Gents liner lock WIP

Motor City Mike

Well-Known Member
Great WIP. Nicely detailed and great pictures

I just ordered a box of those cutoff wheels. Cutting lock bars is quite possibly my least favorite thing to do.

I find that the dremel diamond wheel works best but they're SO expensive.

Looks like these do a good job and the price is right.

Looking forward to giving them a try.
 

BossDog

KnifeDogs.com & USAknifemaker.com Owner
Great WIP Tracy!
How do you like working with 416SS? Does it work the same as 410?
Just read this again and to be certain we are on the same page, the liners are Ti, the bolster and spacer bar are 416ss. Many (most) folders use 410ss for the liners but I used Ti for this one.
 

BossDog

KnifeDogs.com & USAknifemaker.com Owner
I needed to shorten the pivot to length. That is the thickness of the liners, blade and washers.
I used a Pivot Lap. This gizmo has three different diameter bushings. Stick the pivot in in, push on the plunger, scrub on 240 to 400 grit, check your measurement and repeat. With this you can get square shoulders and with in a few tenths of a thou where you want to be.

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Using the height gauge to scribe the lines. I normally scribe the top spine also, mostly to check on where the point is during grinding.
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This is the fade bevel I wanted and using a 14" wheel absolutely can not be done it turns out. So the blade was toast. I dug out the mold maker stones and played a bit. That didn't save the blade at all but was good practice.
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BossDog

KnifeDogs.com & USAknifemaker.com Owner
since the first blade didn't work, I found some thinner stock in Elmax at .098" thick. Perfect! I went to surface grind them and warped the ever lovin bejeebers out of them. I've warped thin stock before and thought I had taken good steps to prevent that. I was taking only .001" per pass and had the air mist blowing on it. My passes ended up too heavy and the stock warped. I threw them. I made two more rough blanks and threw them into heat treat. I'll grind those hard which I haven't done much of but will give it a try.
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The bolsters are 416ss stainless. I clamped and drilled using the template. Rough cut them and pinned them together.
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This is where a horizontal grinder really shines. Pinned together and grinding the arc where it meets the scale so they match exactly.
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Here the template and bolsters are all pinned together. The arc does not exactly match the template which I knew it wouldn't. I will use the bolsters now to transfer to the scale material.
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Here is my bench block. It was a class project in the basic milling class I took at the local tech college. If you work on folders, you will have to tap tight fitting parts home and back out often. I have ground down a punch to 3/32" and use a small engraving hammer which is a pleasure to use.
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I snagged the last piece of 1/8" bone paper epoxy Micarta. It has been discontinued now due to California issues with some cancer causing ingredient. Too bad, it's cool stuff. I rough cut the scales full size, drill holes in the bolster area and then pin the 416 bolster to the material and scribe the arc. Fitting this tight sure looks easy. I know it isn't. I used magnifier goggles to get as close a fit as I can. We'll see later how it all fits up.
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BossDog

KnifeDogs.com & USAknifemaker.com Owner
I use this template to trace an outline.
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Here it is one side fitted. I missed several pics doing this. I'll try and get them for the other side since I have to remake it. That makes 3 or 4 parts I've had to remake which is normal for me on the first pass of a new design. I wish it wasn't that way but it is.
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The back spacer is not yet to exact thickness yet but I need to get rid of the excess material. I draw in a cut line and then grind in the arcs with a small wheel.
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Here the back spacer is in place and you can see the excess on the outside. This design has the screws fastening from the back of the knife and threads in the front liner. This way there are no screws on the front side for the space bar. It's a choice. There isn't anything wrong with screws on the front, back or both.
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Here the back space bar has been ground flush with the liners and the fit so far looks decent. The rear edges on the bolsters do not match perfectly. I pinned them together and pressed them against a 123 block vertically on a surface plate with 400 grit sand paper to sand them evening. A few very light strokes was all that was needed. I will change the arc in the bolster on the next one so the back edge is more oblique to the liner edge.
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BossDog

KnifeDogs.com & USAknifemaker.com Owner
I need to countersink the screw heads.
It turns out there are no counterbores available for 1-72 screws. I ordered a 9/64 end mill which is a .003" larger than the screw heads I am using. I didn't want to just plunge it in as that seems to never work.


