How Does an OTF Knife Work? | In-Depth Demo

[@SparkyMTB]

I’ve watched 6 videos on this subject today (how does an OTF knife work) but your video has the best explanation, thank you 👍🏼

[@ThumbStuds]

Thank YOU! I appreciate the comment

[@nabins52]

Jeeze, lots of videos trying to explain on here but not one is concise enough to make any sense. Yours however was to the point and super informative. Understood the mechanism. Thank you!

[@ThumbStuds]

Thank you for this comment and I'm glad the video was informative!

[@dougvail7005]

I found a microtech OTF knife in bad shape and wanted to fix it. It was different than the knife in your video but your explanation was so thorough I was able to understand the fundamentals of this design. I was able to dismantle, clean and repair the knife. Thanks to you I have a cool EDC knife. Keep up the good work.

[@bozmeg6918]

Thanks ! Last video I saw did not explain how the spring works. You have the ability to explain in detail how it works. Thank you.

[@dondee5439]

So basically the two springs (some OTF knives use only one spring) are under some stretch tension all the time. Moving the thumbswitch adds some more spring stretch tension and releases the little catcher tabs on either end and the blade slides either forward or backward. Pretty smart idea making a spring do work in either direction. I just wonder how much thrusting force an OTF knife can withstand before the blade collapses back into the handle. Seeing the guts of the OTF makes me think of a glorified utility knife for some reason. I guess it is like seeing the sausage being made. Great job on your video here.

[@ACommenterOnYouTube]

Correct, 1 spring is under tension when the blade is in and the other spring goes under tension when the blade is out.

[@Jacob-ol3zb]

I'm so happy I found your video. This was an amazing explanation. I had tried other videos first and they didn't explain it that good. This video is the one that actually taught me. Thanks for taking the time to explain this!

[@itztwoost2744]

I was curious what this extra spring was for that came with my otf knife so I was an idiot and disassembled my knife and it took me a good 20 minutes before I found this video and was able to put it all back together. This video saved me so much time, thanks!

[@Arrowed_Sparrow]

Thank you for the easy to follow explanation. The mechanism is actually more simple than I thought.

[@aliciamitchell2055]

I just bought my first otf and I love it. Your video is very cool. Thank you.

[@Nefville]

Thanks. I just got a Lightning OTF, the older version, and I was wondering how that works so easily. I guess it doesn't take a lot of force from your thumb to move a blade in and out, but it does kind of seem like magic.

[@NonEuclideanTacoCannon]

Found a Benchmade OTF on the side of the road a while back, and I loved that thing. I basically used it as a glorified box opener, but it was extremely handy and I used it every day. Then it started getting stuck open. Took it apart, thoroughly cleaned it and hit it with dry lube. Still gets stuck out. Thought about buying a new one, then I saw the particular knife I have is like $400. I was hoping to glean some insight as to why it would close normally, but I'm still stumped.

[@Redoctober81]

Send it into Benchmade , they will probably fix it no questions asked.

[@AltaSurvival]

Great job explaining the functionality!!

[@jeffcanfixit]

GREAT vid!! I'm more of a folder guy (just 1 otf) but I've always been curious as to how they work. That was clear, concise, just well explained.. 👍👍🔪

[@stephenthomas729]

Defiantly the very best explanation thank you

[@yungmoosepiss994]

What a concise and clear explanation. Bravo!

[@Moltimer5050]

thank you for the explanation it was very clear and amazing

[@ThumbStuds]

Thank you! I'm glad you enjoyed the video

[@hollow_guy_]

Awesome vid. Everything is explained really clearly and makes sense 10/10

[@jadams2013]

Very good demo! Thanks!

[@jordanhanlin8371]

I have one of these knives and it is by far my favorite out of all my knives I now see how it works n is pretty badass thanks for video

[@Life4YourGames]

Very nicely explained and easy to follow. Thank you! :)

[@tranxoo2501]

u really explained it very well

[@ThumbStuds]

Thank you, I glad you found it informative!!

[@jeffgough]

Great video. Would love an explanation of how the blade stops if it encounters an obstacle / resistance while opening though. That’s an excellent safety feature of these OTF knives and always perplexing. Is it because it has forward momentum from the spring while opening but doesn’t reach the detent to “lock it open” so it just stops the momentum?

