Jeroen Zuiderwijk

Doesn't that just give two boiling temperatures? First of the oil boiling until the oil is boiled off, then the wax?

Yes, but with the gap filled with the cutler's resin. If done well, there is virtually no gap. But since I was still learning to burn into the horn, there's a bit of gap that will be filled. If I'd burned it in a little deeper, and cut off the first part of the hilt, it would have been a very tight fit.

Got some time today to (re)do the hilt for the Osmund knife. The horn hilt burned in earlier was not usuable, as it had a nasty delamination that went from the back end to halfway into the hilt. Fortunately I had another nice piece of cow horn, just about the right dimensions that I could get a hilt out of it. I burned in the hole again, and shaped it by axe, rasp, file and then finished by sanding. I still need to buff it to make it shiny. The new hilt has a nicer coloring, so I'm quite happy with it. Work is starting again tomorrow, so progress is going to be at snail pace again.

That's the case for later broken back style seaxes. Earlier ones usually had only part of the hilt covered.

Today I had to make a rivet heading tool, and since I had the forge set up I also started on a new project. A very small blade (about 8cm), but with lots of new challenges. It's intended to be a reproduction of the Osmund knife: https://collections.museumoflondon.org.uk/online/object/29492.html The blade is composed of wrought and a piece of layered W2 for the edge, the last bit of edge billet I had left from the seax forging course at Owen's. I'd already forge welded these together earlier, and today I forged the blade to shape. And since it's a small blade, I could do the forging and have it filed within a few hours. And I also started on the horn hilt. I pre-drilled the hole, then burned in the tang. Works just as well on horn as on wood apparently, but a lot smellier! And it took quite a few more burns. Mostly the horn just melts rather then burns, and a hot goo of molten horn bubbles out of the hole as you burn in the tang. Obviously the hilt will be trimmed down a lot to the final shape. Other fun new challenge with this one will be the inlays and niello. I've already made niello earlier, so that's one step of the process done.

I've applied the decoration based on one of the Groningen sheath finds (Usquert). Quality is a bit meh due to f.e. the waviness of the lines. Next time lines first, then stitching holes, stitch and then glue the flaps together. I also had to do a bit of guess work on the snake patterns. And since had a longer panel left near the tip, I had to be a bit creative with how to fill it in. It's alright as a practice piece I guess. And since I rarely actually get around to make sheaths or scabbards as this is generally the plan, but never done, I'm happy I got this far. Now I need to seal it. I'm questioning whether to use grease or wax. Wax would be better, keeping the leather more stiff. But I did a practice piece, and it got so dark that it hid the patters almost entirely. Of course I can fill the patterns in like the The St Cuthbert Gospel, but hmm... And I need to apply rivets and suspension. And for that I need to make rivets, and for that I need to make rivet heading tools.

I used a flat tipped needle. I simply converted a normal one, by annealing it and hammering the tip flat. Next time I will harden it again though, as I had to keep straightening it out

Yep, absolutely. It's also known as welding shivers. And with lead, there is no safe threshold it is safe. Even the smallest amounts of lead can provide severe health issues.

On the original sheath(s) it's just one hole or slit on the surface, rather then two. And the row on the other side is staggered with regards to the first side. You don't need the second holes if you do 45 degree angles, you can use the same hole to go back. I did end up using two holes occasionally, but that's simply because the needle exited next to the pre punched slits.

This is the type of stitch:

Basically like this. If you stretch the metal in the directions shown by peening (larger arrows more peening), then this should pull the edge that is now stretched too long back straight again.

Yesterday I started on stitching the sheath. I'm using a zigzag stitch, which was also used on the Groningen sheath(s). I yet have to figure out how to do this correctly. At least the way I'm doing it is certainly not the way to go. I punched the holes on the front side only, and started stitching the thread at about 45 degrees, and then back through the same hole at 45 degrees to the other side. At least that's the intention. But getting the needle to exit exactly where I want is a real challenge. On the back side, it's a total mess, certainly the first 10 stitches, which are between 2cm and 2mm apart. But like everything I make, I consider this a practice piece to learn from. Mistakes are part of the process. On the front side, I just keep poking the needle until it exits the pre-punched holes (or right next to it). There has to be an easier way to do this. Next time I will punch the holes on both flaps at 45 degrees and stitch before gluing the flaps. At least then any mismatch will be hidden on the inside. Anyway, it's an interesting stitching pattern, that I haven't seen anyone else doing. Does anyone else have experience with it?

