[Clayart] Why you don't tell a Norwegian a joke on Thursday*. Mold release, crash cooling.

[Vince Pitelka]

Hi Duff -
In my experience Mizzou castable does not shrink at all, not even slightly.  For a quality castable refractory, it would pretty much defeat the whole purpose if it shrunk in drying or firing, wouldn't you say?
- Vince

Vince Pitelka
Appalachian Center for Craft
Tennessee Tech University
vpitelka at dtccom.net  
sites.tntech.edu/wpitelka/

-----Original Message-----
From: Clayart [mailto:clayart-bounces at lists.clayartworld.com] On Behalf Of Douglas Fur
Sent: Saturday, May 12, 2018 11:32 AM
To: Clayart international pottery discussion forum <clayart at lists.clayartworld.com>
Subject: [Clayart] Why you don't tell a Norwegian a joke on Thursday*. Mold release, crash cooling.

One thing to consider when using castable  refractories is they shrink, slightly. This will put a squeeze on any inside form. For small holes a few layers of newsprint topped with plastic wrap around an inner core gives
enough cushion that  the core can be slid out. For larger or   complex
shapes a core needs to be made so that it can be disassembled and taken out.
""Concrete cracks at corners" is a truism to remember a radiused inside corner is preffered to a sharp angle.
A folk tale at the University of Oregon reported that David Stannard was seen loading an Alpine kiln at midnight. He and his fired pots were gone when folks came back in the morning. Moderation in the ammount of gas used so that the heat produced stayed in the kiln and crash cooling with the blowers on were given as how he dun it.

Duff
Seola Creek


*"because he'll laugh during the sermon."
(or post comments after the topic is long gone)
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.clayartworld.com/pipermail/clayart/attachments/20180512/b43e640f/attachment.html>