[@ThumbStuds]

Thank you! I have a short video on explaining just that, it's titled "What happens if an OTF knife OPENS in your POCKET!!" hope you find it informative!

[@jeffgough]

@@ThumbStuds Thanks for responding. I watched your video short on OTF knives opening in your pocket. But it doesn’t explain *why* it stops itself. I’m guessing because the spring launches it forward but it never reaches full lock out at the detent so it is stopped by whatever obstacle it encounters. Seem right?

[@stuartli16610]

Yeah, the power of the spring is pretty weak, if it hits an object it doesn’t have the force to keep travelling to engage with the detent to lock it in place. That’s why you can just fix a not fully opened OTF by pulling out the blade and let it engage with the detent and it will work again.

[@the-sassy-blacksmith7594]

Thank you man ,im working on making an assassins creed hidden blade and am hoping to use this mechanism

[@matthew8455]

Nice video you really helped me understand how the knife works. there really hard to get here in canada I was very curious how it works and I don't wanna take mine apart an risk braking it or something

[@69CamaroSS]

Applying years of gun smithing, race engine building and machine shop experience…….it seems only logical that IF one was to mirror polish the contact surfaces on the plate and the detents, the “trigger pull weight” can be dramatically lessened on these which would provide a much lower amount of pressure necessary to be applied to the thumb switch in order to fire the knife! 🤔🤔

[@simartnullnet]

Excellent explanation

[@elihorn9525]

How are the detent springs installed? Are they just wedged between the body and the detent or is there some kind of mechanical connection?

[@unidentifiedbiomass4106]

not as complicated as I thought it would be, still whoever figured this out is big brained

[@vtxdaryl]

Excellent explanation,thanks.

[@markswishereatsstuff2500]

The Lightning OTF is a great knife for the money. I have a Microtech that is impossible for me to retract so I don't use it. Deploying it is no joy either. Lightning for the win.

[@evv.n1211]

Can one in theory create a circular one with transparent cylinders as a blade, complete with lights and speaker?

[@C_Hart]

saved my knife! thank you

[@jwmonke]

My spring on my otf is always derailing/stops working, it’s brand new and I used it once, in and out. Then I go to try it again and it doesn’t come out anymore. I opened it up and “fixed it”. It worked then broke again the Same way. What can I do?

[@isrulius]

Get a knew knife unfortunately. Sounds like the item is defective.

[@Faer0512]

06:02 That's one word is enough to explain the entire mechanism about how it works (*anyway I'm a homemade knife too )

[@BPEMETO]

Very useful video! Thank you! : )

[@EkoTube]

Can it somehow fly out or is that not possible

[@VidarrKerr]

You edited out the part where you cut your thumb.

[@PtaqMaster]

thanks ! now i can buy one =}

[@dmitriibannikovasx]

Assassin's hidden blade mechanism)))

[@TheBestgoku]

thank you.

[@kimobugman]

Now can you demonstrate how resetting the blade works

[@crewcutter2030]

Ok, now how do we customize it to work like the assassins creed hidden blades?

[@kalazardonovani8275]

Thanks

[@ripphunter8872]

Fucking marvelous engineering

[@scottschoppert9149]

I don’t understand how the spring tensions itself when the blade doesn’t get deployed

[@nabins52]

That’s the point - the sprint isn’t tensioned when not deployed. You start moving the slider and only then it starts tensioning. It won’t deploy because it’s stuck by the detents. Once the detents are depressed by the metal plate the loaded springs fling the blade to the other side.

[@scottschoppert9149]

@@nabins52 that makes sense because I put something in front of my stepdads knife to see what happens when it doesn’t get fully deployed and it wouldn’t retention and I thought it was broken but after a few times redeploying it it was working again. So you are saying that the actual detent holds the tension?

[@dondee5439]

The spring/springs are ALWAYS under some slight tension in either the open or closed position. Moving the thumbswitch adds even more spring tension and releases either the forward locking tab or the rear locking tab and the blade is flung in the right direction. Pretty cool fooling a spring into working both ways by always being under tension.

[@akibee6789]

Out the front more like out “tender” front

[@Mr-pm3jp]

1:36 "when this slides FORD" 1:43 "blade to move FORD"

[@VidarrKerr]

He clearly says "Chevy".

[@ryanorionwotanson4568]

You cut yourself with the knife? Thats what im worried about...😕