Saturday, May 31, 2014

KN7 CHEF'S KNIFE - KEYHOLE BOLSTER

For the second chef's knife I wanted to try something a little different. I've seen the keyhole bolster on some high-end knives and wanted to give it a try. I made a plan to make the bolster pieces out of 304 stainless.

 I started with a piece of 0.25" x 1.5" 304 stainless and cut off two pieces about 1.75" long.
With the belt grinder I trued two sides, then traced and shaped the belly curve.
 Once the basic shape was made, I marked where the pins will go and decided on a place for the keyhole. The L (left) piece is shown.
I clamped the two bolster pieces and drilled a pilot hole. Then I went through with a 3/8" bit.
Once the main hole in the keyhole was drilled all the way through, I lined up and clamped one piece back on the tang.
Now to drill the pin holes with a cobalt #30 bit. Once the one piece has its pin holes, I place some temporary steel pins in to secure the piece to the tang. Then clamp the second piece when the edges are matched. I then remove the temporary pins and drill the second piece.
The pin holes perfectly match. This was the objective.
Now to finish the keyhole. I used a protractor set to about 65° and marked with a permanent marker. I set a piece in the vise and cut with a hacksaw. Repeating for the second piece.
Rough cut. These get pinned together and shaped a bit better with the file.

Now the pieces are pinned back on the knife and checked for alignment.








Of course this is only half the job. The other half is fitting the scales into the keyhole.




KN7 CHEF'S KNIFE - KEYHOLE SCALE FITTING

The wood for the scales is stabilized Aboyna burl from WoodStabilizer.com. I believe this is presentation grade as only the one side is heavy on burl. I wanted to show off the burl area at the tail end of the knife.

I taped up the blade and tested the scale against the tang, looking for a good placement. The trick here is to show off the burl while avoiding the two inclusions in the wood.

I held everything in place and traced the keyhole with a mechanical pencil.
I traced outside the pencil line with a fine Sharpie, then went over to the scroll saw and started notching away.
Once roughly cut, at touched up what I could on the disk sander. The shape doesn't really lend itself to any kind of flat surface sanding.

I clamped it to my toggle clamp board and positioned a lamp behind so I could better see the original pencil line. If you want to use a fine Sharpie to enhance the line go right ahead.







With a series of files and needle files I went very carefully around the line to perfect the shape. I found it works best if you angle the file slightly in at the bottom. This will create a slight taper and you can start fitting the bolster piece on and test the fit.






This is the left side scale done. Repeat the process for the right side scale and try to match the left.









 After finishing the second scale, I temporarily pinned the bolster and scales with wooden dowel.

Friday, May 30, 2014

KN7 CHEF'S KNIFE - ETCH AND HANDLE ATTACHMENT



 Before pinning the bolster and scales on I wanted to add the maker's mark and the steel type mark. I did this with my stencils and electrolytic etcher.





Added "AEB-L" mark on the right side of the blade, opposite my mark.





This is what Brownell's Acraglas looks like when it arrives. I won't be using the dyes, but the cups and sticks will come in handy. This kit makes two fluid ounces. I will be using about 1/2 an ounce per knife, so I measure it with 4 bottle caps to one bottle cap.




Applying the epoxy to seal the scales and bolster pieces on. I slathered it up and pressed the pins in. I used a carpenter's vise to squeeze them in and then tapped them near flush with a hammer.

Like any glue-up, put some gloves on.






A gentle clamping pressure and we wait for it to set. I wipe around the front of the bolster to remove any epoxy

Some notes on Acraglas. The ratio is 4 parts to 1. The mix time is 4 minutes. Working time is 15 minutes depending on temperature. Colder is slower. In my experience the working time was closer to 30 minutes, but it's cool in my shop.

Thursday, May 29, 2014

KN7 CHEF'S KNIFE - FINISHING


After the big glue up, I worked the bolster with a few different files, then some 220 grit sand paper. I wanted a more rounded shape.

This is after some wet sanding.
320 grit was the last step before buffing with black and green abrasives on the buffing wheel.



































Monday, May 19, 2014

DH21 - PATTERN & INITIAL SHAPING









The DH21 is a shape I really like and hope to make a few of these eventually. This initial iteration begins life as a piece of 5/32" 154CM. This should end up in the 8-3/4" overall length range.


I start with the printed template and select the appropriate size for my piece of steel. I cut out and glue the paper to a piece of 1/4" high-ply plywood.

Once the pattern is shaped, I lay it on the steel to check placement and dimensions. Looks like a little waste, but this will be fine.







I sand the face of the steel and apply some layout fluid. Once dry, I clamp the pattern down and scribe around it with a scratch awl.








After a few minutes on the 'hogger' belt the blank is taking shape. I mark, punch and drill the pin holes. For this knife I'll use 3/16" pins and thong tube.







Some refinement in the shape and the we're almost ready to start removing some serious metal with a flat grind.







Sunday, May 18, 2014

DH21 - FULL FLAT GRIND & HANDLE PREP

As I am still learning to use my new grinder, I opted for a full flat grind on this knife. I am still working out the techniques on plunge line and what belt grits to use. I did the full grind up to 120 grit.








I am going to use the camo scales I made in my DIY Micarta project.  I trace an outline of the tang on the scale pieces with paint pen or permanent marker.






Heading over to the band saw, I rough out the shape there.

Ditto for side two. I like to mark them now with RO and LO for "Right Outside" and "Left Outside" so I don't mix them up going forward.

Clamp one scale and drill one hole. Insert a pin or dowel into that hole to fix the scale and tang together, then drill a second hole. Insert a second pin and drill the third hole. I use drill bits for pins or sometimes wooden dowels.



I am always trying hard to make sure the front of the scales line up perfectly. I usually clamp these together and shape them on the belt sander at the same time. This way the alignment should be perfect. If not, when I take the scales off, I will re-pin them and touch up the alignment sans blade.








Using wooden dowels at this stage helps hold everything together and they are easy to pop out to remove the scales.

I like to take the rough scales to about 1/8" of inch to the steel. This will allow the real finishing to happen after heat treating when they are pinned and epoxied on.


Now to get the blade finished up to 400 grit or so before heat treatment.



Saturday, May 17, 2014

DH21 - HEAT TREAT AND HANDLE WORK

For heat treatment, I placed the knife in a stainless steel pouch and it went into the oven at 1060°C for 15 minutes. I then removed and quickly cooled with two copper plates while blowing with compressed air. 

Then I immediately placed it into my tempering oven for two, two hour cycles of 200°C. I should be in the Rockwell 59C range for hardness.

 The blade looks like schmeg with the oxidization on it. I take to it with some sandpaper and WD-40. Starting at 220 grit.
And ending up at 400 grit. I don't want to go too fine as I am looking for a matte finish.
A quick wipe with acetone and let it dry. Then apply the stencil as straight as possible. Masking tape holds it down. I press the stencil down with my fingers and wipe then etching pad across, from left to right. I like to go 10 times on 'etch' then switch my etcher to 'mark' for 5 passes.
 The result is a nice dark etch that will clean up well.
I have some stencils for different types of knifemaking steel from Ernie Grospitch (Blue Lightning Stencils) that I use to mark the blades.
 Applying some tape to protect the blade is a good thing. I like to tape right up to where the scales go so any excess epoxy squeezes out on the tape, not the blade.
Pins in, epoxied up and a gentle squeeze. Once it's oozing, I like to wipe the excess with wet wipes.



I hit the pins with a belt grinder to get them nice and close to the scales. The handle is now ready to start some finer sanding on.