kydex sandwiches and good fit

[redsquid2]

i am beginning to experimenting with kydex. My first attempt ended up in the garbage can. my second attempt was a taco type sheath, and i am happy with it. it makes a nice "snap" sound when you insert the knife. here is a picture of it:

the third attempt is frustrating. it is the sandwich type. i have tweaked it and tweaked it with the heat gun for about an hour. retention is acceptable, but i want it to make the crisp sound, like "snap," when i sheath the knife. so far, no luck. furthermore, you have to insert the knife at just the right angle, otherwise, it won't go in.
here is that one:

Are taco sheaths just easier to get right?

thanks

--squiddy

 

[Justin King]

Practice! Try molding another one and see if it comes out the same. If not, try to figure out why. Chances are you will still be trying to improve on the 10th or 20th sheath you make. Don't expect too much from the first couple.

 

[redsquid2]

Here is a "funny" mistake I made when I was re-forming one of those sheaths. I was using a butane torch lighter, and toasted right through the tung oil finish of the handle. Now the wood is toasted, and I think I will toast the whole thing, rather than try to sand it out.

 

[Justin King]

Are you using a press?

 

[Remyrw]

Part of the problem is the knife shape, the only place it could snap in is only the thickness of the metal and that doesn't give much pop. If it's dragging on the blade itself you'll also have issues getting it to pop in and slide in properly. I use several layers of blue painter's tape on anything the kydex will touch, to make sure I've got a little wiggle room. Every knife is different, and that second one is not going to be easy to get a good pop in fit for in my experience. I've modified my handle designs slightly to make my own sheaths work better..

If you start over, I'd try coming further up the knife with the kydex, so the knife pops in on the protrusion of wood in the finger swell. If the rest of it is not a SNUG fit, just matching the design, it should click in there and hold nicely without interfering with resheathing the blade.

 

[daizee]

Hi Redsquid,

The shape of your second knife is what's giving you fits. Everything tapers towards the tip, so there isn't much to hold onto.
If you try another sheath, but extend the material rearward past the finger bump you'll get retention.
I always over-squeeze and then trim rather than trying to nail the size exactly on the press.

It helps to think about sheath retention before you put pattern to steel, or to plan a divot of some kind in the handle for the kydex to grab. Leather has similar issues

-Daizee

 

[Remyrw]

Yeah, I over size my pieces by a good bit, kydex isn't cheap, but generally I'm not going to get another knife out of a piece by saving that bit of extra so I might as well make life easier. I think we get used to seeing commercial sheaths that click in right at the hilt, but they only do that when the knife is specifically designed to allow that.
Locking THIS is more difficult than

This

 

[howiesatwork]

Squiddy,
I'd suggest removing the rivet under the choil (or ricasso) of the knife, as it closes the sheath too much, and you had to make the kydex fit looser to get the knife to insert. Remove it and tighten the kydex fit and it should work okay. Look at the second picture Remy posted to get the idea.

 

[ERIK KNIVES]

Heat that third sheath up to 275 deg in a BBQ with a good thermometer or a toaster oven. No hotter. 5 minutes with the knife in the sheath. Pull it out and put it in a press and it will snap so much you will most likely want to loosen it up.

 

[redsquid2]

Yeah, I over size my pieces by a good bit, kydex isn't cheap, but generally I'm not going to get another knife out of a piece by saving that bit of extra so I might as well make life easier. I think we get used to seeing commercial sheaths that click in right at the hilt, but they only do that when the knife is specifically designed to allow that.
Locking THIS is more difficult than

I see what you mean, and Wow! those are both very pretty.

 

[redsquid2]

Squiddy,
I'd suggest removing the rivet under the choil (or ricasso) of the knife, as it closes the sheath too much, and you had to make the kydex fit looser to get the knife to insert. Remove it and tighten the kydex fit and it should work okay. Look at the second picture Remy posted to get the idea.

Great idea! I really don't want to use more kydex and make a whole new sheath. THanks.

 

[redsquid2]

Are you using a press?

I used a press, but I put all of the padding on one side, so one side of the sheath came out absolutely flat. Since then, I have taken a heat gun, and reformed that part around the front of the handle. It is much easier to insert the knife now.

I'm still hoping to get that firm "snap", and I have lots of good ideas on how to do it. Thanks.

 

[Remyrw]

Thanks for the compliment, Red. I think that and it's big brother are my favorite designs. Certainly they've been the most popular. Obviously I don't always make them exactly the same way, but the basic outline and concept is the same and I've played with sheaths a fair bit. Visually I prefer the upper one, functionally the lower one is better. Both in the hand and in the sheath. It's a trade off and something to keep in mind when designing a knife, the whole thing has to work together. I had trouble doing that effectively for a good while but as I ran into issues I looked at how other folks were solving them and asked for advice like you did. I've still got a long way to go, but I no longer feel like my kydex is a serious weak point.

 

[cleans up]

Just thought I'd chime in and say thanks. I'm a new user, and just getting back into knives. I've been looking into making a sheath of my own so this is great thread!

Cheers

 

[redsquid2]

Just an update, and thanks again for all the tips.

I kept adjusting the sheath until it had a good tight fit, but then I wanted to make another sheath for that same knife. So I did. It does not look so hot, like some others I have seen, but it has very good retention; maybe too good. Here it is:

 

[cleans up]

looks great, I get the feeling I'll be inspired by this place