I didn't want to hijack Carson's thread in the photo section, but I'm just curious. How do double actions actually work; particularly the Benchmade 3800? I saw a video on YouTube, but what I don't get is how there isn't any tension when opening and closing manually but all of a sudden the spring is fully loaded when using the auto function. I would love to see an exploded view of one of these.

There's a leaf spring that sits against the backspacer. The button keeps spring wound up. When spring is released it just pushes the blade out.
Hope that makes sense.

quote:

Originally posted by RxEnergy:
There's a leaf spring that sits against the backspacer. The button keeps spring wound up. When spring is released it just pushes the blade out.
Hope that makes sense.

Thanks. Yeah, that kinda makes sense. So, does that mean there would be tension when closing if it was opened using the auto function?

Yes. Only if it was opened in auto mode.

Rx explained it really well. The leafspring pops the blade open if the knife is closed when you actuate the button.

If you actuate the button while the blade is already open, it makes a very sick sound and you get a sick feeling in your stomach hearing it. It will pop the spring, but there's no blade there to propel open. It's a very disturbing feeling. I know this thanks to a coworker who's lucky he didn't eat a knife that day.

If the spring has been sprung, just close the knife to reset it. On some of them it is very stiff and you practically have to ball up your fist to close the knife. I am a big fan of scale-release double action automatics. Have a look at something like the Lone Wolf Lobo to get an idea of one.

Thanks guys. I completely understand now .

Yep. They are fun to play with!
I have a LW Diablo scale release D/A and Brad Duncan's button D/A Whiplash. Diablo works great for Los Angeles carry since it's under 3" and it has a very discreet auto release. Pocket clip sucks for jeans carry though (too close to handle)

Maybe BM will make one under 3" one of these days so I can get in on the fun.

They are bringing a Diablo to the HK line

Double checked and it's 3.16". Close enough

http://www.benchmade.com/products/14925-14975