Niels Provos (Entries tagged as bladesmithing)

Heat treating the Wakizashi

nospam@example.com (Niels Provos) — Fri, 30 Jul 2010 20:33:16 -0700

Heat treating a sword using a water quench is a tense affair as the sword my crack and many hours of work may be lost. This video shows heat treating a wakizashi I made from forge welded cable that was folded several times. The Japanese differential heat treat calls for coating the back of the blade with a clay layer that retards the quench and allows the covered part of the steel to remain softer. The border between harder and softer steel becomes visible as hamon. Although, the heat treating was successful, the blade developed a welding flaw and at this point it looks like 20 hours of work might have been lost.

Folding Steel

nospam@example.com (Niels Provos) — Sun, 30 May 2010 19:26:51 -0700

When examining a traditionally forged Japanese sword, the steel structure (hada) often looks like wood grain. This structure is a result of folding and forge welding tamahagane. To simulate such hada without using expensive tamahagane, I took 24in of 1in diameter steel cable and forge welded it into a single piece of steel. That steel was then folded 7 times with some surface manipulation and then forged into a small wakizashi. The picture shows the tang after the scale was removed, polished and then lightly etched to show the grain. The steel structure seems similar to mokume hada. Now, I just need to find the time to shape, heat treat, polish and mount the sword. Expect progress pictures as work permits - probably in a few months.

Railroad Spike Knife

nospam@example.com (Niels Provos) — Tue, 23 Mar 2010 23:05:57 -0700

The is a knife made from a high carbon railroad spike. The blade is flat ground and about 4.5in long. The whole knife is a little bit longer than 10in. The twist in the handle feels nice in the hand. HC in this case apparently means 1030 which is pretty low carbon content for a knife. While it got to be very sharp, the edge is probably not going to stay that way for very long.

Forging this was a lot of fun and using the spring fuller really helped with separating the steel from the handle and the blade. Making this knife actually didn't take very long. About an hour of forging time, a couple hours of grinding and polishing.

Cable Tantos

nospam@example.com (Niels Provos) — Sun, 14 Feb 2010 19:16:18 -0800

Although, I have made various attempts at forging knives, this tanto is the first knife I have completed. It's a shinogi-zukuri tanto with choji hamon. The steel was made from forge-welded high carbon cable. Originally, this was supposed to become a wakizashi, but due to a bad hammer blow when forging the sunobe, I had to fold it over and no longer had enough steel for a longer blade. As a result, the blade is only about 9in long. The habaki was made from brazed copper and the shira-saya was carved from a popular blank.

The picture to the left shows two more cable tantos in various stages of progress. The top one had some rough grinding done to it whereas the bottom one is straight from the forge. Only about 10% of the time is actually spent forging the blades. The rest of time is spent grinding, polishing and working on the habaki as well as on the saya and everything else.

San Mai Knife

nospam@example.com (Niels Provos) — Thu, 15 Oct 2009 14:48:38 -0700

A while ago, I forged a San Mai billet with the hope to turn it into a tanto. Unfortunately, the forge I was using had a very oxygen rich atmosphere and the welds did not take very well. Over the last couple of days, I spent some time grinding and heat treating the remaining steel into a knife for practice purposes. The cable structure of the knife came out very nicely with repeated applications of lemon juice and metal polish to remove the oxides left by the lemon juice etch.

I also figured out how to take decent pictures of the steel. The trick was to use direct light rather than diffused light that shines directly on the blade, and then have black surfaces inside the light box. The angle of the knife needs to be so that the black is reflected do the camera. Although, this is a failed knife due to all the welding flaws, it still was an interesting experiment.

Forging a Wakizashi

nospam@example.com (Niels Provos) — Mon, 14 Sep 2009 11:43:26 -0700

I just finished taking the 5-day basic forging class taught by Michael Bell at Dragonfly Forge. The wakizashi in the picture is the result of it. The blade is about 18in long and was forged from forge-welded cable. The forge welding of the cable conducted by Michael and his son Gabriel took the better half of the first day. Afterward, the steel was forged into a sunobe which has the basic taper for the tang and point of the sword. We then forged in the ji and the shinogi ji. The remainder of the time was spent grinding in preparation for heat treatment. Before the clay was applied, we draw filed the blade so that all file marks were parallel with the edge rather than the perpendicular marks left by the belt grinder. Applying the clay was a three step process; a light coating of the whole blade, applying the ashi lines, and then coating everything that should remain soft. You can see the ashi and where the clay was applied on the middle picture. After heat treating, the blade took on a nice curve and it was back to the grinder. During the last day there was a little bit of time to polish on stones which showed hints of some very wild hamon as well as some mune yaki. The whole class was a great experience.

Building a forge

nospam@example.com (Niels Provos) — Mon, 22 Jun 2009 23:45:42 -0700

To get better control over the atmosphere in the forge, I have decided to build a blown gas forge based on a design by Tim Zowada. The basic structure is provided by a 10 gallon compressed air tank I picked up from Lowes. Using Tim's forced-air manifold, the forge should easily get up to welding temperature (2300F).

Jon who runs the TemperChi Glass Art Studio is helping with building this thing and already has some cerawool for lining the inside. The Cerawool is going to get covered with a 1/4in layer of Satanite and then with an ITC-100 coating. The forge floor will be made from Bubble Alumina refractory which has a heat rating of up 3300F and is supposed to be very resistant to flux. The inside diameter of the forge will be 8 inches and the length about 12 inches.

If you are interested in making glass beads, you can learn that at the shop, too, as well as welding

Hand forged Nessmuk knife

nospam@example.com (Niels Provos) — Mon, 29 Sep 2008 22:31:25 -0700

I just finished a three day bladesmithing class with Grant Marcoux in Alameda. He taught me how to make a Nessmuk knife out of O1 tool steel. The blade is hand forged. It has been normalized, oil hardened and tempered. The edge is so strong and sharp that it can cut even steel. The handle is made out of Padauk with a brass guard. Grant taught me how to make the knife step-by-step starting with the O1 round and forging it into rough shape. The class was fun and I have learned to really appreciate how much work goes into making a good knife. Now, I just need to convince my wife that it is okay to set up a forge at home.