What's the difference between a "jackknife" and a "peanut"?

and small.

The Case Peanut is the only knife I know about that made it to the Moon.
 
I believe a "peanut" pattern can refer to any slip joint that is 3 inches or less closed. If the blades open from one end, it's a jack knife that may be sized like a peanut. The slip joint pattern terminology is confusing to me.
 
marcinek said:
A peanut is a specific pattern of jack knife.
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marcinek nailed it.

A peanut is a small serpentine jack. But the peanut name is given to a small serpentine jack that has a distinctive direction to the serpentine curves, with a distinctive downturn to the front bolsters towards the back springs of the knife. Thjere are similar serpentine small jacks, but without the distinctive turn to the front bolsters, they are more of a dogleg jack.

A Case peanut with white delrin scales. Note shape and direction of front bolsters.
28982240112_e9a7d53ca9_c.jpg
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demoncase said:
What's the difference between a beer and a lager?

The former's the generic catch-all term, the latter's the specific style.
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Actually jackknife is not a generic catchall for slipjoints...a slipjoint can be a jack knife or a pen knife.
 
jackknife said:
marcinek nailed it.

A peanut is a small serpentine jack. But the peanut name is given to a small serpentine jack that has a distinctive direction to the serpentine curves, with a distinctive downturn to the front bolsters towards the back springs of the knife. Thjere are similar serpentine small jacks, but without the distinctive turn to the front bolsters, they are more of a dogleg jack.

A Case peanut with white delrin scales. Note shape and direction of front bolsters.
28982240112_e9a7d53ca9_c.jpg
[/url][/IMG]
Click to expand...

And then jackknife really nailed it.
 
jackknife said:
marcinek nailed it.

A peanut is a small serpentine jack. But the peanut name is given to a small serpentine jack that has a distinctive direction to the serpentine curves, with a distinctive downturn to the front bolsters towards the back springs of the knife. Thjere are similar serpentine small jacks, but without the distinctive turn to the front bolsters, they are more of a dogleg jack.

A Case peanut with white delrin scales. Note shape and direction of front bolsters.
28982240112_e9a7d53ca9_c.jpg
[/url][/IMG]
Click to expand...
Thank you, sir - your explanation was exactly what I was looking for. Much appreciated.
 
My understanding is that a jack knife is a slip joint that has a large main blade and a smaller secondary blade, both on the same end. Usually, but not always, the secondary blade is a pen blade, as is the case with the Case Peanut. But, a harness jack will have an awl as a the secondary blade and a cap lifter jack will have a, well, a cap lifter secondary. Arguably, the Barlow is the quintessential jack knife.

Pen blades and pen knives should not be confused. As noted above, a pen knife is a 2 blade slip joint with the main blade and smaller secondary blade on opposite ends and typically the secondary blade on a pen knife is a pen blade.

Lastly, when both blades are the same length and on the same end, I'm not sure what they are called. Muskrats, Trappers and Electrician (TL-29) knives have 2 blades on the same end but as far as I can tell, are not typically called jack knives as both blades are the same size.
 
I believe Trappers are jack knives (blades on same end). The muskrat has blades that open from each end usually.

The Peanut is actually a very specific knife design/pattern and not just closed length. It was shaped like a "peanut". But many people will refer to one or two bladed knives that are 3 inches or less as peanuts. As you said, pen knives are not to be confused. But I stay confused most of the time personally.

Serpentine is another term that confuses me relative to slip joints.
 
pinnah said:
My understanding is that a jack knife is a slip joint that has a large main blade and a smaller secondary blade, both on the same end. Usually, but not always, the secondary blade is a pen blade, as is the case with the Case Peanut. But, a harness jack will have an awl as a the secondary blade and a cap lifter jack will have a, well, a cap lifter secondary. Arguably, the Barlow is the quintessential jack knife.

Pen blades and pen knives should not be confused. As noted above, a pen knife is a 2 blade slip joint with the main blade and smaller secondary blade on opposite ends and typically the secondary blade on a pen knife is a pen blade.

Lastly, when both blades are the same length and on the same end, I'm not sure what they are called. Muskrats, Trappers and Electrician (TL-29) knives have 2 blades on the same end but as far as I can tell, are not typically called jack knives as both blades are the same size.
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There are dozens upon dozens or patterns of both pen knives and jack knives, with any number, type, and arrangement of blades and springs. Again, check out Levine's Guide.

