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!! clay brackets: weather/thermal shock advice needed

updated fri 10 oct 08


pdp1@EARTHLINK.NET on thu 9 oct 08

Hi Kelly,

If these are to be out-doors...then I would think to definitely do Fire to

Otherwise...without an image and size-info showing what this is as an
object...and what it's use is in better detail, the rest is too hard to
understand as for your other questions.

Sounds like fun though!

l v

----- Original Message -----
From: "Kelly Savino"

> OK, with all this talk of following your inner arteest, I got all
> inspired and took a new commission which is o so ethereal:
> I am making ceramic clamps to hold thermocouples to auto-sparking
> torches on a landfill, the kind made to burn off the methane gas emitted
> by the underground decomposition.
> I made a few prototypes and cut an extruder die in the shape of a cross
> section of the factory produced rubber piece I was given (uh, apparently
> those melt) and now that the initial R&D is out of the way, I can
> produce the required hundred or so.
> The first batch will be tested on site, over the coming months, and
> while I am ok with my clay body (a groggy classroom stoneware that
> claims to go from raku to ^10) I am debating with a friend over whether
> these should be glazed or unglazed.
> They should be relatively protected from thermal shock during use,
> though apparently in high wind the flames can lick down toward the
> bracket. They will be held in a metal clamp, and the long, thin, metal
> thermocouple that passes through the channel in the center of this
> two-piece ceramic doodad will be wrapped in a thin blanket of insulation
> (he'd been using fiberglass with little success, so I explained what
> kaowool is and where to get it.)
> So. Glazed, or unglazed? The goal is to withstand the winter weather,
> though he expects to have to replace the whole works every six months or
> so (thermocouple and all.) If these did crack, it wouldn't effect their
> utility, just the possibility of further use once disassembled.
> My current plan is to give him test samples of both sorts, and see what
> works best. It also occurred to me to try to fire a set below
> vitrification, though I imagine on second thought that porosity could
> lead to spalling.
> I'm wide open to suggestions, here... including (ahem) what to charge,
> for the set up, and then per item -- (on or off list works for me, since
> this might not be the kind of project of interest to most.).
> Now... let me adjust my beret and go commune with my muse...
> Yours
> Kelly in Ohio... canning plums, inventorying and defrosting freezers
> this week, stocking the pantry while the radio sings the wall street
> blues... trying to find inventive things to do with those remaining
> venison blade roasts before November brings better cuts again...