It may seem counter intuitive, but you can take out a warp like this by hammering the metal behind it. If that stretches out, it will pull the edge straight. But you have to do it right. If you do it wrong, then you just create more warping

P.s. this is what you see when zinc is boiling when casting brass: white/yellow flame in the crucible, and smoke coming out of the crucible. If that happens outside, and you stay out of the smoke, and you don't have any lung issues, you are probably fine. But personally I rather stay away from zinc all together. No point in risking it, and I hate brass anyway.

Metal fume fever only happens due to fumes when casting. So you won't get it from dust. And it's mostly zinc oxide that causes metal fume fever. Zinc has a low boiling point, so when melting brass, the zinc can start to boil off, creating lots of zinc oxide fumes (white smoke) that can cause zinc fume fever. Other metals can cause it too, but not copper or tin. Which is why I almost always use pure copper and tin for casting, as it's relatively safe. Symptoms of metal fume fever include: "fever, chills, nausea, headache, fatigue, muscle aches, joint pains, lack of appetite, shortness of breath, pneumonia, chest pain, change in blood pressure, dizziness, and coughing. A sweet or metallic taste in the mouth may also be reported, along with a dry or irritated throat which may lead to hoarseness". So just fever and no other symptoms don't mean that it's more likely metal fume fever. So IMO your fever is not related to the bronze working that you did. So it's either just a fever, or something else unrelated to the bronze itself. Carbon monoxide jumps to mind, but you'd experience that more in terms of dizziness and headache and not fever.

I'm eager to find out what was used to fill in the grooves. I've seen resin being used in a sword blade IIRC, and also inlayed gold and copper. I'm very curious what was used in this case.

Yeah, and get it to a high enough temperature. Normally I fire lost wax moulds at at least 800C for a few hours. This ensures that there is also no carbon residue remaining from the wax in the mould material.

Melting it out isn't sufficient. The mould will soak up the wax. This needs to be properly burned out. If there is splutter and flames coming out of the mould, there is still wax soaked into the mould. That will burn and the resulting gasses will push the metal away, creating voids in the casting.

Still need to do the final polishing, but the blade is looking better and better. I'm going to cast the scabbard mouthpiece and slide some time in the future. I'll have to start making models/moulds for those. The mouthpiece will be a tricky cast, as they seem to be of very thin metal. I may do it in a soapstone mould, by which I can make the thinnest casts from my experience.

Yesterday I spend an evening untangling a skein of silk yarn (about 100 meter), which I had turned into big knot because I'm a nincompoop who doesn't understand how to unwind a skein properly. I've untangled about 90% of it. It's madder dyed silk, to wrap the grip in of my Han Dynasty dao. I still need to braid it without entangling it again, which will also be a challenge

For great memories like that you are welcome too. It is related though, since I did the seax lecture then, and I believe I brought this seax with me in unfinished state. So it's still on topic

One of my favorite photos and moments too. It was great to be among such talented and inspiring people, particularly for an amateur like me I hope there will be more times like that!

Yeah, I love that video, and the one previous to it. I love that difference in mindset. We try to perfect our craft all the time. I usually have the mindset to make somthing as good as I can. Good enough doesn't exist, but it's as good as I can make it now, and I'll do better on the next. But in cases like this it's refreshing to try to let loose of that, and do a fast low quality finish like on the original.

First, was the plaster sufficiently burned out? If not, you'd have probably noticed the metal bubbling or spitting in the mould. Secondly, brass is very fickle to melt and cast. If underheated, it's too thick and gloopy to cast. If overheated, it turns into a thick gummy mass. I hate casting it for that reason (and the toxic zonc smoke if it overheats).

I think he didn't care, and the decoration on the back was placed with as little effort as possible. The front side looks neatly done though.