Resiprene C and Kydex

Joined
Feb 6, 2012
Messages
436
I just got a kydex sheath for my new 511. Fits perfect, but its very tight. It seems maybe the Resiprene C handle is sticking a bit to the kydex when i insert or remove the knife. Is there a way to break this in? I tried a little gun oil inside the kydex where the handle locks in and its helped a lot, but that seems like a temporary fix.
 

leatherman

leathermoderator
Moderator
Knifemaker / Craftsman / Service Provider
Joined
Nov 30, 2001
Messages
13,536
Res-C and kydex and leather in a pouch type configuration has been a problem from day one. If the retention relies on the handle, then it will be very "sticky"

There is a very fine line with this formula, some of us sheath makers have been able to work with it, but most of us are still fighting it.

If the sheath doesn't fit well at first, it probably wont fit well ever. Best advice is to send said sheath back to the maker for alterations or to get a new sheath with a little less retention. Kydex will not break in, its one of the nice things about it, and one of the frustrating things about it at the same time. :) I am fascinated by the stuff.
 

azwelke

azwelke.com
Knifemaker / Craftsman / Service Provider
Joined
Nov 12, 2007
Messages
4,029
No offense to Leatherman...but kydex will break in and loosen with use. Quite a bit too, with heavy use. But there is a point when too tight is just too tight. Kydex probably will not loosen enough for "that" to become comfortable.

Kydex sheaths that start out loose, will become too loose over time and with hard use. IMO.
And everybody has different hand strength... especially the difference between the young and the old folks.

Also some knives of the same make and model can vary in thickness, causing kydex sheaths to be too tight or too loose.

If you got it from me, I would be happy to loosen it for you.


Al
 
Last edited:

leatherman

leathermoderator
Moderator
Knifemaker / Craftsman / Service Provider
Joined
Nov 30, 2001
Messages
13,536
How long does it take!? I have an original to the knife SHe sheath that still has its very strong retention. A River City kydex sheath for my Polkowski Companion still wants to drag my pants into a wedgy. Both over ten years old.

fyi, I like that aspect about kydex, I dont want it to loosen.
 

azwelke

azwelke.com
Knifemaker / Craftsman / Service Provider
Joined
Nov 12, 2007
Messages
4,029
Kydex should loosen up if you use and carry it for a week or 2:).....If it doesn't, it's too tight and probably will not loosen "that" much. There is a point where the kydex can be too tight and does need to be loosened.

I EDC a Boss Jack, and after a month of use, and being next to body heat, the kydex has loosened a lot. If I had made the sheath looser to begin with, it would be too loose after 1 month of carry.
I have another BJ sheath that I EDC'd a couple months longer and it is even looser.

Al


How long does it take!? I have an original to the knife SHe sheath that still has its very strong retention. A River City kydex sheath for my Polkowski Companion still wants to drag my pants into a wedgy. Both over ten years old.

fyi, I like that aspect about kydex, I dont want it to loosen.
 

leatherman

leathermoderator
Moderator
Knifemaker / Craftsman / Service Provider
Joined
Nov 30, 2001
Messages
13,536
Good to know. :)

How do you counteract the grippyness of Res C? Every sheath I have, leather and kydex, seems to hold on to that stuff like velcro, it feels like pulling a cork out of a wine bottle.
 
Joined
Dec 23, 2006
Messages
1,375
most of my coated blades have abraided the inside until it fits just right. It happened a lot faster in the cold when the kydex was tighter and less plastic. My ruck sheath was firm in the warm at first, but took 60+ lbs of force to drawn(comparable to 70# compound bow) at first in the cold, now its like 10-15 warm or cold, just perfect. I guess it could be fairly different with hand shaped scales and kydex with no retention on the blade.
 
Joined
Dec 23, 2006
Messages
1,375
in my res-c kydex, I like it when the kydex is really tight around the top of the handle or holds below the guard, and flared out so it doesn't cut the handle. A miniscule breakin makes a HUGE difference in the draw force required.

Just like pistols, tight fits will break in just right, loose ones only get looser.
 

tundratrader

BANNED
Joined
Jan 10, 2009
Messages
1,312
It takes forever for a kydex sheath to get broken in. I think the break in is plastic being removed little by little out of the sheath. On my res-c I put a dab of oil of whatever kind I am using on the blade for protection right around the top choil/ricasso area of the knife. Makes it easy to come in and out for about half a dozen times.
 

leatherman

leathermoderator
Moderator
Knifemaker / Craftsman / Service Provider
Joined
Nov 30, 2001
Messages
13,536
I've double waxed the inside of my sheaths in an attempt to make the Res C less tacky to it, but it still wants to grab but is much less so.

I'll be trying the oil idea for my kydex though, sounds like a good idea.
 

David Brown

Kydex Sheath and Holster Artist :)
Moderator
Knifemaker / Craftsman / Service Provider
Joined
Jun 4, 2001
Messages
12,750
Hmm, I have sheaths and holsters that I have made 10 years old too and they have not loosened up ? body heat, Arizona heat or otherwise ? Now if you leave it on your dash when it is 115 in the summer it will deform.

In my experience, kydex does not break in, what can happen is the coating gets worn off thus making the sheath looser.

a lubricant will make the rubber a bit looser at least on kydex it will.

