A Brief Study On Swedges

KnifeHead

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Someone asked a while back, "What is a swedge and what are they used for?" My mentor Tony Bose and I sat down and he explained what was going on with the swedges on the knife in the following images. (Thanks Tony!)

Swedges have 4 basic purposes:

1. They improve the eye appeal of a blade.

2. They make the blade thinner at the spine and therefore improve it's ability to cut.


Specific to slip joint folding knives they:
3. Make room for the blades to pass each other when opening and closing.

4. Provide access to nail pulls


This 3 blade premium stockman has some good examples of swedge work. From the top you can see that there isn't a lot of extra room for blades. The swedges on each blade play a part in making this knife work well. Imagine what this knife would look like without swedges. Eye appeal is definitely at work here in the lines on these blades.

swedges2.jpg

swedges3.jpg


There wasn't much worry about blades rubbing on the old knives because they were USED! In today's collector market, blade rubs are a no-no so care is taken to make sure there is plenty of room for the blades to pass. But, you don't want a knife that is too wide so swedges will enable the maker to keep the knife as narrow as possible.

Now take a look at the position of the blades in the image below.

swedges1.jpg


The master clip blade has symmetrical cut swedges. It has it's own spring and therefore it's own pocket to house in, but still the sheep's foot blade is very close. The drawn swedge of the sheep's foot and the cut swedge of the clip blade allow plenty of clearance.

The spey and sheep's foot blades share a spring. Special attention has to be paid to make these two blades play nicely together. A cut center liner(not a full profile liner) is used and the sheep's foot blade is crinked(bent) toward the center. You can see in the image above that the tip of the sheep's foot blade is about centered over the center liner. Crinking one blade doesn't provide enough clearance between blades so cut swedges are employed between the spey and sheep's foot blade.

There are 2 types of swedges: cut swedge and drawn swedge

The cut swedge plunges in where it begins on the spine and tapers out towards the tip. A correct swedge will end before it gets to the tip of the blade. Otherwise, blade sharpening over time could potentially involve the swedge resulting in an ugly blade.

swedges6.jpg


The drawn swedge tapers gradually from where it begins on the spine and tapers out again toward the tip.

swedges4.jpg


swedges5.jpg
 

VCM3

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Kerry,what a great informative thread.Very nicely done !
That knife is really outrageous.The blades are spectacular!
-Vince
 

T.A.DAVISON

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Nice job there Kerry, I think the swedge is here to stay. :D


T.A.Davison
 
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Kerry, thank you for taking time to post that it was really informative. That is one heck of a nice knife too! Joe
 

KnifeHead

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Ya'll R welcome as always. BTW, I also posted some pics of that knife in the Bose sticky.
 

Mike Robuck

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That was a well-written write up along with the usual great pictures, Kerry.

So a double-swedge on some of those old single blades you've posted in the past of Tony's are just for looks then? I think one was a Challenge knife?
 

JatMat

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Kerry,

Thanks for the lesson, great pictures also.

James
 
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That was a well-written write up along with the usual great pictures, Kerry.

So a double-swedge on some of those old single blades you've posted in the past of Tony's are just for looks then? I think one was a Challenge knife?

Mike, double swedges on a single blade makes the back of the blade thinner so it will go through something easier. You may want to cut stuff with it.
 

KnifeHead

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That was a well-written write up along with the usual great pictures, Kerry.

So a double-swedge on some of those old single blades you've posted in the past of Tony's are just for looks then? I think one was a Challenge knife?

Thanks for the kudos.:)

(Tony beat me to the answer to your question :p )
 
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Mike, double swedges on a single blade makes the back of the blade thinner so it will go through something easier. You may want to cut stuff with it.

Classic example of form following function.

My backpocket does cut stuff--
and, in my opinion, the double swedge also adds to the aesthetics.
 

Mike Robuck

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I knew that about the swedge on the front of a clip point. Guess I never thought about it working near the end of the blade as well. :eek:
 
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Great information and pictures Kerry. Thank you for posting. I really like the Case bone on that knife.:thumbup::thumbup:
 

Blues

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Great thread. Well done!
 

jd_elam

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Great information and pictures! Thanks for sharing the information.
 

canineforge

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Enjoyed this information! The swedge can definitely add sex appeal to the overall looks, and the functional reasons all make sense.
Hope you keep up the studies, Kerry! How about one in the future on nail pulls?

Thanks, Joe
 
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