Reducing Knife Blade Length

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foxtrot

Member
Jan 18, 2009
27
0
chesterfield
I have a Swiss Army knife with a blade that obviously exceeds the legal carry limit. How should I go about reducing the blade's length without damaging the rest of the blade? Advice appreciated.
 

Stew

Bushcrafter through and through
Nov 29, 2003
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stewartjlight-knives.com
First off, what model - does it have a lock that needs removing too? I can't recall ones that are longer than 3" that don't have a lock but may have missed one.

Second, to trim it down, do you have a belt grinder? Basically grind a bit, dip in water, repeat. Don't let it get too hot or it'll lose it's hardness. If you don't have a belt grinder, what other tools do you have access to?
 

Laurentius

Bushcrafter (boy, I've got a lot to say!)
Aug 13, 2009
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First off, what model - does it have a lock that needs removing too? I can't recall ones that are longer than 3" that don't have a lock but may have missed one.

Second, to trim it down, do you have a belt grinder? Basically grind a bit, dip in water, repeat. Don't let it get too hot or it'll lose it's hardness. If you don't have a belt grinder, what other tools do you have access to?

Likewise I am not aware of any SAK in that category, I own one which is both lockable and has a blade over 3 inches, it would be rather pointless altering either features as I only ever take it out when I have a legitimate reason too in which case neither of those features matter. Easier by far simply to get an EDC legal model and keep the other one for those times when it is legit to carry.
 

hughtrimble

Full Member
Jan 23, 2012
458
78
UK/France
Also note that it's the cutting edge that's of relevance, not the blade length. So long as the cutting edge is three inches or under, you're good. Ignore the .gov page about it, read the actual legislation.
 

Robson Valley

Full Member
Nov 24, 2014
9,959
2,664
McBride, BC
You can do the reshaping, if you have to, with a Dremel and some cutoff wheels.
Just don't lean into it and cook the steel.

My SAK 'Prince' is my EDC and it has a biggest folder blade of 2.4 inches (60mm)
I'm not quite stupid enough to do things so that the blade folds on my fingers.
 

C_Claycomb

Moderator staff
Mod
Oct 6, 2003
7,354
2,365
Bedfordshire
I too am unaware of any SAK with an over long blade that isn't a lockable design.

I shortened a standard SAK with the intent of making it flight carry-on legal, and had it confiscated because airport security measure blades "to the fulcrum"...meaning they measure from the point all the way to the pivot pin buried in the handle. :censored::banghead:.

In that case, just shortening it to 6cm measured from the front of the handle made it almost un-usable since the nail nick that allows it to open partially falls in the region that has to be ground away. I had half a nail nick left, and had to do some sharp corner removal with a triangular slip stone.

This week I shortened two blades of a friend's high end (£150 ish) double blade slip joint since they were manufactured at 3.125" long. Used a 120grit sanding belt against rubber contact wheel on my belt grinder. Follwed with 220 for re-setting the cutting edge, and 1200 for cleaning up and sharpening, followed by fine emery paper and polish. Without the grinder I might have used a bench grinder or dremel and manual stones, but watching out for over heating becomes more of a problem.
 

shibafu

Member
Jul 31, 2013
18
8
UK
Also note that it's the cutting edge that's of relevance, not the blade length. So long as the cutting edge is three inches or under, you're good. Ignore the .gov page about it, read the actual legislation.

As far as I know this hasn't been tested in court, and while that might seem to be the common-sense interpretation of the phrasing in the legislation, there's no guarantee that a judge would interpret it that way. As we know, the courts have applied some unexpected mental gymnastics to this legislation in the past (Harris v DPP). A belt-and-braces approach of choosing a blade that's under 3" by any sensible measure is not unreasonable. Based on a handle-to-tip measure, the nylon-handled 108mm models are slightly over 3" I think.
 

foxtrot

Member
Jan 18, 2009
27
0
chesterfield
Thanks for all your advice. Am unable to say which model it is but I have had it for a long time and would rather use it than replace it, especially with all the accesories it has. It does have a locking mechanism but this has been rendered inoperable by a hefty dose of Araldite. I can borrow a belt sander easlly enough so will be going down that route.
 

Shelley

Forager
May 27, 2015
140
1
New Zealand
A very light touch with an angle grinder and some judicious work with a file will also do the job, by sander I think people are referring to a 2 x 72 sander, which are fairly rare.
 

Shelley

Forager
May 27, 2015
140
1
New Zealand
No, belt sanders are pretty common and can be any size. You can pick them up in Aldi for £25/£30 sometimes.

Wow, you are lucky then, I could not find one at all in my country, as in no one sells them or imports them, in the end I had to build one totally by hand, the belts I can get made up as custom orders, but even then they kept asking if I was sure I wanted 2 x 72...oh and I had to buy a minimum of 10 before they would make them.
 

Keith_Beef

Native
Sep 9, 2003
1,366
268
55
Yvelines, north-west of Paris, France.
They are available in NZ, and seem to be only slightly more expensive than here in Europe.

At this page, you can see a Kity/Scheppach model almost identical to one that I picked up when it was on special offer for about €100 in Castorama (French B&Q). French Amazon has them for about €180 to €200 at the moment, but you can find them for less.
 

Robson Valley

Full Member
Nov 24, 2014
9,959
2,664
McBride, BC
I have changed the blade profiles of about a dozen farrier's hoof knives to make them into better shapes for wood carving.
I use a Dremel and Dremel cutoff disks. Just take your time, little by little, so you don't cook it. Only have to do it once, right?
After market disks are thin, they wear fast and you really spend more, to get the same job done = crap.
1. Hearing protection.
2. Full face protection. A cutoff that explodes at 15,000 rpm really stings, every time.
3. Some sort of dust collection.

That profile can be smoothed out with the same Dremel and a stone.
Plus, the Dremel has many uses, unlike a stationary belt sander, as useful as they are.
 

Shelley

Forager
May 27, 2015
140
1
New Zealand
They are available in NZ, and seem to be only slightly more expensive than here in Europe.

At this page, you can see a Kity/Scheppach model almost identical to one that I picked up when it was on special offer for about €100 in Castorama (French B&Q). French Amazon has them for about €180 to €200 at the moment, but you can find them for less.


Nah, no 2x72, those short fat belts heat up too fast, need long thin belts so that they stay as cool as possible.
 

Stew

Bushcrafter through and through
Nov 29, 2003
6,446
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Aylesbury
stewartjlight-knives.com
Nah, no 2x72, those short fat belts heat up too fast, need long thin belts so that they stay as cool as possible.

It depends on what you really need. Most folk don't need a 72" belt - I have a shorter linisher as well as a 72" one and it's never been a problem with the knive I've made. People can get bogged down in having the right gear. Plenty of folk make knives with short belt sanders (assuming that's the angle you're coming from). Also, if you're only using one occasionally, getting a big sander isn't necessarily necessary.
 

brancho

Bushcrafter (boy, I've got a lot to say!)
Feb 20, 2007
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Whitehaven Cumbria
Why? If he wants to play about, what's the harm to anyone else?
Stew I am all for modding a knife to improve functionality or looks. To me this is making a mess of what was probably a perfectly good knife that could be used perfectly well in the right circumstances.
Glueing a lock shut and shortening a blade is not elegant solution but a botch IMO.


Sent from my SM-T580 using Tapatalk
 
Last edited:

MrEd

Life Member
Feb 18, 2010
2,148
1,053
Surrey/Sussex
www.thetimechamber.co.uk
Stew I am all or modding a knife to improve functionality or looks. To me this is making a mess of what was probably a perfectly good knife that could be used perfectly well in the right circumstances.
Glueing a lock shut and shortening a blade is not elegant solution but a botch IMO.


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I would argue thst that it’s his knife and can do with it as he pleases.....
 

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