Category: Shop Science

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Poppies in the Fall

A project of remembrance

Poppies have played a role in my life since I was old enough to remember my first Remembrance Day ceremony in elementary school. Since then, those bright red, flocked plastic poppies have held a special place in my heart.

They are a fleeting thing. Seen first on November 1st on counters across the country. Worn proudly until the 11th hour of the 11th day on the 11th month when they are left on cenotaphs, memorials and gravestones throughout the British Commonwealth. I will always wear that little piece of plastic and buy one each year.

That said, I have often thought that something more tangible – beautiful even – and permanent would be a more appropriate marker for veterans.

This morning, the family got together at Valley View Cemetery for the moment of silence at 11am and to leave these tokens as our thanks.

I learned about the various colours of patina that copper was able to achieve with different chemical treatments. Blue, green, aqua and surprisingly enough, red! When heated coper is quenched in a solution of boric acid (Borax) and water, the coper is coated in a smooth dark red colour. Outstanding! The right colour, the right amount of permanence and some beauty thrown in for good measure!

Patterns are cut out of sheet copper and are textured with the narrow end of a light cross peen hammer. The texturing serves two purposes: to create a pattern more interesting and organic than flat sheet and to thin and define the edge of each petal.

Texturing of the pistil was accomplished with a round punch. this is purely to give some definition to the center. Following texturing, the pistil was rounded with a dapping block and punch to match.

From there, assembly! A little borax flux, a little silver solder and there you have it! Quenching the assembled poppy in the borax solution after each annealing built up the layers of colour. Some turned out much better than others, but with some repetition, I think they all turned out great! After I got the colour I was looking for, I scrubbed off any of the patina from the pistil and blackened the raw copper with a solution of liver of sulfur (potassium sulfide) and water.

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Isn’t Metal Already Hard?

The Cleaver: Part 2

Back in the shop and today was all about refining the shape, rough grinding and then the most nerve wracking process for a cutler; hardening!

Again, I am faced with the shadows of envy when I start writing a post. The envy being that my fellow artists here have the luxury of not only having a clean space for taking pictures (it is amazing how quickly the speakers on one’s phone collect metal dust and shavings in the shop), but that they can take pictures as things progress easily! In smithing one has about 15-30 seconds of workable heat (depending on the mass of material you are working with) once you take a piece out of a forge. Of that, only the 3/4 of that heat is useful for effectively forging out material. The rest is straightening and truing up material. Every heat takes time and also adds scale to the material and reduces the overall mass, so fewer heats is always best to maintain the cleanest end result.

But I digress. The end of all this wining and excuses is this: I will do what I can to get interesting ‘Work in Progress’ pictures, but there will be some inevitable gaps in process. Best thing is to get in touch and book a quick intro lesson to see it all for yourself (yes, yes…shameless plug. Totally ineffective given a global pandemic too!)

I try to forge as closely as possible to final shape given that I enjoy smithing and not so much grinding! Regardless, I am not proficient enough to eliminate the entire cleanup process with a grinder and above, you can see the layouts for the final blade shape. Further, the integral bolster was refined on the bottom roller of my Oregon Blade Maker 2″ x 72″ belt grinder. I lucked out that it was the right profile, but I think that the next thing on the ever evolving shopping list is going to be a set of small-diameter contact wheels. Getting into tight radius areas when shaping things like handle transitions and such is just so much nicer to do via power tools rather than files!

After rough shaping, it is all about the heat treatment. Heat treatment is the process where one takes the material to a specific temperature, then quenched in order to increase the hardness of the material. I’ll get into the specifics of all that in a later post (I find it fascinating, but I can imagine that it isn’t quite as interesting as glowing metal). First stage of heat treatment however is normalization: heating the material above the critical temperature, holding it there for a period of time, then cooling off in air. During heavy forging stresses develop within the crystal structure of the metal. This normalization process serves to normalize the entire structure and both reduce the likely of fractures and refines the grain structure (again, more on this later when I get into Shop Metallurgy).

So pretty isn’t it! After the normalization, more grinding! You can see that there was some additional material I needed to deal with at the tip to even out the thickness. Following normalization and any additional tweaks, it is time for the quench! Take a piece of hardenable steel (again, more on that later), bring it past the critical point and rapidly cool according to the material requirements. For most spring steel, this quench happens in warmed oil – I use canola – as it achieves the correct speed of cooling. Other steels will have different requirements and require either faster or slower quenches. Some steels also harden when cooled in still air (most stainless steels).

Know what you are using and apply the correct heat treatment process! This is one of the biggest dangers of Mystery Scrap Steels – you really don’t know what it is you are using. You can see if it is a mild, carbon or stainless steel, but the specifics are lost without a metallurgical analysis unavailable in a small shop.

And again, I digress…

After the quench, the material is exceptionally hard (if you did everything correct) and therefore brittle. To make this a useful tool, one needs to strike a balance between hard/brittle and soft/malleable. This process is tempering – bringing a material up to a significantly lower temperature to loose some of the hardness and bring in a level of malleability. For this material, a 400°F for two hours – repeated twice – brings down the hardness to a nice balance!

Yes, I used my kitchen oven. This process isn’t any different that seasoning a cast iron pan! I would like to draw your attention to the hammer marks on the blade for a moment. I always try to forge as clean and straight as possible, however the customer wanted a ‘brute du forge’ look for this blade to reduce material sticking to the blade when getting through large chunks of animal. As I had completely forgot about this and was exceptionally careful about forging as clean as possible, I then had to add back the marks. Ahh well, lets consider this a lesson in ‘Pay Attention to the Design Brief!’.

All in all, I think it is coming along very nicely! The next part will be all about finishing and adding a handle! To be honest, my least favorite part of the entire process…