I decided to make something for myself. Michigan made knife number 9 is an antler tine friction folder. I have kept very few of the knives I’ve made and this is the first one from Michigan that I’ll keep. I wanted something that I would realistically use a lot. I use a certain type of knife for my profession. The next knife I use the most is a kitchen knife. Finally, I use a knife to open a lot of boxes.
Antler Tine Friction Folder
I wanted the knife to be both useful and something I was likely to carry around. For that to be the case I needed to figure out how to make a pocket knife. I lack the tooling to make anything super complicated, so I decided to make what is called a friction folder. This is a type of knife that does not have a spring or a locking mechanism but is held open both by the way the knife is used and by the hand holding pressure on the tang of the knife as it rests in the handle. It is held closed by a small amount of friction, which can be set to your desired level by tightening the pins. More on that later.
How to Make a Friction Folder Work
Let me start by saying that no one taught me how to make this. I had to figure out how these work on my own, so some of my terminology may be a little off, but this is a working friction folder, so I know the concepts must be right. First, you need a blade which connects to a tang. The tang needs to be long enough so that when you close your hand on the handle, there is no problem keeping the tang depressed into the handle. This won’t be a problem, because when you cut something, you put pressure on the edge of the blade, which will force the tang downward into the handle. Next you need a pivot hole for the folder to rotate on. A pin will go through a hole on the handle and the blade, allowing it to rotate open and closed. You will need another pin, which the tang will rest on when the blade is open, preventing the blade from opening too far. You’ll also need a notch in the tang for the pin to come to rest in. When the knife is closed, you want the blade to stop on the open/closed pin without dulling the blade, so a notch on the bottom part of the blade is needed.
Here is a real key: The distance from the pivot pin to the closed rest pin notch on the blade needs to be exactly the same as the distance from the pivot pin to the open pin rest on the tang. Obviously it follows that the open/closed pin needs to be that same distance from the pivot pin. The rest is designing a blade to fit your particular use (box cutting) and your handle.
The handle needs to have a slot in it the width of the blade. That slot needs to be as long as the distance from the pivot pin to the end of the tang so that the tang can come to rest inside the handle when it is opened. You need another partial slot on the bottom side of the handle that is not made all the way through, but just enough so that the blade, when closed, rests in the slot. It should be slightly narrower than the blade so that the blade wedges into it when closed. The friction helps the blade stay closed.
Above is a photo of the finished product, open. The two pins are smushed out a bit like a rivot and the pivot holes are slightly countersunk. You can very carefully adjust the tension on the blade by hammering each pin a little more.
Above is what the blade looks like when it is closed. It is important that friction holds the blade closed so that it doesn’t open in your pocket. That friction can be adjusted by flatting the rivets just a little more. As the blade loosens over time, a couple gentle whacks with a hammer will restore the tension. Obviously, care should be taken so that the tang is rounded off a bit so as not to skewer your leg when it is in your pocket.
And there it is partially opened. The 00 on the tang signifies that I made it for myself and that it isn’t for sale.