Fine-tuning your Kydex gear
A lot of people have kydex gear that is too loose (most commonly), or too tight (particularly in the case of knife sheaths). Like any friction or tension based mechanism, all kydex will eventually loosen and lose its form slightly over time. So I thought I’d make a little guide on how to fine-tune your kydex gear without ruining it, or worse having to send it back to the maker. Some gun holsters, particularly those that are extensively shaped to the trigger guard and grip, unfortunately can’t be easily fixed at home, though.
You will need the mag holder, sheath, or holster, one or more high-tension spring clamps of various sizes (in the demonstration I used Harbor Freight 1” heavy duty spring clamp item 66055), and a hot blowdryer (not a heat gun – most heat guns are too hot). Larger clamps are generally more useful, but a smaller clamp could be used for creating a small dimple, or otherwise super-fine-tuning your gear.
Lots of people don’t realize their kydex is too loose. For a pistol, the gold standard is going through some force-on-force training, preferably including some weapon retention training and grounded work, and verifying that the gun will stay in its holster. For a mag holder, the same standard applies. In either case though if you hold the holster upside down and shake it vigorously, the gun or mag should remain inside it. For knife sheaths, which obviously can’t be used in force-on-force, use the shake test and err on the side of slightly difficult to remove. As you’ll see there’s an easy way to fix sheaths that are too tight, but again, they are typically too loose.
After testing your gear, if it’s too loose, the first step is to identify the places you want to tension it. In a typical “clamshell” configuration, the tension comes from the “U”-shaped side (the side opposite the “mouth” of the “clamshell”). With most mag holders and knife sheaths, the top (the opening where you insert the mag or knife) should also be slightly narrower than the bottom to increase friction. In this CCC mag holder, I placed the spring clamp in such a way as to tighten the “U” by placing the clamp opposite the “U.”
With a narrower item you would probably need to place the clamp on the “U.” As a rule of thumb, usually you also want to place a clamp on the opening, or the widest point of the kydex item. Be careful not to flatten out a formed piece of kydex, though.
After clamping, turn the blowdryer on “high” and point it primarily at the “U.” You can hit it from the inside, the outside, and all angles, but be careful not to heat up the parts that you don’t want to reform. When the kydex is too hot to leave your finger on for more than a half-second or so, walk away and allow it to cool to room temperature.
That leaves me with a too-tight mag holder; the mag will barely fit in there:
My next step is to insert an empty mag and repeat the process, sans clamp. This leaves me with a mag holder that is appropriately tensioned; I can insert the mag relatively easily but it won’t come out if I don’t want it to:
So to recap, you want to first over-tension the “U” and/or the friction points (like the opening on a knife sheath). Do this one area at a time: blow-dry, allow it to cool, and repeat elsewhere. If you have, for example, a kydex sheath that is partly formed around the guard of the knife, after tensioning the "U" you would want to insert the knife, clamp the widest point, and blow-dry, walk off, and come back, then test it. Your gear should now be overly tight, or it may be just right. It’s actually better to make it too tight, then insert the item it holds, and blow-dry, let it cool off, and test it with the shake test (and make sure you can get the item in fairly easily). If it’s still too tight, blow-dry it and insert and remove the items several times while it’s still hot.
In some cases you may opt to use more than one clamp at once, or alter the methods outlined above; that’s fine, just be sure not to mess with the areas of the item that do not aid with retention. In the case of high-quality kydex gun holsters made of thick kydex shaped to the trigger guard, you either need to send them off to the maker, or use a kydex press. There are instructions online to make a DIY kydex press cheaply.
The only real way to screw this up is to totally melt your kydex using a heat gun, or to flatten out a formed area.
A lot of people have kydex gear that is too loose (most commonly), or too tight (particularly in the case of knife sheaths). Like any friction or tension based mechanism, all kydex will eventually loosen and lose its form slightly over time. So I thought I’d make a little guide on how to fine-tune your kydex gear without ruining it, or worse having to send it back to the maker. Some gun holsters, particularly those that are extensively shaped to the trigger guard and grip, unfortunately can’t be easily fixed at home, though.
You will need the mag holder, sheath, or holster, one or more high-tension spring clamps of various sizes (in the demonstration I used Harbor Freight 1” heavy duty spring clamp item 66055), and a hot blowdryer (not a heat gun – most heat guns are too hot). Larger clamps are generally more useful, but a smaller clamp could be used for creating a small dimple, or otherwise super-fine-tuning your gear.
Lots of people don’t realize their kydex is too loose. For a pistol, the gold standard is going through some force-on-force training, preferably including some weapon retention training and grounded work, and verifying that the gun will stay in its holster. For a mag holder, the same standard applies. In either case though if you hold the holster upside down and shake it vigorously, the gun or mag should remain inside it. For knife sheaths, which obviously can’t be used in force-on-force, use the shake test and err on the side of slightly difficult to remove. As you’ll see there’s an easy way to fix sheaths that are too tight, but again, they are typically too loose.
After testing your gear, if it’s too loose, the first step is to identify the places you want to tension it. In a typical “clamshell” configuration, the tension comes from the “U”-shaped side (the side opposite the “mouth” of the “clamshell”). With most mag holders and knife sheaths, the top (the opening where you insert the mag or knife) should also be slightly narrower than the bottom to increase friction. In this CCC mag holder, I placed the spring clamp in such a way as to tighten the “U” by placing the clamp opposite the “U.”
With a narrower item you would probably need to place the clamp on the “U.” As a rule of thumb, usually you also want to place a clamp on the opening, or the widest point of the kydex item. Be careful not to flatten out a formed piece of kydex, though.
After clamping, turn the blowdryer on “high” and point it primarily at the “U.” You can hit it from the inside, the outside, and all angles, but be careful not to heat up the parts that you don’t want to reform. When the kydex is too hot to leave your finger on for more than a half-second or so, walk away and allow it to cool to room temperature.
That leaves me with a too-tight mag holder; the mag will barely fit in there:
My next step is to insert an empty mag and repeat the process, sans clamp. This leaves me with a mag holder that is appropriately tensioned; I can insert the mag relatively easily but it won’t come out if I don’t want it to:
So to recap, you want to first over-tension the “U” and/or the friction points (like the opening on a knife sheath). Do this one area at a time: blow-dry, allow it to cool, and repeat elsewhere. If you have, for example, a kydex sheath that is partly formed around the guard of the knife, after tensioning the "U" you would want to insert the knife, clamp the widest point, and blow-dry, walk off, and come back, then test it. Your gear should now be overly tight, or it may be just right. It’s actually better to make it too tight, then insert the item it holds, and blow-dry, let it cool off, and test it with the shake test (and make sure you can get the item in fairly easily). If it’s still too tight, blow-dry it and insert and remove the items several times while it’s still hot.
In some cases you may opt to use more than one clamp at once, or alter the methods outlined above; that’s fine, just be sure not to mess with the areas of the item that do not aid with retention. In the case of high-quality kydex gun holsters made of thick kydex shaped to the trigger guard, you either need to send them off to the maker, or use a kydex press. There are instructions online to make a DIY kydex press cheaply.
The only real way to screw this up is to totally melt your kydex using a heat gun, or to flatten out a formed area.
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