ceramic triumph

[gfish]

I think I have found a good solution to the clay-adhesion problem: fiberglass reinforcement! I took a swatch of fiberglass left over from rocketry projects (12oz, if I remember correctly), cut it into 1cm squares, then teased out the individual fibers and mixed them into some fairly wet clay. Even just spreading a test section onto the blade made it obvious how much better this was. It spread like creamy peanut-butter, instead of the lumpy porridge I had got before. I let it dry overnight, and no cracks! So I held a propane torch on it until the clay was starting to glow. Still no cracks! We'll see how the heat-treating goes later in the week, but I have very high hopes for this combination. I'll have to swing by Fiberlay to get a container of precut fiber additives. Doing it by hand is slooooow.

Comments

[basal-surge.livejournal.com]

I use finely chopped straw or just go the medieval method and mix in some animal dung (precut!) with the clay. This is mostly for crucibles, mind, not tempering clag, but the principle is the same.

[gfish.livejournal.com]

Straw was actually what I first thought of, but I didn't have any on hand.

[randomdreams.livejournal.com]

Interesting fact! to me at least! is that old plaster-and-lath walls were reinforced with pig bristles!

(I've never seen a bristly pig, though, so I'm kind of suspicious. Maybe they just shaved?)

[randomdreams.livejournal.com]

Do you make your own crucibles? How tough are they? Could they stand 800 C and hold, say, 10 kilos of aluminum? I've had porosity problems with castings and I'm told it's from my crappy homemade steel crucibles.

[neuro42.livejournal.com]

I have a tub of 1/32" milled glass for that very purpose (s/clay/expoxy) somewhere if you want it.

[basal-surge.livejournal.com]

Probably not - strictly small volume, base metals - pewters and bronzes, mix of clay/dung/quartz sand, based on viking age casting crucibles for doing bronze jewellery work - I'm an experimental archeology freak. They'll stand more than 800 centigrade, more than once, but I'm not sure they would translate well to that volume of metal and weight.

Have you tried lining your steel crucible with a refractory and flux surfaced ceramic of some sort?

[gfish.livejournal.com]

I got this book (http://www.lindsaybks.com/dgjp/djgbk/cruc/index.html) for corivax. It looked quite good when I paged through it, but we haven't tried making one yet.

[gfish.livejournal.com]

I'd like to get a bit at least to see if that's too short. Hopefully not -- fibers as long as the ones I'm using make it really hard to do some of the fine detail work needed to define the hamon in a traditional style. Doesn't matter for the machete, but eventually I'll want the capability.

[neuro42.livejournal.com]

I'll try and find it, I haven't seen it since I moved.

[randomdreams.livejournal.com]

I haven't. That's my backup plan.

[randomdreams.livejournal.com]

I've seen that book! I'd love to look at it some time when I'm out there. (in fact, didn't we discuss this once before, about two years ago? I can't ever remember)