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.
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.
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.
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.
The bolsters are 416ss stainless. I clamped and drilled using the template. Rough cut them and pinned them together.
This is where a horizontal grinder really shines. Pinned together and grinding the arc where it meets the scale so they match exactly.
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.
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.
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.
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.
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.
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.
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.
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.
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.