And one could argue that any one of many patterns is the quintessential jack knife. Not sure what makes a Barlow more special than any other pattern.
 
22-rimfire said:
I believe Trappers are jack knives (blades on same end). The muskrat has blades that open from each end usually.

The Peanut is actually a very specific knife design/pattern and not just closed length. It was shaped like a "peanut". But many people will refer to one or two bladed knives that are 3 inches or less as peanuts. As you said, pen knives are not to be confused. But I stay confused most of the time personally.

Serpentine is another term that confuses me relative to slip joints.
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Levine's Guide. :)
 
marcinek said:
There are dozens upon dozens or patterns of both pen knives and jack knives, with any number, type, and arrangement of blades and springs. Again, check out Levine's Guide.

And one could argue that any one of many patterns is the quintessential jack knife. Not sure what makes a Barlow more special than any other pattern.
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Don't have access to Levine. Does he make any distinction on blade length for a jack knife. That is, does he consider a Trapper or Electrician a jack knife?

As for the Barlow, I rather suspect that more Barlows have been produced and used (at least here in the US) than any other single jack knife pattern. Just my guess.
 
This is how I have always understood the terms jack knife and pen knife. I would guess some call a Barlow a jack knife because the blades are on the same end. The barlow is my favorite but it is hard to find quality barlows at a decent price nowadays. Sadly, cheap Chinese junk knives in the barlow pattern predominate, and then on the other extreme are some good ones that are high priced.
 
pinnah said:
Don't have access to Levine. Does he make any distinction on blade length for a jack knife. That is, does he consider a Trapper or Electrician a jack knife?

As for the Barlow, I rather suspect that more Barlows have been produced and used (at least here in the US) than any other single jack knife pattern. Just my guess.
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I wish I had it with me at all times! Sadly I don't.

I believe Levine's demarcation between jack knife and pan knife is one of size, where he has Trappers, Muskrats, and Canoes in with the jacks.

Maybe someone has got it handy!
 
I guess it should be noted that in common (non-knife people) usage, "jackknife" is often used interchangeably with "slip joint". So, a SAK camper would be often called a jackknife.

I can't find the etymology link right now but one word history article I read linked the term "jackknife" to the older term "jack leg", which was a term of derision for inexpensive or shoddy work. A "jack leg lawyer" was a lousy lawyer and a "jack leg workman" was somebody who did shoddy work. In this word history theory, "jackknife" is short for "jack leg knife" which would be a cheap, shoddy knife. And if you think about it, that is a perfect way to think about some of the crap folding knives made in yesteryear, like say, the Russel and imported Sheffield Barlows that were crudely mass produced and a very far cry from a "Tom's Choice" Barlow from GEC.

One only need to read old Boy Scout and other camping literature from the 30s through 50s to see the term "jackknife" used in this way, often referring to things like the crudely produced Ulster BSA knives (among others).

I would love to hear what people find in Levine. But I thought the more tightly defined use of the term meant 2 blades, same end and small secondary.

But just to confuse things... Here is a link to a 1926 Schrade catalog.
Notice that they have jack knives that have blades on both ends. If we want consistency, we should do mathematics, not knife collecting.

http://www.collectors-of-schrades-r.us/Catalogs/images/1926_Schrade_Catalogs.pdf
 
There is a move in diving called the Jackknife, where the diver, keeping his legs straight in the air, touches his toes. The body's shape actually has more resemblance to a 2-blade penknife with both blades partially opened. I even once saw that portrayed in an old cartoon, where the image of the diver was briefly replaced with an image of a 2-bladed pocketknife with the blades opening from opposite ends.

I do believe that many people referred to any type of old-style pocketknife as a "jackknife". I've also heard some people from the UK refer to any folding knife as a 'penknife', even something like a SAK Swisschamp.

Technically, I would class a Buck 110 or a sodbuster, as well as any of the single-bladed modern one-hand folders as jackknives.

I do have an older edition of Levine's book that talks about the differences among jackknives, penknives, and multi-blades. I think I remember something he said about some jackknives having blades that open from both ends. Possibly like a muskrat?

Jim
 
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