Damascus Steel Kitchen Knives Part 1-3

Forging the steel - Day 1

For my 60th birthday, my wife Louise bought me a course at the Tharwa Valley Forge in Canberra for a 3 day Damascus kitchen knife making course to make 2 knives. This is a description of the process.

Our Damascus steel was made by using alternating layers of 1075 and 15N20 steel with 9 layers, with the thicker 1075 on the outside. The steel blanks are ground to a clean and shiny surface using the belt grinders before being cleaned with acetone, stacked and welded together to make our first billet.

The billets are then dipped in kerosene which provides a flux that removes oxygen between the layers of steel as it enters the forge. The billet is heated in the forge until it reaches critical temperature at about 1250 centigrade with a bright yellow white colour.

When the steel has reached temperature, it is placed lengthways in the press to squash the billet evenly at 1500 PSI to weld the billet together. This process is done 3 times before proceeding to drawing out the billet.

Drawing the billet is achieved by heating the billet and using the press to depress the billet every 5cm along the billet, reducing the height and spacing the billet. This is done another 2 times before turning the billet on its side and pressing the side and top and bottom, drawing the billet out to a long square shape approx 500 mm long.

Once this is done, and the drawn out billet has cooled, it can be ground using a hand  grinder taking the surface back to bare steel on both sides. The billet is then cut in 3 even pieces using a drop grinder.

The three pieces are then put to the belt sanders again to remove contaminants and cleaned with acetone again before being welded again.

The process repeats again, dipping the new billet in kerosene and into the forge, heating, welding the billet 3 times before drawing the billet out again, then grinding and cutting the billet into 3 more pieces.

The process repeats a third time before drawing the billet out again. This time the billet is drawn flatter and wider to accommodate the proposed knife shape using the power hammer, roller and other tools.

The result is a Damascus steel billet of 243 layers.

Ric Noble

19 April 2024

https://youtu.be/DGatFK3pxeQ?si=4Ge0lNTKsqKmnvVT

Tharwa Valley Forge

https://www.tharwavalleyforge.com/

Damascus Steel Kitchen Knives Part 2-3

 Shaping the Knife -  Day 2

Shaping a knife generally starts with shaping the tang of the knife. The tang is the narrow part of a knife that fits into the handle. We used a smaller forge for this process and only heated the area of our billet that we needed to manipulate. 

Fortunately we had an induction forge to provide instant heat which uses electricity through looped steel tubing to heat our billets quickly.

Shaping occurs using the forge and hammer, drawing out the tang first, which is the narrow section of the knife for the handle. The billet needs constant manipulation, developing the ricasso or heel of the knife and then drawing out the blade itself. This is achieved by constant heating and manipulating, although there is usually about 8 or so minutes between adjustments.

Once the tang, ricasso and blade shape is confirmed, the knife can be cut to size, noting a  centimetre short given the blade will be drawn out further again later.

At this time, we repeated this process as we were making a second knife.

We ended up with 2 knife blank shapes. We then took these knives to the belt sander to shape our knives to a true shape and sand back to a shiny steel finish.

We now had our true knife shape and took them back into the forge to 1200c and then quenched in canola oil for the heat treatment.

After quenching, the knives are baked in an oven for 2 hours to temper the steel. After baking, the knives are sanded back to bare steel on the belt sanders and a step cut into the tang in order to fit the handle.

Ric Noble

20 April 2024

https://youtu.be/RTBK9Uf9KJY?si=JAD0w1sOMr9gnNvl

Tharwa Valley Forge

https://www.tharwavalleyforge.com/

Damascus Steel Kitchen Knives Part 3-3

 Finishing the Knife -  Day 3

Day three starts with a heavy sanding task in order to sand lengthways on the blade in order to sand out the band sanding marks left by the belt sander along the short profile of the knife. This sanding task is done by hand sanding with 120 grade sandpaper, moving to 180 and finishing off with 320 grade resulting in a clear metallic surface with no obvious scratch marks in either direction.

Etching

The next step is etching which brings out the unique pattern effect of the damascus steel. Once the blade is cleaned and free of any impurities such as fingerprints and grinding dust, the blade is lowered into a mild acid solution and allowed to cure for five minute periods, removing and gently wiped with steel wool between immersions. Even after the first immersion the amazing damascus pattern is evident.

After three acid immersions, the blade is run under cold water for about 3 minutes and sprayed with a substance to neutralise the etching process. Once dried, the blade is lightly coated in wax.

Handel construction

Our kitchen knives had a handle length of 120mm with a bolster (the part of the handle closest to the blade) being 25mm and the handle being 95mm. We were provided with a choice of wood and some spacers to go between the bolster and handle  to add a stylized break between the two. I chose two different pieces of wood, rosewood and teak. The wood is cut to the approximate dimensions mentioned above although larger before the handles are tapered down. I chose to interpose the bolsters of my knives so I had a light bolster and dark handle on one knife and vice versa on the other.

Once the handles and bolsters are cut, the handles are drilled to the length of the tang and the bolters are precision cut to allow for the stepped-in cut in the tang. The spacers are punched to allow them to be threaded onto the tang. My spacers included a brass plate with a black spacer on either side creating a stylised emphasis on the brass.

Once all the handle pieces are able to fit comfortably, the handle is glued in place. A two part epoxy glue is used and the handle held in place for 5 minutes while the glue sets. Any excess glue can be removed from the ricasso and tang before the glue sets hard. The knives are set aside to set hard over a longer lunch.

Once all glue is set, the handles are put to the belt grinders again to square the handle. A centre line is drawn on the handle in line with the knife's tang in order to grind the sides of the handle evenly and then rotated 90 degrees in order to evenly grind the side of the handle.

Once the square handle is formed, the four corners are ground back to make an octagon shaped handle and shaped base of the handle. Additionally, hand sanding ensures a final 320 grade sand of the handle before oiling.

The final finish is a blade sharpen and polish. Additionally we were able to add a laser message on to the blade as a name word or short message. I am so happy with my two knives I left the forge with. While I had assistance from the course instructors, I truly feel I have created these knives and have had a meaningful learning experience.

Ric Noble

21 April 2024

https://youtu.be/RTBK9Uf9KJY?si=JAD0w1sOMr9gnNvl

Tharwa Valley Forge

https://www.tharwavalleyforge.com/