Double action OTF trapdoor

[wi-collector]

Very seldom seen out the front trap door switchblade knife. double action the large coil spring opens the blade and the smaller one closes it. all screw assembly. first knife to appear in the 1970 movie the cross and the switchblade. I've owned two of these but sold the first one which I always regretted but was fortunate enough to find another after 5 long years of searching e-bay. I doubt they made many before it evolved into the later model with the single spring opening model that came after it also minus the trap door.

[Bartlow]

That is an amazing contraption inside. Wow. Thank you very much for the pictures. Do you know anything on maker, designer, where made? The blade looks like it says something but I can't make it out. What are the markings, if any?

[wi-collector]

Its Italian and the blade is stamped Patent Rostfrei but I've also seen them with the Virginia stamp also. my favorite thing about this knife is the inside mechanism and how it evolved from this to a simpler design with the single coil spring.

[wi-collector]

screen shot of starting scene in the movie.

[QTCut5]

Very seldom seen out the front trap door switchblade knife.

Very cool Great pics....love seeing the guts I've never seen an OTF with a "trap door".....how does that work exactly? Do you have to manually open it or does the tip of the blade push it open upon deployment? What about closing it....manually, I assume? When it's open, how loose is it? Seems like it would have a "flopping" movement that would be annoying

[wi-collector]

it's pushed open when button is pushed forward then manually pushed closed after retracting the blade. the trap door is under spring pressure when opened by small coil spring in a cavity in the front bolster. check photos as it shown in one photo.

[JulesVane]

VERY COOL!

[BestVintageKnives]

Nice. I have the patent design for the trapdoors. Thanks for sharing.

[wi-collector]

this is the first one I had which I sold not in nearly as nice as the one I have now. both examples came out of Florida sold by different sellers on e-bay about 5 years apart

[Bartlow]

Nice. I have the patent design for the trapdoors. Thanks for sharing.

Does it list the designer for the idea? The company that made them? I have no idea what Italian patents include in terms of information. I think these are amazing gadgets, especially contrasted with the utter simplicity of a spring open knife where the blade comes open automatically from the side, but of course has no mechanism for closing the blade except manually.

[BestVintageKnives]

Nice. I have the patent design for the trapdoors. Thanks for sharing.

Does it list the designer for the idea? The company that made them? I have no idea what Italian patents include in terms of information. I think these are amazing gadgets, especially contrasted with the utter simplicity of a spring open knife where the blade comes open automatically from the side, but of course has no mechanism for closing the blade except manually.

Yes, there were two people who designed the trap doors and for the design there’s at least five different drawings showing various parts of the mechanism

[SwedgeHead]

My mother and her friend took six of us as kids to the drive-in to see The cross and switchblade. Not the most kid friendly movie but that was how we rolled back then. (in a Pontiac station wagon) I still have a picture in my mind of a guys guts spilling out after a gang fight. You never hear reference to the movie so I had to comment, and that's a cool knife too !!

[SwedgeHead]

Ha, I had to Google it again. Never even knew Erik Estrada was in it.

[BestVintageKnives]

My mother and her friend took six of us as kids to the drive-in to see The cross and switchblade. Not the most kid friendly movie but that was how we rolled back then. (in a Pontiac station wagon) I still have a picture in my mind of a guys guts spilling out after a gang fight. You never hear reference to the movie so I had to comment, and that's a cool knife too !!

Yeah, same here. The neighbors took all of us to see the movie on an old 16 mm movie projector at a church one weekend that’s the first time I ever saw a switchblade. I was about 10 or 12. That was probably about 1982.

I guess I chose the switchblade over the cross, lol.

[QTCut5]

The cross and switchblade. Not the most kid friendly movie

Believe it or not, I actually read the book and did an oral presentation book report on it when I was in eighth grade in 1978 (I was hoping it was more about switchblades than it turned out to be ) I wonder if it would even be allowed in any school libraries nowadays.....probably not.

[BestVintageKnives]

Nice. I have the patent design for the trapdoors. Thanks for sharing.

Does it list the designer for the idea? The company that made them? I have no idea what Italian patents include in terms of information. I think these are amazing gadgets, especially contrasted with the utter simplicity of a spring open knife where the blade comes open automatically from the side, but of course has no mechanism for closing the blade except manually.

I’m happy you asked. I took a look and wow the original design has “S” shaped guards. How cool.

I’ll have to give you credit for this.

Back 25 years ago everyone said the Italians just drank wine every day and made junk knives, sh*t knives, etc. I’ve found in searching for the paperwork it’s 100% the opposite. They were incredible designers and trained craftsmen who trained in schools and got diplomas for their craft. They took care to do it all right. Designing knives and manufacturing them and marketing them around Europe and the USA and all other far away places for over 100 years. All done before computers and the internet. Everything post 1975 is really just a copy and remake (and there is nothing wrong with that) of the what the true Masters made.

[QTCut5]

What's the purpose of the 'trap door' feature?

[wi-collector]

on a OTF style knife it very important to keep dirt and pocket lint out of the mechanism to prevent stoppages I think they achieved this by adding the trap door to correct this problem and is the only reason it was there that I can think of.

[BestVintageKnives]

on a OTF style knife it very important to keep dirt and pocket lint out of the mechanism to prevent stoppages I think they achieved this by adding the trap door to correct this problem and is the only reason it was there that I can think of.

Good observation. I agree.

[BestVintageKnives]

Your knife is probably several years older than this catalog cut. This is a 1975 C. Jul. Herbertz catalog. I know tons of the trapdoors that surfaced the past 5 years were marked Herbertz.

[wi-collector]

I've had a few examples of the one in your catalog and I'm sure as you said mine is several years older as the movie dates to 1970. these later examples have been showing up for sale lately with cast metal buttons but are different by not having screw's or the swedge blade which is slightly longer on my knife plus it also has a single spring to preform both functions of opening and closing the blade although the spring is much thicker than modern super automatic, NATO or concord style current production OTF's .

[1967redrider]

Thanks for showing the inner workings. Those Chinese Lightning OTFs work the same way.

[wi-collector]

I never seen any other OTF that used dual springs one to open and another to close the blade and I've had thousands of them apart from all different parts of the world the only other weird opening model is that French OTF that operates backwards on the button it has a sort of torsion bar that swats the blade open very odd mechanism

[1967redrider]

I never seen any other OTF that used dual springs one to open and another to close the blade and I've had thousands of them apart from all different parts of the world the only other weird opening model is that French OTF that operates backwards on the button it has a sort of torsion bar that swats the blade open very odd mechanism

Check this out-

https://www.allaboutpocketknives.com/kn ... 60#p863961

[wi-collector]

it has dual springs, but they only open/close the blade from one single source this one I have each preform only one task per spring the larger cone shaped one only propels the blade open while the smaller coil only retracts the blade.