Vet’s Knife Work in Progress

IMG_4689
This 4.5” was made for a local veterinarian. The blade is 440C stainless steel, the guard and  pins are 416 stainless steel, and the handle is black linen micarta. I chose these materials because of their ability to withstand corrosive sanitizing chemicals, such as those used on veterinary equipment.

IMG_0315

1. The knife after forging

The first step in making this knife was the forging process. I forged the knife using wood as my fuel source, as it is cleaner than coal, and does not impart impurities into the steel, as coal might. I found that, when forging stainless, it is critical to keep it within the lower forging temperatures, as too much heat can lead to the steel cracking. I also found that 440C is less prone to cracking when forged with more blows of a lighter hammer, rather than fewer blows with a heavy one.

After forging comes the rough grind. I ground this knife on my belt grinder and used a chainsaw file and fileguide to make the transition from ricasso to bevel even. Using the same file, I filed five small grooves into the spine of the blade to act as a thumb stop. I also drilled the holes for the handle pins and stamped my initials on the blade.

IMG_0320

2. After rough grind and heat treat

After rough grinding, I wrapped the blade in stainless steel foil, heated it in my heat treating oven, and hardened it using an interrupted oil quench. After the quench, I unwrapped the blade, tested for hardness, and tempered it twice in the oven at 425ºF.

After tempering, the knife was ready for the final grind. Using the belt grinder, I ground the entire knife to 400 grit, thinning the edge to its final dimensions. After grinding, I carefully hand sanded the blade, first with 280 grit sandpaper, and then with 400 grit sandpaper, to get out any wobbles in the machine finish and make the grit scratches run along the blade. I then taped the blade with masking tape to protect the 400 grit hand finish through the handle and guard fitting process.

IMG_0324

3. Knife after final grind and hand sand, wrapped with tape to protect the finish. Guard blank has been slotted.

To make the guard, I started with a 1 1/2” length of 416 stainless barstock, 3/4” by 3/8”. I cut a slot in the guard to admit the tang, using first an angle grinder with a cutoff wheel and then several flat files to fit the slot exactly to the tang.

IMG_0326

4. Cleaning up the faces of the guard blank on the belt grinder

IMG_0329

5. Drilling the pin hole in the blade

After fitting the guard blank to the blade, I drilled a hole through the guard, so that it could be pinned onto the blade. I then drilled through the blade using a carbide tipped drill bit to cut through the hardened steel.

IMG_0330

6. Shaping the guard on the grinder

With the pin holes drilled through both the guard and the blade, I shaped the guard on my belt grinder, and hand sanded it to 400 grit. Then I was ready to rivet the two together. I tapered the hole in the guard on both ends, using a homemade tapering tool, epoxied the handle and guard together to keep out moisture, and riveted the guard on, using 1/8” 416 stainless rod as my rivet stock.

IMG_0335

7. Handle material cut out

IMG_0336

8. Drilling pin holes in handle material

IMG_0333

9. Guard with holes tapered, next to the tapering tool

IMG_0334

10. Guard riveted with epoxy drying

Guard riveted and epoxied on to the blade

After attaching the guard, the knife was ready for its handle. I traced the full tang of the knife onto 1/4” thick micarta, and cut out two handle scales using a jigsaw. I then drilled through the handle scales and attached them to the tang using epoxy and 3/16” 416 stainless pins.

IMG_0337

11. Handle scales roughened with 50 grit paper

IMG_0338

12. Epoxy drying

IMG_0341

The finished knife, with handle shaped and finished

After the epoxy dried, I shaped the handle on my belt grinder, and finished it with 400 grit sandpaper.

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: