Thread: Kydex Sheaths - also a kydex vs leather discussion

So being a knife maker, or a guy who makes knives involves a little more the just taking a lump of metal and making it sharp, you need to choose the steel, shape the steel, heat treat the steel to your desired requirements, sharpen the steel then become a handle maker as a knife without a handle is not very useful, and believe me there is a whole lot involved in handle material and design, then once all that is done you need something to carry the knife in, usually this is a leather sheath so you also need to become a leather worker, but recently I have been wondering about kydex and so decided to investigate and have a go.

Kydex is a trade name for a line of thermoplastics of acrylic-polyvinyl chloride chemistry, manufactured in America, which is why it is difficult and expensive to get in New Zealand, a bit like mustangs and cheerleaders.

Joking aside it is a type of plastic that is easily folded when heated to about 175C and will maintain its shape when cooled down, unlike a sponge it has no memory and will accept and hold its new shape.

It has advantages as a sheath material in that it is waterproof, salt water proof, blood proof, sweat proof, soap proof, petrol proof, concentrated sulphuric acid proof...well its pretty damn resilient, and if you get it dirty you can just rinse it off with water, no staininging; it is also hard having a Rockwell hardness in the nineties, as a comparison my knifes come out at 59, and yes higher is tougher.

It is also lightweight, I use stuff which is 2mm thick and its lighter than 2mm thick leather and definitely stronger, it comes in may different colours:black, green, orange, pink, red, purple, brown, blue and also patterned like carbon fibre and multi patterned like digi camouflage, urban camo...well there are lots of options out there, the single colours are cheaper, once you go for the papered stuff you pay three times the basic price, but it does look pretty cool.

Its held together by metal eyelets, not stitched like a leather sheath, this gives you options running paracord through it to act as a belt loop, or you can use a tec-loc or you can use more kydex, or webbing or leather to make a belt loop which you attach with post and screws.

It does not look as nice as leather does, nor does it feel quite as nice, it does not look or feel horrible though and the fact that if it gets wet it will not lose its rigidity and the knife won't slice straight through the leather into your hip when you go to resheath it more than makes up for the difference in looks I feel.

Its form fitted so does not need a straps or covers to retain the knife, this does mean it will make some noise when you draw or replace the knife in its sheath, but unless you are sneaking up to deer, pulling a knife and leaping on them and stabbing them to death I do not see that as being a problem. . Kydex never stretches, does not scratch easily and wears in rather than wears out.

You do need some specialised equipment to make a sheath, just like leatherwork, but you could always just grab a hammer and have a bash.

Heres the first one I made:
testing size


in the press


out of the press


marking holes for eyelets

placing eyelets


roughed to shape


added tec-loc, note drain hole


other side, note contoured thumb ramp


As I did it I learnt quite a bit, having a knife belt sander with an old 50 grit belt and a knife polisher helped, as did a drill press and the dies to flare the eyelets, the tec-loc was one I had lying around, as was the knife. All in all i am very happy with it and I know the next one I build will be better...

So I will be making these available for my future knives, some knives will have leather sheaths, some kydex and some will be your choice, you tell me when you order a knife.

Also I am prepared to make kydex sheaths for sale, they are a custom fit item so I need your knife to make it.
Cost for a simple kydex sheath, with up to 10 eyelets (five per side), paracord wrap, and a blade length of around six inches in a single colour would be about $60, including shipping in NZ.

If you want a tec-loc (which are fantastic) then you can either supply me one or I buy them for $25, so you would need to add that.
The special coloured camo kydex costs me three times the cost of the black stuff, so a simple sheath with just eyelets and paracord will be around $120.

I am more than happy to make kydex sheaths (and knives too), turnaround will be fast, as long as its a colour I have in stock, otherwise I need to get it in, but to do so I do need your knife, which will be returned with the original and new sheath, I am also happy to give your knife a sharpen as well at the same time, if wanted.

Feel free contact me.
Shelley

This is brilliant work and I would be so keen for you to make me a sheath is you still do them

Suspect the 94 rockwell is a HRB rating (94 HRB is 16 HRC), otherwise you could not grind or file it, as it will be infinitely harder that your abrasive materials.

How are you heating the Kydex before putting it in the press?

Really good to know how to clean kydex sheaths, have one myself and it's tricky to wash.

Originally Posted by quentin

Suspect the 94 rockwell is a HRB rating (94 HRB is 16 HRC), otherwise you could not grind or file it, as it will be infinitely harder that your abrasive materials.

Actually Rockwell R rather than Rockwell B. Definitely a totally different scale than HRC. Also the statement that higher hardness = tougher is a bit questionable.

But we are discussing and correcting a 7.5yr old post!

I guess this is a bit like the wood blued plastic stock discussion the kydex is modern and does the job but the leather ahh workmanship design just better

Rockwell R scale, closer to 90, gun barrels are 26-40, remember how Rockwell works, it’s a deformation test, a hacksaw will still rip it to shreds as you are cutting not pressing.

Originally Posted by Shelley

Rockwell R scale, closer to 90, gun barrels are 26-40, remember how Rockwell works, it’s a deformation test, a hacksaw will still rip it to shreds as you are cutting not pressing.

Yep, gun barrels are 26-40ish Rockwell C. Kydex is around 90 Rockwell R. The two scales are not comparable and not commonly converted between. Kydex is fairly hard for a thermoplastic, and much softer than hardened steel (including hacksaw teeth).

Is there a way to run the sheath outline closer to the blade? More, smaller eyelets for instance?

You can do a folded sheath, then you only have the eyelets on one side, if the eyelets are too close to the blade there is not enough space for the blade to slide in and out, I suppose you could make a standoff, then run the eyelets right next to the blade.

@Shelley What is your current cost on these for a single colour?

Depends on the size of the knife, the retention system and weather it’s taco or pancake, and finally the colour, stand colour cost me about 60 a sheet, anything like camouflage cost me about 120-would not recommend camouflage anyway put it down and you lose it.