Kydex sheet

For us Y60 owners, the dimensions of the top of the case, designed for 360 mm rads with a max thickness of 30mm, limits what can be used there.
I am kicking around some ideas. My present idea as shown in the pictures includes standoffs to extend the top of the case about 35mm or so to allow for a thicker rad or a second set of fans to use a push-pull configuration.
Right now, I bought some Kydex sheet to cut into strips and fit between the top of the case and the raised lid. If anyone has other suggestions, I'm all ears. Thanks!

I posted a kydex axe sheath I was pretty proud of the other day. And made the point that all bushcrafters should learn how to make basic kydex sheaths.
I realize I should at least do a quick guide on how to do that. It doesn't get into advance techniques or tools.
1) What is Kydex?
Kydex is a thermo-plastic. It can be repeatedly heated up. When hot it is very malleable. If a tool is placed between two pieces of hot kydex and pressed on, the cooled kydex will take the shape of the tool until heated up again.
With some basic tools, it allows anyone to create custom sheaths for any tool.
2) What are the pros and cons of kydex?
The biggest pro is it's ability to retain the tool without any additional straps. Kydex is very tough but flexible. When done properly, the kydex sheath opening can actually "shift" out of the way to accept a tool and will only release it if enough force is applied.
It doesn't lose this ability overtime unlike leather.
The next biggest pro is that kydex sheaths are low maintenance and it doesnot degrade over time like leather.
The biggest con is that it holds dirt and moisture close to the blade. This can be mitigated to an extent, but kydex is known to rust and scratch blades. Tools shouldn't be stored long term in kydex. Really nice tools where the finish matters should use a leather sheath.
3) What do I need to start?
While there are many professional tools you can get. To make your first sheath here are a few tools you probably already own:
-Knife (that's being formed)
-Painter's tape
-Oven
-Kydex sheet (0.80 thickness. 12"x 6" (or double the width of your knife plus an inch))
-3/4 plywood. 12''x12''
-Camping Foam 12"x12" (or other dense foam)
-Tin snips
-1/8 Drill bit and drill
-Cordage
-Sandpaper and dust mask
4) What's the process?
-Tape your knife with painters tape. Do 3 layers. This cause the kydex sheath to be a little larger then the knife which will help prevent scratches, corrosion, and fit issue.
-Pre-heat your oven to between 250f and 300f. The hotter the oven is the faster the kydex will get malleable, but also the easier it is to "burn" the kydex. Make sure nearby windows are open.
Kydex doesn't release a whole of fumes, but it still smells.
-Take your knife, lay it on the kydex (smooth side up). Place your knife in the middle and trace the shape of your knife on the kydex. We're making a "taco" sheath where the kydex is folded in half. So make sure there's margins all around.
-Place the kydex in the oven smooth side down. the smooth side is the inside of the sheath. If the oven ends up "burning" the kydex, it still might be salvageable if the smooth side is inside and hides the damage. Check the kydex frequently by picking it up (with tongs or gloved hand) and seeing if droops. Once it starts to droop significantly (it's hard to pick up) its ready to go.
-Take your plywood and foam. Place the plywood on the ground, then a piece of foam. On a easy to reach table, have the other foam and plywood ready.
-When the kydex is ready, take it out with gloved hands, place the smooth side up on the ground foam. Place your knife inside the outline of the knife. Fold the kydex in half, while pushing back against the seam with the knife. This will help seat the knife tightly against the seam and prevent issues.
-Take your extra foam, place it on top. Take the extra plywood place it on top. Stand on the plywood press for at least 10 minutes. Preferably 20 to give the kydex time to cool and set.
You may need someone else to place the foam and plywood for you.
-Pull the sheath out. Remove the knife. Carefully drill a holes along the edge. Avoid drilling into where the knife will sit.
-Carefully mark the excess with a color pencil (the marks can be erased) and cut them away with the tin-snips. This may be difficult. You may have to separate the layers the best you can and cut one at a time.
The most important part is where the kydex meets the handle. This determines the retention. For now leave a "safe" margin of a inch of kydex up the handle. See my pictures for different ideas.
-Sand to remove rough edges. Do this outside and wear a dust mask and old clothes that go immediately into the washer. The dust gets everywhere and is really bad for you.
Stuff the sheath with wads of painters tape to prevent dust from getting into the sheath. Once done, wipe out the sheath with a wet cloth. Don't leave any dust inside the sheath as that may scratch up or even dull your blade.
If you don't want to sand, you can scrape or even whittle the edges with a knife.
-Take the cordage and weave it through the holes in a way that locks the edge together. You don't have to worry about the knife cutting the cordage.
-You're done!
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My first sheath. The p-cord was how I mounted it on my belt.
my second sheath.
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My first axe. There was no retention, but it help protect the edge from damage.
My second axe (once i got quite good at this). By wrapping the kydex all the way around the head, and carefully remvoing kydex on the back of the axe head, I could control how much retention it had.
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Machete sheaths are a lot harder, but this one has served me well. I've fought wildfires with it. Talking climbing up hillsides so steep that it was basically low-incline bouldering.
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A lot of clients have leather sheaths, but want the retention of kydex
Some of my first sheaths. There's a lot of different forms. A couple things to note: the closer the eyelets are to the balde, the tighter the sheath will be. The eyelet next to the handle is the most important. Depending on the shape of the knife, this eyelet may have to skipped to allow the kydex to flex enough to allow the knife to go in.
This is an example where I had to skip the eyelet that was closes to the handle.
This sheath had no retention. I didn't want to damage the nice scales. The customer was fine with this.
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Can't forget the Mora shot. This was probably one the nicest sheaths I made. The eyelets are set close the blade edge and almost all of the excess kydex is removed. The kydex on the handle doesn't interfere at all with the grip. And the thumb swell is just right.

I know leather is really traditional for make sheaths, but kydex does have a lot of utility in terms of retention and durability and ease of maintenance. I was really proud of this one. Made it for a neighbor.
The sheath only releases the axe with a very specific drawing motion. Otherwise there's enough retention to hold the axe even if you bounce it up and down by the sheath.
The sheath is set up with a shoulder strap. If you are not going far and expect to draw the axe many times, you can have the sheath in this configuration.
If you're hiking, you can wrap the p-cord of the strap around the handle, "locking" the sheath in place. So even if you're going through bushes, it'll stay secure.
In terms of a larger discussion of kydex vs. leather:
I love my leather sheaths for their looks and durability. But in terms diy stuff. Kydex wins out in terms of practicality, initial cost, and flexibility of design.
I've made kydex sheaths for a range of weird niche applications.
Anyone who carries tools in the backwoods would do well to learn how to make at least a basic, rudimentary kydex sheath. You can literally start with a $40 sheet that can make a dozen knife sheaths, some tin snips, and p-cord.

I ripped my decking on a small tree trunk. Bought a sheet of a product called kydex which is what they make gun holsters out of. Heated it with a torch, pressed into shape, used some rivots and wallah! Works great. Warranty was expired and I didn't want to ship across country to a repair center.