Case 6172L

[Bill DeShivs]

The blade was badly stamped with individual letters, apparently.

[iDroolT]

The blade was badly stamped with individual letters, apparently.

by whom? fraudster or factory?

[BestVintageKnives]

Looks tampered with & suspicious to me, i’m no expert but can’t wait to hear from the others here.

Does the pivot pin look okay?

[1967redrider]

It's hard for me to tell if the stamp isn't uniform or if it is running uphill (so to speak)? Cold stamped or worn from opening/closing? Original pin?

[BestVintageKnives]

It's hard for me to tell if the stamp isn't uniform or if it is running uphill (so to speak)? Cold stamped or worn from opening/closing? Original pin?

If the blade isn’t original where is the blade from?

I’d not want to be responsible for giving bad advice and ruining the value of someone else’s knife…

[stockman]

Has anyone tried a little oil?

Harold

[BestVintageKnives]

Has anyone tried a little oil?

Harold

[iDroolT]

Is the pin suppose to be nickle silver, brass or steel? She didn't say whether she'd ever oiled it. I know I haven't. The locking mechanism works fine it seems, just the automatic action is too weak to shoot the blade out I believe. Looks pretty rusty inside from what I could see. Tell me what you want me to do and I'll do it. Type of oil? I always used old 3in1 on my carbon blades.

To me it looks like the letters are running uphill but I dunno.

Does anyone know how many of these knives are known to be in collections and documented? Im curious whether there are any examples with stamping done this way during manufacturing.

[BestVintageKnives]

Is the pin suppose to be nickle silver, brass or steel? She didn't say whether she'd ever oiled it. I know I haven't. The locking mechanism works fine it seems, just the automatic action is too weak to shoot the blade out I believe. Looks pretty rusty inside from what I could see. Tell me what you want me to do and I'll do it. Type of oil? I always used old 3in1 on my carbon blades.

To me it looks like the letters are running uphill but I dunno.

Does anyone know how many of these knives are known to be in collections and documented? Im curious whether there are any examples with stamping done this way during manufacturing.

Yes just a couple drops of 3-in-one. Bet it will fly open. If so leave it as is

[btrwtr]

The color of the blade pivot pin looks like it might be steel rather than nickel silver which would be the correct material. If it is steel that would mean at very least the blade has been re-pinned at some point in the past. You might be able to tell if it's steel with a good magnet. You have some good advice here for repairmen and I believe the knife would be better if repaired by one of the competent guys mentioned. The handle could also use some competent repair. A good repair won't be cheap but it's not a cheap knife. Selling the knife as is would still bring some very serious money without the logistics and dollars that a repair would present.

[btrwtr]

I believe that anyone that would have the skill to cobble up a blade for replacement would also have the skill affect some repair to the knife and that obviously hasn't been done. Everything about it looks correct with the exception of the pivot pin and I would like to see a pattern number on the back blade tang. If a person could cobble and stamp the blade they could just as well provide a pattern number. If the pin is NSL then you can scratch that issue. Other than the wear on the knife I can't say that I see anything wrong with it. Looks all original to me just looking at the pictures provided.

[Killgar]

I see a few other Case 5172L's online.

There's a youtube video of one, It's marked "XX" over "5172L" on the pile side of the tang (pics below). Video- https://www.youtube.com/watch?v=YXPnOdAhbs4

There's another on Worthpoint. The pictures don't show the tang stamps, but the description says "The model number is stamped on the backside of the tang "5172L". Link- https://www.worthpoint.com/worthopedia/ ... -415989622

The fact that the blade of the knife you posted has no nail nick leads me to believe that it was intended for a switchblade. Although many switchblades have nail nicks for different reasons, I'm specifically referring to the Case 5172's. All the manual Case 5172's and 6172's that I see have nail nicks, so that leads me to believe that the blade of your friends knife did not come from a manual 5172 or 6172.

I also noticed that the three other 5172L switchblades I've seen all have stag handles. Yours could just be an oddball with jigged-bone handles and no pile side tang stamp. Oddball, but still possibly authentic. Or, maybe Case made others just like. Either way, it's always possible your friend has an ultra-rare specimen.

As far as how many were made, I've read from different sources- less than a hundred, as many as fifty. But without official documentation or an official source from Case, how can one ever know for sure.

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Here's the third one I've seen lately.

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[BestVintageKnives]

Here another.. Same Bradford era stamp.

