Friction folder parts and how to, please explain how to measure and fit hardware

N.N

N.N

Well-Known Member
So i've been thinking of doing my first friction folder and I've come to a point that I don't know exactly how to figure out....I've not yet actually done any work at this point, just research and trying to make everything work in my head first so I know what to order.

So here's where I'm at. I can draw out a design to get a basic shape and make that work on paper, lining up the holes, the stop pin the pivot etc.,

where I draw a blank is when I start thinking about exacly what pivot, stop pin or other hardware I need and more so, what sizes.

So If i'm going to use a 1/8 inch steel for the blade and 1/8 g10 for each side of the handle that's a total thickness of 3/8 (1/8x3). But in shaping the handle, i'm going to inevitably take some of that off. If i want my hole to be 3/16 pivot, I get a 3/16 x 3/8 (length) pivot right? would that work if and I can shorten the screws if the handle material gets thinned out a bit?

Will this work? http://usaknifemaker.com/folding-knife-parts-c-30/pivots-and-stand-offs/pivot-barrel-3-16-x-3-8-for-folders.html#.U8hLgUDDWvQ

Or would this be better (although out of stock) http://usaknifemaker.com/folding-knife-parts-c-30/pivots-and-stand-offs/chain-ring-bolt-set-3-16-dia-x-50-l.html#.U8hM1kDDWvQ

I would love to hear how you guys measure this stuff out when making folders. Or Am I just overthinking this? Thanks for the help.
 
I hope you get some good info. I just started one this week and ordered some 3/16 pivots and some 1/8 for stop pin and today I got around to working on it and I had to shorten the pivots and the screws on the belt sander it works I guess but I think I needed to do more research before I ordered them.
 
I think shortening pivots, stop pins and screws is a necessity. I don't think you want to plan your knives based on the available lengths of the hardware. They make them plenty long and count on makers adjusting them to the desired length. I've never used a pivot, stop pin or screw that I didn't have to shorten. :)

You guys are on the right track.

There's not much to measure when ordering hardware. Design your knife to fit the hardware you want to use..................or use hardware that fits your design. Either way works. Have appropriate tooling so your pins fit as tight as possible for the best accuracy. Buy pivots and pins that are plenty long. Then shorten and adjust lengths as needed to suit your knife.
 
Mr Doyle provided sound advice.

Engineer connections around the machine or tool. The Law of Connections applies to anything from building a birdhouse to engineering the space shuttle.

"Follow the Law" and all will be well.
 
Last edited by a moderator:
Just received my parts order for my first one from Beth (she's the best). Working out the design in kydex next. I also will be using a 3/8" design with G10 liners. Paper prototype works ok.

Good luck with your project! First are always fun...
 
I have another question related to frictions. Do you install the back spacer after you heat treat and finish the blade so you have the thickness right or can it be done pre HT?
 
You can make it prior to heat treat but if you grind, sand or surface your ricasso/bearing area after heat treat, you will want to adjust your backspacer to match.

Backspacer should equal your blade thickness plus both of your washers. So if you have an 1/8" blade and use .010" thick washers your backspacer should be .145"
 
That's what I was thinking J.D. I figured it would change due to removing the decarb after HT. Thanks. I might make a a temp backspace and temporary pin it just so I can carry it a bit to see how it feels in the pocket.
 
Thanks guys for the help, I think I was over thinking it a little. I figured I could always shorten screws to fit, I just wanted to ask some opinions.

so what works better and is there a reason for it? pivot barrels or chain ring bolts or what, is there a reason to use different types of screw/pivot?

What would you recommend for pins/screws or whatever for the back spacer?
 
The pivot is kind of personal preference. What do you like the looks of? As long as it's fairly precise it should work. It would be good if it was hardened.

I pin AND screw my backspacer in. A couple of 1/16" precision locator pins keeps it in the exact same spot with the liners every time and then a couple of 1-72 or 2-56 flathead screws counter sunk into the liners keeps it drawn tight to the liners. I'm sure others have different methods and that's just how I do it.
 
Right now I'm thinking that I should probably keep it simple with 3/16 (http://usaknifemaker.com/folding-knife-parts-c-30/pivots-and-stand-offs/pivot-barrel-3-16-x-3-8-for-folders.html#.U8mP8EDDWvR ) pivot barrel and screws for the pivot and then use the same thing but the 1/8 size for the spacer with a simple 1/8 ss pin for the stop pin. Since I'm not using steel liners, that's about the best I can come up with to keep it tight without having to epoxy it together. I'm just worried about having to take too much off them to make them fit.

That should work, right... shouldn't be too hard should it?

I had thought about trying the small 2-56 screws for the spacer, but I don't have a tap and I'm not sure I'm going to get into that quite yet, at least until this one turns out ok and I decide to do more.
 
It should work. I would use hidden 1/16" alignment pins for the backspacer. All the way through the spacer and just barely into the backside of each scale. 3 of them in there would do wonders for precision and repeatable location. Then you could use the 1/8" barrels and visible screws that you mention for holding it together from the outside.

That's just how I would do it if I were making one exactly as you described. There are lots of ways to get to the same end result. :)
 
You must log in or register to reply here.
Back
Top