Can Repeated Heat-Molding of Kydex Damage the Heat Treatment of a Knife?

[billygoat162]

This may seem like a silly question since plenty of people use their knives to mold Kydex sheaths, but it seems like most sources recommend getting it to about 300 F, and some recommend going even hotter to get a perfect fit. I read that some people temper 1095 as low as 325 F, and this seems awful close to the temperature for molding Kydex (lower than what one source recommended). My main concern is using the same knife for multiple sheaths over and over again. I've never worked with Kydex, but if I start, I know it's something I will want to do a lot of. Has anyone ever heard of or had problems with edge retention after repeated molding? Does anyone use/make prop knives, like the prop guns that are sold for molding Kydex sheaths?

 

[luke213]

I haven't seen that but typically with Kydex your heating the Kydex then putting the knife in place to press. So the heat is in the Kydex some will transfer to the knife but I suspect the mass of the knife is enough to work like a large heatsink and the temp would be low enough not to matter. If you were really concerned you could probably drop the temp of the knife before molding Ie put it in the fridge or something then heat the Kydex and press. This would lower the temp transfer to the knife. I wouldn't get it Super cold but 40 degrees wouldn't likely hurt anything. It will likely shorten your working time till the Kydex starts to set up though going that route.

Luke

 

[David Brown]

In my experience, no it will not hurt the knife at all.
Some coatings on the other hand maybe.