Random Spring Assisted Tidbits

As we’ve stated before on the Spring Assisted Knives blog, spring assisted knives are typically legal in more places than automatic knives. For that reason, they can be a more attractive option when choosing a knife because they’re not as restricted as automatic knives (although they’re more restricted than manual knives). They also have very speedy opening that’s right up there with the speed you get from automatic knives. So, with spring assisted knives, you get speedy opening that is legal in more places than automatic knives. Win, win.


So what is a spring assisted knife? I hope we’ve been able to enlighten you, but if you still have questions, let us know in the comments section below!

At  Blade HQ, we’ve got a pretty great selection of spring assisted knives, including the latest releases from your favorite manufacturers.

Is there anything else you want to know about spring assisted knives? Are you in need of a recommendation for a good spring assisted knife? Let us know in the comments section!

Kershaw Leek Composite


You know the Kershaw Leek. You might even have one in your pocket right know. You’ve probably never seen a Kershaw Leek quite like this one before though: This is the Kershaw Leek Composite. The whole knife, blade and handle alike, feature Kershaw’s BlackWash finish. This Leek has a 3-inch blade that’s made of Sandvik 14C28N and D2 steel. The overall length is 7 inches … Continue reading

CRKT Cobia Matthew Lerch Spring Assisted Knife


If you’re really on top of things in the knife world, then you know BLADE Show just happened. Shot Show happens in January and that’s where manufacturers typically showcase most of their new product for the year. However, BLADE Show is obviously more geared toward knife manufacturers, and there’s still some new product that’s released at the show. This year, there was actually quite a … Continue reading

Limited Edition Benchmade Mini Barrage – New for 2014


You’re probably already familiar with the Benchmade Mini Barrage, but this is a new, limited edition Mini Barrage that’s pretty awesome: This Mini Barrage is new for 2014, and it’s got all of the nice features you’d expect to see in the Mini Barrage—like the AXIS locking mechanism—but its handle is a little bit different than what you find on the original Mini Barrage. On … Continue reading

H&K Nitrous Blitz


The H&K Nitrous Blitz is a pretty sweet spring assist. Honestly, my favorite thing about this knife has got to be the swedge—it looks sick, and it sets the knife apart from your normal everyday folding knife in terms of looks. In terms of function, though, the Nitrous Blitz is equally amazing. The knife uses a “spring assisted Nitrous mechanism” that is “built directly into … Continue reading

Zero Tolerance 0770


I don’t think I’ve met a knife enthusiast who doesn’t like Zero Tolerance. Zero Tolerance knives are extremely tough and functional, and when you pair that with a great design, you’ve got yourself a pretty amazing blade. While I’d say that ZT makes more manual folding knives than anything else, the company also makes some really great spring assisted knives. Some of them you’ve already … Continue reading

Teal Kershaw Leek


We just got this new Leek in at BladeHQ: (Image from Instagram. Follow us!) You’re probably pretty familiar with the Kershaw Leek, so I’ll skip over most of the specs. All you really need to know is that like all Kershaws, the Leek is a terrific bang for your buck. It has excellent action and materials, and it’s a great option for your everyday carry. … Continue reading

New BlackWash Kerhsaw Knives


I know you’ve probably had your fill of SHOT Show updates, so this will be the last one for a while. I’ve already covered several new Kershaw blades for 2014, but there are a few more I wanted to show you. BlackWash seems to be Kershaw’s new finish of choice for this year, and can you blame them? BlackWash looks particularly awesome, and it’s featured … Continue reading

New!: Kershaw Camber


The Kershaw Camber is another new knife you can look forward to in 2014! The Camber has a stonewashed premium S30V steel blade, so it has great toughness and wear resistance, but the hardness is also quite good. The overall length comes to 7.20 inches with a 4-inch handle and a 3-inch blade. The aluminum handle has great texturing that provides a secure grip, and … Continue reading