Apprenticeship Session 4

Since the forge is set up for wreath-making season, we chose to work on fire strikers rather than continue our bellows project. So we started with the pieces we had hammered out the last time and started to draw out one end to a taper. I guess it’s not a true taper since with a fire striker you want to keep one edge straight.

One side tapered

As we continued to work, our instructor (have I mentioned that his name is Doug Swenson of Goose Prairie Forge?) took a moment to explain the hardening process and a few tricks that can help get the steel as tough as possible. Fire strikers need to be really hard in order to spark. So the first thing he recommended to do once the item is forged into shape is to hammer on it to compress and align the metal structure. It’s not a hard hammering but it’s a bit more than a tap. So he did a demonstration for us where he took a bit of steel and forged it for a bit, quenched it in water, and then broke it to show us the grain structure. Then he did pretty much the same thing but this time he packed it down with the hammering first. It’s a noticeable difference in the grain structure with the second one being a much finer grain. He also pointed out that steel that hardened well during the quench will have a mottled appearance you can look for.

After that demonstration we continued working on our fire strikers (we were there nearly 5-1/2 hours) and Rob managed to complete his including hardening and grinding.

I however did not quite finish and therefore had some homework to do. I had my fire striker pretty well forged into shape, but it needed just a bit of clean up and then hardening. So I fired up our home forge and cleaned it up by hammering out a few kinks. Then I put it through the normalization process where you heat the piece up to critical temperature where it becomes non-magnetic and then just let it air cool until you can touch it. It goes through normalization (aka thermocyclingthermocycling Thermocycling is the process of heating steel to critical temp (non-magnetic) and then letting it air cool. Usually done three times in a row.) three times before the final heat for the quench. It came out nice and mottled so it looks like the hardening went well. The last step for the fire striker is to grind the striking edge as the metal needs to be shiny to get sparks. So a short spell on the belt grinder being careful to not heat up the metal which would ruin the hardening (I dipped it in water after every pass on the grinder). In under an hour I had a finished fire striker that even produced some sparks!

Apprenticeship Session 2

So we started to build our Viking-age bellows tonight. Doug had the wood pieces all pre-cut and ready to assemble, which makes it sound quick and easy. However, three hours later we have one bellows only half assembled. There’s more to it than you’d think.

Making the Valve

Our previous session went over how the valves work and what they should look like. (Refresher: two pieces of leather – one square, one rectangular – placed over the air intake hole in the wood.) So today it was time to cut the leather and install it inside the bellows.

Making the Hinge

The next step is to make the hinge. This too is made of leather. We started by putting spacers in between the top and bottom pieces of the bellows so that they were flush with the wooden snout piece.

bellows wood pieces set in place
Bellows wood pieces set in place

After that it was time to cut the piece of leather that was going to serve as the hinge. We needed to determine the size we would need to cut. We wanted it to cover the wooden snout piece and then a couple of inches of the bellows surface (I’m sure that has a name, but I don’t know what it is). Plus it needs to fold over the sides too.

To be clear, the leather used for the hinge was a reasonably thick piece of leather since it’s going to get some hard work and different than the leather used for the valve as that should be more flexible.

After the leather was cut, we drilled a couple of hole through the top piece of the bellows as we planned on riveting the leather to that piece. The placement of those holes was about an inch or so from the front and sides.

We used an awl to punch holes through the leather hinge before heading to the anvil to rivet it in place.

Once the main rivets were in place it was a matter of adding tacks and small nails to secure the leather to the snout and the board and make the hinge as strong and tight as possible. We also added glue to make it secure.

At the end of our session we had gotten that far on just one of the bellows. Going to have to finish them up next time!

Apprenticeship Session 1

So we started our apprenticeship with Doug Swenson as part of the Folk and Traditional Arts Apprenticeship grant that we received. The work plan was originally developed about six months ago and we’ve learned a lot since then. And we are about to leave on a trip and be away from the forge for several weeks so we kind of are starting out of order with the Viking-age bellows.

We’ve used Viking-age bellows once or twice and they are surprisingly easy and fun to use. There’s actually not a lot of information about them because they haven’t survived through time very well and they aren’t mentioned to often in literature or historical accounts. There is a cool depiction of one on a runestone from Sweden.

ramsund runestone carving
The Ramsund Carving Sö 101 with Sigurd the Dragonslayer, note the bellows at lower left. Credit to Jonas Lau Markussen.

We spent a bit of time going over how bellows evolved and how they work. Some have a single chamber and others have a double chamber. Later ones got rather large and hung overhead, operated by a lever or a foot pedal. But they all essentially work the same way: air goes in one end and is directed out as smoothly and steadily as possible out the other end. And valves in the middle keep the air moving in one direction.

So we started talking about the valves for the bellows we are about to build. In this case we are going to use leather for our valves. It’s a traditional material and actually quite suited to this purpose. The air intake is actually just a round hole cut into one side of the bellows and the valve consists of a couple of pieces of leather that cover that hole. However, there’s a bit of elegant math to the size and placement of the leather pieces. There’s two pieces that are involved. The first is a square large enough to cover the hole plus a bit more. That piece is placed with corners to the front and back of the bellows and tacked down at the sides. The second piece of leather is twice the length of the first piece and covers it and is tacked down at the corners. It should be extremely taut as it will need to allow air to pass through it freely.

bellows design notes

After that we looked at the construction of the bellows that our master blacksmith instructor uses in his Viking-age demonstrations. Most of it is very suited to purpose and have stood up to use and time, but we might make a few minor adjustments when we build ours.

Inaugural Cloak Pin

We’ve been wanting to try making a cloak pin for awhile now and gave it a go for the first time today. Room for improvement, but not bad as a first attempt!

Fire Striker – Drawn Out

Been learning to make fire strikers. This one’s from soft steel so probably no good for lighting fires, but great for practicing on! It started as a 4″ piece of bar stock and it’s now drawn out to 7.25″. Next up – the curls!

I don’t know that I’ve shared this yet, but this is the Viking Age knife I made at the Fiber and Flame event in late June 2019. It is my second knife. Started with a chunk of coil spring from a car. The handle is made of ash from a tree growing near Hedeby. This one is not for sale. Ever. Than you Jeppe Nordmann Garly for sharing your expertise all the way from Norway!

Kicking off the Fiber & Flame event with pizza – traditional Viking food, right?