washers on a slipjoint?

[pipecrafter]

I'm getting ready to make my first sole authorship folder, and have decided on a simple slipjoint design. I've got all the geometry laid out, understand the construction very well, but the one piece I don't know is whether washers are typically used. I've seen it both ways, so I'm wondering if there's a criteria for using them that I'm missing.

Any help is appreciated.

[Frank Niro]

I have been looking at this with the possibility of trying a slip joint myself. My understanding is if you have a milling machine you probably would go with it, otherwise the washers can accomplish what is needed. In other words, there is lots of freedom here as there is with most of knife making. Frank

[Crockett]

I made slip joint with .002" stainless washers. It used a bushing in the blade pivot hole as well. This combination made it very very difficult to assemble. The problem was making sure the washers were not pinched between the liners and the end of the bushing. It was a real pain. I'd say if you're using washers, don't use a pivot bushing.

That knife still scratched the blade when opening and closing. It was used in a rough, dirty environment and dirt and grit got in there, I figured .002" was not enough clearance. Since then I mill the liners, and I mill more than most do. I've taken off as much as .014".

If you look in the stickies here (I think in the Texas Toothpick thread) they were talking about electro-chemically etching the liners. Apparently this is the way to go!

Don

[Don Robinson]

Yep, just use your etcher. Mask off the inside fronts of both liners using electricians tape, cut the tape away around the pivot hole and the tops of the liners where the spring rides, then etch with your etcher.

Any area that might touch the blade when the blade is closed should be relieved. That is except the areas around the pivot. That becomes your built-in washers.

Don't etch the top of the liner where the spring rides.

[Kirby Bletcher]

Yea leave the washers out. Like Don mentioned its a bit of a nightmare to try and incorporate washers into a slipjoint. An alternative method is to simply relieve the liners on you 2x72 grinder.
I color the inside of my liner with red marker and starting with a 220 grit on a 8 inch wheel start lightly grinding. This is a nice way to relieved the liners if you do not own a mill or a surface grinder.
Just watch the area where you blade will pivot and imagine there is a washer there and you don't want to grind it off. Keep in mind not to grind into the area where the spring sits or you will have an ugly fit in between the liner and spring. This may seem like a crud way of doing it but ultimately its one of the nicest and hardest way to detect that anything was relieved. No step in the blade or nasty mill marks to work out on the inside of the liner. If my description is hard to understand I can draw some pictures for you to make it easier to understand. Ken Steigerwalt taught me this method but he starts with a 400 grit belt on an 8 inch wheel. Remember it only needs to be a few thousandths.
Kirby

[pipecrafter]

Thanks for the info guys! I'm actually planning on a linerless slipjoint - inspired by Todd Davison with a peened pivot. Since I don't own a milling machine, I think I'll carefully file a few thousandths off the G10 near the pivot to provide space for the washers - I plan on using .005 or .010 washers. Lunacy?

[Don Robinson]

Originally Posted by KIRBY

Yea leave the washers out. Like Don mentioned its a bit of a nightmare to try and incorporate washers into a slipjoint. An alternative method is to simply relieve the liners on you 2x72 grinder.
I color the inside of my liner with red marker and starting with a 220 grit on a 8 inch wheel start lightly grinding. This is a nice way to relieved the liners if you do not own a mill or a surface grinder.
Just watch the area where you blade will pivot and imagine there is a washer there and you don't want to grind it off. Keep in mind not to grind into the area where the spring sits or you will have an ugly fit in between the liner and spring. This may seem like a crud way of doing it but ultimately its one of the nicest and hardest way to detect that anything was relieved. No step in the blade or nasty mill marks to work out on the inside of the liner. If my description is hard to understand I can draw some pictures for you to make it easier to understand. Ken Steigerwalt taught me this method but he starts with a 400 grit belt on an 8 inch wheel. Remember it only needs to be a few thousandths.
Kirby

Yes, Kirby is exactly right about this. Years ago I either did it that way or used a Dremel sanding disk. The last few years I've been using a milling machine to relieve the liners.

I realize PC is making a linerless folder, but just in case someone else is making a slipjoint and needs this information.

[Frank Niro]

Thanks from Frank too, especially if I get around to trying one of these.

[joe sangster]

Don ,

I'm not sure I'm getting the etching picture in my mind's eye correctly . Do you leave the tape where you would have placed the washer ? Does the etcher work on titanium ?

Thanks,
Joe

[Don Robinson]

Originally Posted by joe sangster

Don ,

I'm not sure I'm getting the etching picture in my mind's eye correctly . Do you leave the tape where you would have placed the washer ? Does the etcher work on titanium ?

Thanks,
Joe

Yes, and yes. The tape masks off any part you don't want to be etched. Cut away the tape where you want the liner relieved.

[joe sangster]

Thanks , Don ! I will give it a try as soon as I get around to making my 1st slipjoint .

Joe

[doublearrow]

Joe I posted my method of etching with an etcher a while back here's some quick pictures.
I didn't have a mill so I came up with the idea of trying this and it seems to work well.
First I made a template of where I did not want to etch using a piece of liner material. In this picture I'm measuring the distances I need.

Between the circular marks is where the blade hits the liners when opening and closing.

Here I colored in the area I'm going to remove with files and a jewelers saw

Started removing material here


Here the material is removed

Here it is with blade in place just checking to make sure

[doublearrow]

Next I take the liner I wanted to etch and put black electrical tape on it

Using matching pin holes I line up the template I made up above and laid it on the liner

I used a sharp xacto knife and cut out the black tape. Here it is cut and with the template removed.

Here it is during etching

tape removed

I used fine steel wool to clean it up. It wipes right off with glass cleaner and steel wool

[Don Robinson]

Ryan, that's an excellent tutorial. Thanks for making it so clear.

[pipecrafter]

Ryan, that's incredible! Thank you so much. Now, how about a tutorial on those fine silver nail studs.

I have pipe ordes to fill this week. Hopefully my first sole authorship slipjoint will be underway this time net week - just in time for Christmas presents.