Phosphor Bronze Washers - best way to cut?

REK Knives

REK Knives

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Knifemaker / Craftsman / Service Provider
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I have worked with, on, and made folders for years. I've dealt with a lot of pb washers in my time. One thing I've noticed, especially about aftermarket washers is that they aren't flat and typically have burrs/bends.

The best quality I've found is TiConnector washers, but they don't have all the sizes.

I think best would be wire EDM but I know my place can't cut non-magnetic stuff.
 
I think they punch them out like cookies but maybe if the tooling is sloppy you'll get ones that are dished or otherwise nasty.

Maybe the nicer ones are going through some post production treatments. That's why they're more precise.
 
Have you checked Boker's Washers (not the knife brand, an actual company that makes washers). When I was still making folders that is who I ordered from. I tried using the optical punch...it did not work well. I did find that a few laps on 2K-3K sandpaper and a granite plate took care of any surface issues.
 
Why not mill them on a CNC? Stick a sheet of PB down on a flat spoil board with some double sided tape, and then mill the ID/OD as required. You could even add a reaming and/or deburring op as needed, but with a sharp endmill, I imagine they'd come out nearly perfect with a standard contour path.
 
navman said:
Have you checked Boker's Washers (not the knife brand, an actual company that makes washers). When I was still making folders that is who I ordered from. I tried using the optical punch...it did not work well. I did find that a few laps on 2K-3K sandpaper and a granite plate took care of any surface issues.
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Just checked and the website isn't working for me. I don't need a thousand or anything so not sure they would want to mess with it (or if I could afford it lol)
 
Drew Riley said:
Why not mill them on a CNC? Stick a sheet of PB down on a flat spoil board with some double sided tape, and then mill the ID/OD as required. You could even add a reaming and/or deburring op as needed, but with a sharp endmill, I imagine they'd come out nearly perfect with a standard contour path.
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That's a great idea,I'll have to look into it!
 
REK Knives said:
…I think best would be wire EDM but I know my place can't cut non-magnetic stuff.
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I am quite curious about this statement. I have seen plenty of titanium parts wire EDM cut and have never been told that non-magnetic materials are problematic. Non-electrically conductive parts, yes, absolutely problematic.
Plenty of sources mention cutting copper alloys.

re punching, yeah, that’s the cheapest way, and thin, soft, material is difficult to punch cleanly. The thin soft material will tend to smear between the punch and die if they are not very close fit…which cost more to tool.

I am surprised that they could not be laser cut pretty well. We have laser cut steel stator laminations for electrical motors and the tolerance and finish is about the same as punched.
 
C_Claycomb said:
I am quite curious about this statement. I have seen plenty of titanium parts wire EDM cut and have never been told that non-magnetic materials are problematic. Non-electrically conductive parts, yes, absolutely problematic.
Plenty of sources mention cutting copper alloys.

re punching, yeah, that’s the cheapest way, and thin, soft, material is difficult to punch cleanly. The thin soft material will tend to smear between the punch and die if they are not very close fit…which cost more to tool.

I am surprised that they could not be laser cut pretty well. We have laser cut steel stator laminations for electrical motors and the tolerance and finish is about the same as punched.
Click to expand...
Laser leaves bad burrs but it would probably work.

All I know is my edm company told me they use some sort of magnetic fixture for the parts they cut so they don't cut non magnetic parts.
 
drill the inside holes undersize, deburr them ,ream to exact size, cut them square, stack them onto your custom holder
spin them on your lathe to make all of them the same outside diameter...
i have had to make my own washers for 20 years... because no one offers the 5-7 different thickness washers i need for different knives
 
I’m neither a machinist nor knife maker, but lathe was my first thought as well. I have seen WiP threads of people making custom washers and bushings on a lathe.
 
They can definitely be made on a lathe but getting them deburred in the lathe and maintaining a really tight tolerance on thickness and flatness would be difficult.
 
Rack Robotics has a kit to convert 3d printers into small wire edm machines, supposedly works for any conductive materials. Relatively affordable as well.
 
Did you check with TiConnector if they can make you some, Josh ? Not dealing with them in your volumes, I bet, but they seem like great people.
 
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