Leather I do not know ?

If the sheath is made Buy Brown send it back and I will make you one that fits your needs better and pay for your return shipping.
 
Joined
Feb 6, 2012
Messages
436
Thanks for all the replies guys.

Al, it is one of your sheaths. I ordered it and 1 for an ESEE 4 and love them both. I've been playing with the 511 in the sheath all weekend and it does feel a bit better. If i use my thumb to push off on the sheath it works like it should.
 

jdigi101

Gold Member
Joined
Apr 21, 2010
Messages
1,095
I have tried a lot of Kydex with res c combos. BuyBrown has always been great. My first kydex was from Dave for a SR HR gen 2. Very snug and popped right out with a thumb push. My experience has been the same with all his res c handle sheaths.

I did get a new Rainwalker for a Scrapper 5 and would have to say his new kydex is nothing short of amazing.
 

azwelke

azwelke.com
Knifemaker / Craftsman / Service Provider
Joined
Nov 12, 2007
Messages
4,029
blt 2 drg, Thank You:) if it ever doesn't make you happy, please send it back, and I will take care of you.

Thank You
Al




Yes, I believe this. In my experience kydex will break in. I have personally experienced it too:)
Al


in my res-c kydex, I like it when the kydex is really tight around the top of the handle or holds below the guard, and flared out so it doesn't cut the handle. A miniscule breakin makes a HUGE difference in the draw force required.

Just like pistols, tight fits will break in just right, loose ones only get looser.
 
Last edited:

leatherman

leathermoderator
Moderator
Knifemaker / Craftsman / Service Provider
Joined
Nov 30, 2001
Messages
13,536
anyhow, its a consensus that Res C and just about any sheath material is the pain in the neck. Anyone that has a way of making one that works well with the stuff has my respect. :)

Mr Brown has earned mine through ten years of working alongside him.
 

Kiah

S&S Moderator
Moderator
Knifemaker / Craftsman / Service Provider
Joined
Jul 20, 2006
Messages
17,579
In my experience the form of Kydex doesn't break in, though there are things that will cause the fit to change. Sharp angles from the knife itself can abrade the hold points, rubber handles can abrade or slightly compress over time, or the top eyelets can loosen a bit if there is enough lateral pressure on the draw. As for Res-C, a wide mouth and putting the retention more on eyelet placement than handle coverage seems to be the best way I've found to deal with it.
 
Joined
Dec 6, 2011
Messages
1,301
Fisrt of all I admit I know NOTHING about forming Kydex (never done it) . However I gather it comes as a sheet , is heated to a certain temp to make it plyable and then formed , right ? So couldn't the tight end of a sheath be held in say a pot of heated water for a shot time and then simply opened just slightly to lessen the grip on the Res-c handle part ? If I'm completely wrong , someone please take a moment to explain why this is not possible .


.........................................
HOLD MY BEER AND WATCH THIS !
 

azwelke

azwelke.com
Knifemaker / Craftsman / Service Provider
Joined
Nov 12, 2007
Messages
4,029
IMO when kydex is formed to a knife, it holds the knife in the seated position. When you draw the knife out, the kydex will spread alittle and spring back into place. after inserting and removing the knife, the kydex is forced to be in an un natural position (since naturally it sits in the closed seated position). That action will loosen kydex. (if you sheath and un sheath the knife once or twice a day, it will probably never loosen. You have be using it a lot, or just playing with it a lot:))

You can take a piece of kydex that is bent into the folded over position and completely closed. Then spread it a little ( alot of times) you will see it will not stay closed, therefor it has loosened or spread. Kydex has a memory of a sort and remembers its last position, thats how it works. When its last position was a little spread open (while drawing), and now the knife is re inserted ( it's in it's closed position). The sheath starts to remember a happy medium between open and closed. That is when you will feel it loosen.
Also bending the kydex back and forth creates heat. It has to, because you are forcing the electrons to move when bending back and forth, thus creating heat. It's micrscopic but I am sure the kydex knows about it:)
Also aggressive handles will wear a path making the sheath even looser, and feeling even more broke in.
But there is a point, where the kydex will not "loosen" or "break in" any more. It's a fine line, but it's there.

Al
 

azwelke

azwelke.com
Knifemaker / Craftsman / Service Provider
Joined
Nov 12, 2007
Messages
4,029
A little pulsating heat to the tight spot will usually take care of it. Hot water may work, you want to bring the heat on slow and check often.
Al


Fisrt of all I admit I know NOTHING about forming Kydex (never done it) . However I gather it comes as a sheet , is heated to a certain temp to make it plyable and then formed , right ? So couldn't the tight end of a sheath be held in say a pot of heated water for a shot time and then simply opened just slightly to lessen the grip on the Res-c handle part ? If I'm completely wrong , someone please take a moment to explain why this is not possible .


.........................................
HOLD MY BEER AND WATCH THIS !
 
Joined
Jul 28, 2006
Messages
1,077
I would agree with Kiah.
In my experience Kydex doesn't "break in" it may wear in a few spots allowing the knife to be drawn out easier.
All Res-C or rubber type handles should get a wider opening to allow the handle to be in the sheath with out tearing them up. And of course proper eyelet placement is key.
 
Top