In the mill (a drill press with a secured vise will work also) I use a fixture plate (I made this on the CNC but you can make one drilling and tapping a few holes in a plate also) and bring the drill bit down into the hole that is already there. Once the part is indexed, I tighten the micro toe clamps to hold the bolster in place. With out moving anything, I change the drill bit to the 9/64" center cutting end mill. I plunge the end mill .040" deep and I get a pretty decent countersink hole. I will repeat this process for the other bolster and both scales.
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That's it for a week. The lovely missus and I are going to take in some heat, beaches and beer this coming week. Stay warm.
 

BossDog

KnifeDogs.com & USAknifemaker.com Owner
The blade is already hardened and surface ground. Now time to grind it. 80 grit and lot's of dunks in water to keep it cool. I am using a 1"x10" wheel. The advantage to 1" wheels are: no 2" rash, easier to concentrate on a small portion of a wheel and belts get used more efficiently. I split a 2" belt for this wheel.
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My belts were 80 grit Ceramic, 100x, then 45x then 16x Norax followed by a cork belt with green chrome. A minute or two on the buffer more for the blue color than shine.
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A quick fit to see how the grind looks on the knife. I can live with it.
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luciusx5

Well-Known Member
Thanks for the WIP. It's amazing the amount of work that goes into a folder. Congratulations on the new baby girl! Grandkids are awesome!
 

BossDog

KnifeDogs.com & USAknifemaker.com Owner
I need to countersink the screws but I can't find a couterbore for a 1-72 button head.
I ordered in a 9/64" center cutting end mill as it is around .140" diameter and the 1-72 button heads are .138"
The process was:
Use a #48 drill upside down in the mill chuck. Using the mill table adjustments I moved the work to center the hole with the quill.

This is a pretty fancy fixture plate I made. You can make your own using about anything flat, drill and tap a few holes and make some little toe clamps.
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Once the hole is located, I switched to the 9/64 end mill and plunged it .045" deep using the mill and Z axis on the knee.

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I'm using a Willis mill but this can also be done using a drill press. If using a drill press, you have to clamp your work holding fixture to the drill press table once you line it up. If you free hand it, I promise the work will move and your hole will be off center. I had .002-.003" clearance overall in the countersink hole and the button head and I used every bit of it.
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Here you can see the countersinks. If I had a counterbore that fit, this would be trivial but it took about an hour to countersink a half dozen holes.
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Now the test. Screw it back together and make sure everything fits. I got lucky. I found only one screw that rubbed a bit on the side going in but it went in and didn't skew the scale from the previous fit.
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I could have used a larger drill bit but that leaves a V bottom and usually jumps all over the place with chatter marks on the edges of the holes. Also the Z (up and down) axis depth of drilling is horrible on a drill press unless you set up an indicator. I have in the past done this with a hold down plate and drill bit that I ground flat but the end mill definitely does a better job. You don't need a mill for stuff like this and a mini-mill eats this stuff up.
 

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Jim Moenck

Well-Known Member
I need to countersink the screw heads.
It turns out there are no counterbores available for 1-72 screws. I ordered a 9/64 end mill which is a .003" larger than the screw heads I am using. I didn't want to just plunge it in as that seems to never work.


In the mill (a drill press with a secured vise will work also) I use a fixture plate (I made this on the CNC but you can make one drilling and tapping a few holes in a plate also) and bring the drill bit down into the hole that is already there. Once the part is indexed, I tighten the micro toe clamps to hold the bolster in place. With out moving anything, I change the drill bit to the 9/64" center cutting end mill. I plunge the end mill .040" deep and I get a pretty decent countersink hole. I will repeat this process for the other bolster and both scales.
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That's it for a week. The lovely missus and I are going to take in some heat, beaches and beer this coming week. Stay warm.
Boss, I looked on RB Johnson's site, and he as the counter bore bits for 1-72. I think I got mine from him years ago.
 

BossDog

KnifeDogs.com & USAknifemaker.com Owner
sigh...This build is a bust. The bolsters were even when I started out but they thinned out unevenly and there is no way to save this build. It will go in a drawer with the other folder corpses I have carefully accumulated over the years.
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This is a design issue and I should have known better as I've had this bite me in the past. The bolster arcs back to nearly even with the spine and it gets too thin so it ends up uneven. I will take the bolster pattern and change it up so it has significantly less swoop to it and can be finished with out a super thin back end.
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Shortening screws. These come through the backside, the space bar and both liners. They are ground flush to the front liner and then the front scale can go on.
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I also needed to shorten the pivot screws. I dug out my screw cutter. Allan Elishciwitz (sp?) puts these out in batches occasionally. They will shorten screws by snipping them off after you screw them into the holes. I don't use it that often but it does come in handy.
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