Secret Santa 2017: a Bottle Opener

My colleagues and I, every year, take part in a Secret Santa gift exchange. I wanted to make an original piece, and I initially opted for a Naked Kiridashi (download the design here).


I prepared two printouts of the kiridashi and cut them to fit a 5mm thick C70 steel bar.


I glued the outlines to the steel bar with vinylic glue. It works well for the purpose, but it needs to be used generously. It dries quickly, and it keeps the paper in place for the rough cuts.


The first thing I like to do is drilling the holes. While the bar is still square, it’s easier to clamp on the drill press.


At this point, I realized a knife was not the ideal gift. I have to ship it overseas, and most probably it will travel with me in one of my next trips. To avoid problems and make it more gift-friendly, I converted the design to a handy bottle opener. It will be even more appreciated for sure.


I did all the rough cutting with the angle grinder. After taking this picture, I realized that gloves, earplugs, safety glasses, and respirator were not enough. I added a hat to the outfit.


This is the outcome of the rough cutting. It’s getting in shape, but it’s quite not there yet.


After a more refined shaping on the belt grinder, we are almost there.


Even without a cutting edge, I preferred to proceed with a heat treatment to harden the steel. This high carbon steel is pretty soft if not treated and it would wear out quickly otherwise. I heated up the piece with two propane burners and quenched it in water. I immediately checked that my file was skating on the hardened section. I gave it a quick manual sanding to remove the oxide that formed during the quenching and tempered it at 200 degrees Celsius for an hour in the kitchen oven. This is the yellow-ish shade it got after the temper.


I roughly sanded up to 800 grits, leaving quite some tool marks on the surface. I am looking for a rough finish, so I didn’t care much to get a mirror finish. I marked the year and the initials on the two faces of the bottle opener with nail polish.


After a 10 minute bath in a water solution of ferric chloride at 40%, the hardening line is more evident than ever. The harder steel oxidizes to a deep black, the softer part has a lighter shade after the etching.


After removing the nail polish with acetone, the etching reveals its beauty.


After a vigorous clean with warm water, dish soap, and abrasive dish cleaning sponge, the black oxidation is gone, and the etching looks very cool.

Here the final product. Now it’s ready to get into a beautiful box and shipped to its ultimate owner.


Making an Olive Wood Handle

Being the second knife I’ve ever made, I decided to play it easy and to focus on the handle. I purchased the blank blade and an olive wood chopping board.


I chopped down two pieces of olive wood, roughly of the same shape of the handle, plus some excess material.


I traced the outlines and drilled the pin holes on the drill press. I went for 4mm holes, enlarging the ones already present on the blade.


I prepared two brass pins and two pieces of G10 red liner.


I de-greased all the surfaces with acetone and glued all together with two-part epoxy.


Clamped them down and let it cure for 24 hours.


After the glue was cured I removed the clamps.


I had plenty of excess material, so I thinned it down with a metal saw. I went for a total width of 22mm: 4mm blade, 1 + 1 mm liner, 9 + 9 mm scales.


I taped the blade and started to get closer the final shape on the belt grinder.


I realized that the finish I had on the scale on the blade side it was wrong. I had to do it again, and it was not nice because I scratched the blade in a few points.


Got to a nice rounded shape and finished the sanding by hand.


Went up to 1000 grit on hand sanding but the tool marks on the tang were very hard to remove.


I finished the wood with beeswax. I let it dry and reapplied three times. Then polished.


And this is the final product.


Three things that went well:

  • Following the steps I watched on videos was super easy and effective.
  • Adding a red liner between the blade and the scales added a nice twist.
  • Beeswax made it a nice finishing on the wood.

Three things that did not go well:

  • I wasn’t able to remove all the tool marks from the tang.
  • There are scratches on the handle.
  • I scratched the blade while shaping the handle.

Three things I’ll do differently next time:

  • I glued way too excess wood on the blade so I had to re-do a few bevels on the scales. Next time I’ll refine the scales to a thinner width before glueing.
  • I will dedicate more attention to the final sanding of the tang.
  • I will sand more carefully the handle to avoid tool marks on the wood.