How To Slipjoint washer tutorial posted

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Brady13

Joined
Apr 30, 2019
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Hey guys, was thinking of putting up a little how to on brass washers, wondering if anyone would actually be interested and if you would rather it on her through Flickr images or on Instagram

here’s all the pics in an album. I don’t have photbucket so I can’t put them up with every step but this should work
Also sorry they aren’t in order but after you go through the steps they should make sense. If not just ask

https://www.flickr.com/photos/189139927@N03/albums/72157716630067006/

1: get all your tools ready you’ll need some files to shape the washer, a drill press to drill the Centre hole and a bit of your choice, a square to make sure your press isn’t out of alignment, sandpaper, granite surface plate, a scribe, a hammer to flatten the cutout, tin snips to cut your washer out of the brass. And there’s a few more specialty tools as well.
2. first thing you need is to get the material of your choice, mine was brass, I started with .030” thick too much thinner and you could run into problems while shaping the washer with your file i.e. bent washer
3. Drill a hole through your material making sure you have enough meat on each side for the size washer you need
4. Now, that piece of micarta I have in the photos has a hole drilled in it, a piece of flattened mild steel would work better, drill a hole through your little steel plate to the OD you want your washer. Mine is 1/4”. Then Center it around the hole you drilled in your brass and scribe around it, get it as centre as you can, the accuracy of the washers all depends on how much time you put into them
5. Now just cut your washer out of the brass making sure not to hit the lines
6. With the snips the cutout will be pretty bent and mangled, I just put it on my surface plate and LIGHTLY tap it until it’s flat
7. Now your going to put the square piece you have in the vice and knock all the corners off, then proceed to rounding it and getting down to your lines.
8. Now your ready to lap your washer, you’ll see in the photos I have a big chunk of aluminum I drilled a hole through, in that hole is a piece of brass rod that I slip the washer onto, then you level it with the aluminum block place it on your surface plate with sand paper and start sanding to the thickness you need, you can get them very thin this way. I typically make .005” thick washers. Now I’m sure you could build a better jig to lap then this but this works. I am designing one so if it work I’ll post the designs.
9. Now your done!!! Now you can say you handcraft you own washers and add 2-3 cents to your knife:)

sorry if any of this didn’t make sense if not feel free to ask questions please. I’ll answer them best as I can.
 
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Any form is MUCH better than those social media places. I'll never see it there, and the times I have tried to see it just didn't work near so well as a forum page. Please do post your WIP on washers.
 
Well over the next week or so when I have some time I’ll get it all organized and post it up here. Thanks for the feedback guys
 
Wait washers or bushings? I havent see washers with slipjoints. wIth slipjoints how it works is this:
  • Handles/Liners get, for instance, a 1/8" pivot hold drilled. Blade will have a PRECISION 3/16" hole. For this youd use a bushing with an ID of 1/8 and a OD of 3/16.
  • In the end the blade will rotate around the BUSHING, not the pivot pin. THe pivot pin is there ONLY to give you something to peen and tighten the frames.
  • Lets say your blade and spring are EXACTLY .093 thick JUST before final assembly (with a tiny bit thinner to front of spring)
  • You will now measure the thickness of your tang and find its widest point, say .0930. You will then use a bushing lapping device to lap the width of that bushing to .001 thicker than your blade. .0005 now of that bushing now extends on both sides past your blade tang hole
  • When you now peen your front pin there is NO way to bind up your blade. You could smash that pin with a 4# sledge and all you'd be doing is your intended purpose: Peen the pin so firmly and completely you hide that pin 100% when blended.
  • The bonus here is that since your bushing is wider t the blade when you are actually doing is forcefully sandwiching the BUSHING between the liners. That then becomes your permanently anchored pivot. The blade spins freely around the bushing. The bushing never moves and nothing rotates around that main smaller pin at all.
Tis requires a machine fit on your blade/bushing for zero play. Undersize, ream and lap the bushing hole and polish the OD of the bushing till it slide fist with no binding into that hole.

Final assembly a breeze. Slam those pins HARD and swell the pins with no use of annoying spacers you eventually crush between the blades, hammer blows a bit too hard the bind your blades, etc etc.

TOny bose did a construction series exlaining this that isnt linked. I've lapped the pics off these pages a LOT. He's the god of slipjoints so do what he says. Only thing I dont have the anal retention to do is re-locate the positioning of the bushing every time:
http://boseknives.com/pvtbushing/index.htm
 
David Schott said:
TOny bose did a construction series exlaining this that isnt linked. I've lapped the pics off these pages a LOT. He's the god of slipjoints so do what he says. Only thing I dont have the anal retention to do is re-locate the positioning of the bushing every time:
http://boseknives.com/pvtbushing/index.htm
Click to expand...
Keep in mind though, that attention to detail of marking the bushing in relation to the blade and assembling the same way everytime could be the difference between a good knife and a great knife.

Just curious, where do you get 3/16" bushings with 1/8" holes?
 
Signalprick said:
Keep in mind though, that attention to detail of marking the bushing in relation to the blade and assembling the same way everytime could be the difference between a good knife and a great knife.

Just curious, where do you get 3/16" bushings with 1/8" holes?
Click to expand...
I guess in what way? If my pivot is reamed and lapped and the bushing is barey a slip fit and the spring provides constant downward pressure on that blade, what do i gain? I get staking so no chance of bushing slip.


I jus swapped even to 3/32 bushing with 3/16” OD...easier to hide pins and no real peening strength loss. I got mine at K& G knife on recriminations here.
 
David Schott said:
I guess in what way? If my pivot is reamed and lapped and the bushing is barey a slip fit and the spring provides constant downward pressure on that blade, what do i gain? I get staking so no chance of bushing slip.


I jus swapped even to 3/32 bushing with 3/16” OD...easier to hide pins and no real peening strength loss. I got mine at K& G knife on recriminations here.
Click to expand...

I get the same bushings from K&G. My guess is that if you tune your spring to be flush with the bushing in a particular orientation, on the chance the hole in the bushing isn't perfectly center it would give you a different reading on your RFI everytime unless you "time" it as Tony explains. I'm sure this step in the process was learned the hard way. Just a hunch on my part though.

Hengelo_77 said:
Blade + 2 washers = spring thickness
Click to expand...

The only thing I don't get about doing washers over bushings is with the bushing the blade pivots on the bushing and not the pin as Dave explained. This ensures the pin won't slightly rotate over time and reveal that ghost ring on your bolster or rosette. To me washers dont have this added benefit because the blade is still pivoting on the pin.
 
Signalprick said:
The only thing I don't get about doing washers over bushings is with the bushing the blade pivots on the bushing and not the pin as Dave explained. This ensures the pin won't slightly rotate over time and reveal that ghost ring on your bolster or rosette. To me washers dont have this added benefit because the blade is still pivoting on the pin.
Click to expand...

Exactly and why you need a good union blade/bushing. If you get binding there you risk it trying to rotate the bushing itself, however unlikely, putting pressure on the pin and risking the ghost ring...at least in my limited experience. Slipjoints are a terrible, terrible rabbit hole in anal retention.
 
Hengelo_77 said:
Bushings and washers have different functions
Click to expand...
Understood but as it relates to pinned slip joint knives I dont see how a washer would be a better option over a bushing. You have to do about 90% of the same work to get it right but with less benefit. Now for a screw construction slippie I totally get it.
 
Hengelo_77 said:
Bushings and washers have different functions
Click to expand...

I understand this but you had said blade+2washer=spring thickness. Isnt there a lot of effort achieving this without a surface grinder or starting with different thickness materials? Otherwise how would you have a seamless spine?
 
David Schott said:
I guess in what way? If my pivot is reamed and lapped and the bushing is barey a slip fit and the spring provides constant downward pressure on that blade, what do i gain? I get staking so no chance of bushing slip.
Click to expand...

The reality is sometimes everything is not concentric.
Sometimes the tang hole or bushing may have a few thousands of slop.

Last couple I made did not, but usually they have a couple of thousands off somewhere along the path of the bushing and tang interface.

That is why you make an index mark on the bushing, I just scribe a line at 6 O'clock to be sure what I see at the back spring and liners is always the same.

This is how I measure if there is any slop with the bushing and tang hole.

On my rise fall/Rupple Jig indicator I place the bushing, blade and spring.
I zero the indicator on the open position.
Move the blade to half stop allowing the bushing to rotate with the blade.
Hold the bushing down and do not let it move, then move the blade back to open.
Look at the indicator, did the reading change from zero?
Now repeat, moving the blade to close, allowing the bushing to pivont on pin.
Hold bushing down and move the blade all the way back to open.
Did the indicator return to zero?

If there is a change in the reading I rotate the bushing, on the indicator to the lowest reading point below zero. This way if the bushing moves it will only move the spring up and not down into the liners upon completion.

Hope that makes sense. I have not seen anyone else do this. It is something I worked out
 
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