[iDroolT]

all very interesting. i really appreciate all of you spending some time to help us figure this out.

since the handle material was brought up i feel i should mention that my friend said one of the people she talked to about it before said that the most rare were those with green bone. i'm not sure who it was that told her that.

are there people that can "officially authenticate" these things? i'll do what i can with the suggestions you've offered. maybe a trip to antiques roadshow is in our future? i'm sure she'd get a kick out of that. lol

okay, i'll post an update after i hit it with a little oil and check the pin with a magnet. wish me luck!

[btrwtr]

since the handle material was brought up i feel i should mention that my friend said one of the people she talked to about it before said that the most rare were those with green bone. i'm not sure who it was that told her that.

Absolutely the bone handled version is much less common on this very uncommon knife. The stag version is much easier to re-handle and I would look harder at any version of this knife in stag. The handles on the OP knife are 100% correct.

[BestVintageKnives]

So it seems the stamp is 100% correct?!? Just odd there isn’t a rear marking on the ricasso. Maybe a prototype?

The bolster shows no file marks or damage around the pivot pin on either side

[iDroolT]

Very interesting stuff...Exciting! Pin looks to be steel. Magnet was strong enough that its able to reach through the nicklesilver into the internals but the pin is noticeably stronger so it has to be steel. Oiled it up, cleaned the inside a little with paper towel. Pretty dirty but the rust doesnt look too terribly bad. The spring seems like its been over sprung, will only pop out about an inch. Very weak. Maybe from people trying to pull it open manually that didn't know its an automatic? That would explain the blade peek for sure.

[BestVintageKnives]

Another I’ve seen.

[Killgar]

The one below appears to have jigged bone handles.

You can always contact Case and see what they say. I'd be surprised if they provided any information, but it's always possible. They have a phone number on their contact page- https://www.caseknives.com/pages/contact-us

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[iDroolT]

very nice examples and thanks for the suggestion of calling case. we'll do that.

[iDroolT]

the new information i have tonight after getting details is that she talked to a man in his 80s at a knife and gun show in early to mid 2000s that said he'd been collecting since he was 13 and had never seen one, gave her the name of collector jim sargent out of alabama and told her to contact him. she never did and of course now he has since passed. impressive guy from what i[ve read in the last 30 minutes. she also says she saw the knife in an antiques book and that's where it talked about the green jigged bone handle being the most rare. not sure of the title of the book now.

[iDroolT]

any of you master knife mechanics near oklahoma or colorado? i'd like someone knowledgeable to have a look in person. i don't mind a little road trip for a good reason!

also, none of you have to worry, no one is going to tinker on this thing unless they're a professional. i wouldn't dare. she's taken very good care of the knife just by having it wrapped up all these years. hasn't left her side in 20 years and been in possession for at least 30. she's been a good caretaker.

[Bill DeShivs]

I do know there were some parts that were probably sold by Jim Parker when he bought and decimated Case.

[iDroolT]

I do know there were some parts that were probably sold by Jim Parker when he bought and decimated Case.

interesting. i wish i knew the history you're referring to. i didn't know the company went through such a downturn and sold. i'll have to do some learning tonight.

what are your thoughts on the missing model number stamping?

i encourage you all to voice your honest opinions about the knife good or bad. i've always liked knives myself, but i was never into it enough to be educated on the subject. i had a friend that had a nice collection that filled a trunk at one time and we looked through some things he had a few times. always was interested, i just never spent any money on it. actually made a few with him that i still have, still my opinion as an amateur has no weight.

i'm amazed how little wear the blade has from sharpening other than the scratches from bad technique if it is indeed the original. some of the heavily used old knives have half a blade left. is it possible it's unstamped prototype with a steel pin? why would someone pin it with steel if they were tampering with it or repairing it and not replace it with nicklesilver? why would they use steel if they were trying to create a forgery? that just makes no sense because if you're trying to fool someone you don't create a situation where it draws their attention to "tampering". i lean on the side of extremely odd but authentic. none of it makes sense.

does removing the nickel pin destroy it? maybe it worked its way out and was lost over years of use although it was never sharpened? lost the pin, replaced it with a nail just the right size.

[BestVintageKnives]

The one below appears to have jigged bone handles.

You can always contact Case and see what they say. I'd be surprised if they provided any information, but it's always possible. They have a phone number on their contact page- https://www.caseknives.com/pages/contact-us


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The pivot pin look darkened as well. Just like the OPs knife. Killgar seems to have proven this knife is original and not made from parts or a faked stamp. Nice job Killgar.